Item No.
TO: HONORABLE MAYOR AND MEMBERS OF THE CITY COUNCIL
FROM: OFFICE OF THE CITY MANAGER
BY: MATTHEW BAUMGARDNER, P.E., DIRECTOR OF PUBLIC WORKS/CITY
ENGINEER
DATE: AUGUST 8, 2023
SUBJECT: RESOLUTION ADOPTING THE CITY’S SEWER SYSTEM MANAGEMENT PLAN
APPROVED BY
CITY MANAGER
EXECUTIVE SUMMARY
The City Council will consider adopting a Resolution approving the City’s Sewer System Management Plan (SSMP). State Water Resources Control Board (SWRCB) Order No. 2022- 0103-DWQ Statewide Waste Discharge Requirements General Order for Sanitary Sewer Systems (General Order) became effective on June 5, 2023 and requires sanitary sewer systems, such as the City’s, serving a population of more than 100,000 to update their SSMP to comply with the latest General Order. The City’s SSMP provides a plan to manage, operate, and maintain the City’s sanitary sewer system and to help reduce and prevent emergency spills, as well as mitigate any sewage spills that may occur.
RECOMMENDATION
That the City Council:
Adopt Resolution No. 23-8187, a Resolution of the City Council of the City of Downey approving the City’s Sewer System Management Plan.
BACKGROUND
On May 2, 2006, the SWRCB adopted Order No. 2006-0003 (Sanitary Sewer Order), a General Waste Discharge Requirement (WDR) for all publicly owned sanitary sewer collection systems in California with more than one mile of sanitary sewer pipe. As the City’s sewer collection system is comprised of approximately 200 miles of sewer mains, the City submitted an application or Notice of Intent (NOI) for coverage under the Sanitary Sewer Order to the SWRCB.
The goal of the Sanitary Sewer Order was to provide a consistent Statewide approach for reducing Sanitary Sewer Overflows (SSOs). To help achieve this goal, the Sanitary Sewer Order required public agencies that own or operate sanitary sewer systems to develop and implement SSMPs and report all SSOs to the SWRCB’s onli ne SSO database. The City therefore prepared and certified its SSMP and constituent subparts/elements were in compliance with the Sanitary Sewer Order following adoption of the SSMP on January 12, 2010.
SEWER SYSTEM MANAGEMENT PLAN
AUGUST 8, 2023
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2 On December 6, 2022, the SWRCB adopted the General Order to replace the original Sanitary Sewer Order. Sanitary sewer systems, such as the City’s, were subsequently asked to certify continuation of regulatory coverage from the Sanitary Sewer Order to the General Order, which staff has completed. On June 5, 2023, the General Order became effective, and the original Sanitary Sewer Order was rescinded.
Although similar to the SSMP required under the Sanitary Sewer Order, the General Order amended the categories of SSOs and reporting requirements , necessitating an update to the Spill Emergency Response Plan amongst other SSMP modifications. The City therefore enlisted the services of on-call consultant, Tetra Tech, Inc., to update the City’s SSMP (Exhibit A - Attached) in compliance with the latest General Order.
ANALYSIS
The format of the SSMP follows the numbering and nomenclature specified in the General Order and includes the following eleven sections:
1. SSMP Goal and Introduction
o The goal of the SSMP is to provide a plan and schedule to properly manage, operate, and maintain all parts of the City’s sanitary sewer system. This will help reduce and prevent emergency spills, as well as mitigate any sewage spills that may occur. The plan complies with the SWRCB Order WQ 2022 -0103-DWQ and will be periodically updated in accordance with the requirements of the order.
2. Organization
o The intent of this section of the SSMP is to identify City staff responsible and chain of command for implementing the SSMP, responding to sewer spill events, and meeting the spill emergency reporting requirements. This section also includes the designation of the authorized representative to meet SWRCB requirements for completing and certifying spill reports.
3. Legal Authority
o This section of the SSMP discusses the City’s legal authority to comply with the SSMP requirements as provided in its Municipal Code and agreements as they relate to prevention of illicit discharges, proper design and construction of sewers and connections, sewer lateral maintenance, enforcement measures, agreement with the Los Angeles County Sanitation Districts (LACSD) for the collection and treatment of the wastewater produced in the City, and control of inflow and infiltration from satellite sewer collection systems.
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AUGUST 8, 2023
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3 4. Operation and Maintenance Program
o This section of the SSMP presents the City’s sanitary sewer collection system operations and maintenance (O&M) program including: collection system mapping including updates to existing drawings and incorporation of new improvement plan drawings, preventive O&M activities, rehabilitation and replacement plan, training program for staff, equipment and parts inventory, and standard operating procedures for sewer cleaning.
5. Design and Performance Provisions
o This section of the SSMP discusses the City’s design criteria and standards and specifications for the construction, installation, repair, and rehabilitation of existing and proposed sewer system infrastructure components, including but not limited to pipelines, lift stations, and other system appurtenances as well as the procedures and standards for inspecting and testing the installation of such improvements.
6. Spill Emergency Response Plan (SERP)
o The purpose of the SERP is to provide an orderly and effective response to SSOs and sewer spills. This plan provides guidelines for City personnel to follow in responding to, cleaning up, and reporting spills that may occur within the City’s service area. This section also discusses the City’s standard operating procedure for implementation of the plan.
7. Sewer Pipe Blockage Control Program
o This section of the SSMP presents the extent and nature of sewer spills related to Fats, Oils, and Grease (FOG) and discusses the Sewer Pipe Blockage Control Program including: nature and extent of FOG problem, public outreach program, and sewer pipe blockage control program activities.
8. System Evaluation, Capacity Assurance and Capital Improvements
o This section of the SSMP discusses the City’s System Evaluation, Capacity Assurance and Capital Improvements Plan (SECAP) which evaluates the hydraulic capacity of the sewer system and identifies hydraulic deficiencies, if any, that contribute or may contribute in the future to sa nitary sewer overflows, and develops a capacity assurance plan to address identified deficiencies, if any, including short- and long-term capital improvement projects.
4 SEWER SYSTEM MANAGEMENT PLAN
AUGUST 8, 2023
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9.Monitoring, Measurement, and Program Modifications
o This section of the SSMP presents the City’s approach to monitoring, measurement, and program modifications including: sanitary sewer operating performance measures and tracking of SSO frequency, historical performance data, baseline performance from the implementation of the original SSMP, and performance monitoring and program changes.
10. Internal Audits
o This section of the SSMP discusses the process the City will follow to audit its SSMP and related programs in accordance with the requirements and frequency required in the General Order.
11. Communication Program
o This section of the SSMP discusses the process involved in communicating with sanitary sewer customers and interested members of the public regarding the development, implementation, and performance of this plan.
The City’s SSMP was prepared in accordance with the latest General Order and with the intent to provide a plan to properly manage, operate, and maintain all parts of the City’s sanitary sewer system and to help reduce and prevent emergency spills, as well as mitigate any sewage spills that do occur. The attached resolution (Attachment A) has been prepared for Council’s consideration to adopt the City’s latest SSMP in accordance with the requirements of the General Order.
CITY COUNCIL PRIORITIES
Efficiency & Adaptability
Quality of Life, Safety and Infrastructure
FISCAL IMPACT
There is no fiscal impact.
ATTACHMENTS
Attachment A – Resolution No. 23-8187, approving the City’s Sewer System Management Plan
Exhibit “A” to Resolution No. 23-8187, Sewer System Management Plan
RESOLUTION NO. 23-
A RESOLUTION OF THE CITY COUNCIL OF THE CITY OF DOWNEY
APPROVING THE CITY’S SEWER SYSTEM MANAGEMENT PLAN
(SSMP)
WHEREAS, on May 2, 2006, the State Water Resources Control Board (SWRCB) Order No. 2006-003 (Sanitary Sewer Order) Statewide General Waste Discharge Requirements (WDR) for Sanitary Sewer Systems was adopted and implemented; and
WHEREAS, the purpose of the Sanitary Sewer Order was to develop a regulatory mechanism to provide a consistent statewide approach for reducing sanitary sewer overflows (SSOs); and
WHEREAS, the Sanitary Sewer Order required public agencies that own or operate sanitary sewer systems comprised of more than one mile of pipes or sewer lines which convey wastewater to a publicly owned treatment facility to apply for coverage under the Sanitary Sewer Order, develop and implement SSMPs, and report all SSOs to the SWRCB’s online SSO database; and
WHEREAS, the City of Downey’s (City’s) sewer collection system is comprised of approximately 200 miles of sewer mains; and
WHEREAS, the City filed a Notice of Intent (NOI) for coverage under the Sanitary Sewer Order with the SWRCB and certified that its SSMP and constituent subparts/elements were in compliance with the Sanitary Sewer Order within the timelines established for each; and
WHEREAS, on December 6, 2022, the SWRCB adopted Order No. 2022-0103-DWQ Statewide Waste Discharge Requirements General Order for Sanitary Sewer Systems (General Order); and
WHEREAS, the General Order serves as the new statewide waste discharge requirements regulating sanitary sewer systems; and
WHEREAS, prior to June 5, 2023, the City was asked by the SWRCB to certify continuation of regulatory coverage for the City’s sanitary sewer system from the Sanitary Sewer Order to the General Order which was subsequently completed; and
WHEREAS, on June 5, 2023 the General Order became effective and the original Sanitary Sewer Order was rescinded; and
WHEREAS, the new General Order requires development of an SSMP to provide a plan to properly manage, operate, and maintain all parts of the City’s sanitary sewer system and to help reduce and prevent emergency spills, as well as mitigate any sewage spills that do occur; and
WHEREAS, the SSMP has been prepared in compliance with the General Order and will be periodically updated in accordance with the requirements of such order; and
NOW, THEREFORE, THE CITY COUNCIL OF THE CITY OF DOWNEY DOES HEREBY RESOLVE AS FOLLOWS:
SECTION 1. The above recitals are all true and correct.
RESOLUTION NO. 23-
PAGE 2
SECTION 2. The City Council of the City of Downey does hereby approve the attached SSMP (Exhibit A).
SECTION 3. The Director of Public Works, or his designee, is hereby authorized to certify via the SWRCB’s online database that the SSMP is complete and in compliance with the General Order and to certify any ongoing compliance reports as required by the General Order, on behalf of the City of Downey.
SECTION 4. The City Clerk shall certify to the adoption of this Resolution .
APPROVED AND ADOPTED this 8th day of August, 2023.
CLAUDIA FROMETA, Mayor
ATTEST:
MARIA ALICIA DUARTE, CMC
City Clerk
I HEREBY CERTIFY that the foregoing Resolution was adopted by the City Council of the City of Downey at a regular meeting held on the 8th day of August, 2023, by the following vote, to wit:
AYES: Council Members:
NOES: Council Member:
ABSENT: Council Member:
ABSTAIN: Council Member:
MARIA ALICIA DUARTE, CMC
City Clerk
ATTACHMENT A
City of Downey
Sewer System Management Plan
Prepared by:
May 2023
EXHIBIT A
May 2023
Table of Contents
Introduction ............................................................................................................................. i Background .................................................................................................................................. i Organization of SSMP .................................................................................................................. i Definitions, Acronyms, and Abbreviations ................................................................................... ii References ................................................................................................................................. v Chapter 1 Sewer System Management Plan Goal and Introduction .............................1-1
1.1 Regulatory Requirements for the Goals Element ..........................................................1-1
1.2 Sewer System Management Plan Update Schedule .....................................................1-1
1.3 Sewer System Asset Overview .....................................................................................1-2 Chapter 2 Organization ....................................................................................................2-1
2.1 Regulatory Requirements for Organization Element .....................................................2-1
2.2 Authorized Representative ...........................................................................................2-1
2.3 Responsibility for SSMP Development, Implementation, and Maintenance ..................2-1
2.4 Organization Chart .......................................................................................................2-2
2.5 Spill Reporting Chain of Communication ......................................................................2-2 Appendix 2-A: List of City Staff Responsible for SSMP ........................................................2-5 Appendix 2-B: Utilities Division Organization Chart ..............................................................2-6 Chapter 3 Legal Authority................................................................................................3-1
3.1 Regulatory Requirements for the Legal Authority Element............................................3-1
3.2 City Municipal Code ......................................................................................................3-1
3.3 Agreements with Other Agencies .................................................................................3-2 Chapter 4 Operations and Maintenance Program ..........................................................4-1
4.1 Regulatory Requirements for Operation and Maintenance Program Element ...............4-1
4.2 Collection System Mapping ..........................................................................................4-1
4.3 Preventive Operation and Maintenance Activities .........................................................4-2
4.4 Rehabilitation and Replacement Plan ...........................................................................4-4
4.5 Training Program ..........................................................................................................4-5
4.6 Equipment and Parts Inventory ....................................................................................4-6
4.7 References ...................................................................................................................4-6 Appendix 4-A: Sample GIS Update/Correction Form ............................................................4-7 Appendix 4-B: Standard Operating Procedure for Sewer Cleaning.......................................4-8 Appendix 4-C: Sewer Cleaning/Inspection CMMS .............................................................. 4-11 Appendix 4-D: Standard Measures of Observed Results .................................................... 4-12 Appendix 4-E: Sample Manhole Inspection Form ............................................................... 4-13 Appendix 4-F: Lift Station Condition Assessment Checklist................................................ 4-14 Appendix 4-G: Major Collection System Equipment Inventory ............................................ 4-17 Appendix 4-H: Critical Collection System Replacement Parts Inventory ............................. 4-18 Appendix 4-I: Root Control Maintenance Locations .......................................................... 4-19 Chapter 5 Design and Performance Provisions .............................................................5-1
5.1 Regulatory Requirements for the Design and Performance Provisions Element ...........5-1
5.2 Standard Specifications for Sanitary Sewer Facilities ...................................................5-1 Chapter 6 Spill Emergency Response Plan ....................................................................6-1
6.1 Regulatory Requirements .............................................................................................6-1
6.2 Goals of the Spill Emergency Response Plan ...............................................................6-2
6.3 Spill Detection ..............................................................................................................6-2
6.4 Spill Response Procedures ..........................................................................................6-4
May 2023
6.5 Public Notification ....................................................................................................... 6-14
6.6 Sewer Spill Categories ............................................................................................... 6-14
6.7 Sewer Spill Documentation and Reporting ................................................................. 6-15
6.8 Failure Analysis Investigation ..................................................................................... 6-15
6.9 External Sewer Spill Reporting Procedures ................................................................ 6-16
6.10 Equipment .................................................................................................................. 6-20
6.11 Sewer Spill Response Training ................................................................................... 6-21
6.12 Contractors Working on City Sewer Facilities ............................................................. 6-21 Appendix 6-A: Sewage Spill Response and General Telephone Numbers ......................... 6-22 Appendix 6-B: Sanitary Sewer Problem Report Form ......................................................... 6-23 Appendix 6-C: Sewer Spill Building History Form ............................................................... 6-25 Appendix 6-D: Collection System Failure Analysis Form .................................................... 6-26 Appendix 6-E: Methods for Estimating Spill Volume ........................................................... 6-27 Appendix 6-F: Manhole Spill Flowrate Guide ..................................................................... 6-30 Appendix 6-G: Sample Warning Sign ................................................................................. 6-31 Chapter 7 Sewer Pipe Blockage Control Program .........................................................7-1
7.1 Regulatory Requirements for the Sewer Pipe Blockage Control Program Element .......7-1
7.2 Nature and Extent of FOG Problem ..............................................................................7-1
7.3 Public Outreach Program .............................................................................................7-2
7.4 Sewer Pipe Blockage Source Control Program ............................................................7-3
7.5 FOG Disposal Facilities ................................................................................................7-5 Appendix 7-A: Sewer Lines Included in FOG Hotspot Program ............................................7-6 Appendix 7-B: Restaurants in Stormwater Inspection Program ............................................7-8 Appendix 7-C: Grease Haulers and FOG Disposal Facilities .............................................. 7-14 Chapter 8 System Evaluation, Capacity Assurance and Capital Improvements .........8-1
8.1 Regulatory Requirements for the System Evaluation and Capacity Assurance Plan Element....................................................................................................................................8-1
8.2 System Evaluation and Capacity Assessment ..............................................................8-2
8.3 Design Criteria ..............................................................................................................8-3
8.4 Capacity Enhancement Measures and Corrective Action .............................................8-3
8.5 Capital Improvement Plan ............................................................................................8-4 Chapter 9 Monitoring, Measurement, and Program Modifications ...............................9-1
9.1 Regulatory Requirements for the Monitoring, Measurement, and Program Modifications Element....................................................................................................................................9-1
9.2 Performance Measures ................................................................................................9-1
9.3 Historical Performance Data .........................................................................................9-1
9.4 Baseline Performance ..................................................................................................9-1
9.5 Performance Monitoring and Program Changes ...........................................................9-5 Appendix 9-A: Historical SSO Baseline Data January 2, 2007 – April 30, 2009 ...................9-6 Chapter 10 Internal Audits ............................................................................................... 10-1
10.1 Regulatory Requirements for the SSMP Audits Element ............................................ 10-1
10.2 SSMP Audits .............................................................................................................. 10-1
10.3 SSMP Updates ........................................................................................................... 10-2 Appendix 10-A: SSMP Audit Checklist ............................................................................. 10-3 Chapter 11 Communication Program ............................................................................. 11-1
11.1 Regulatory Requirements for the Communication Plan Element................................. 11-1
11.2 Communication Plan .................................................................................................. 11-1
11.3 Communication of Sanitary Sewer System Performance ............................................ 11-1
May 2023
11.4 Communication with Tributary/Satellite Sanitary Sewer Systems ............................... 11-2
List of Tables
Table 4-1: Training Resources (Conferences, Seminars, and Courses) ...................... 4-5 Table 4-2: Training Resources (Materials) ..................................................................... 4-6 Table 7-1: Analysis of FOG-Related SSO Data (January 1, 2018 – May 5, 2023) ......... 7-2 Table 7-2: Summary of Sewer Pipe Blockage Control Program Activities .................. 7-5 Table 8-1: FY 2023/24 – FY 2027/28 Five Year Capital Improvement Program ............ 8-4 Table 9-1: Baseline Performance (January 2, 2007 – April 30, 2009) ........................... 9-2 Table 9-2: Baseline Performance of Region 4 Agencies Between 150 and 250 miles of Sewer Mains (January 2, 2007 – April 30, 2009) .......................................................... 9-2 Table 9-3: Current Performance (January 1, 2018 – May 2023) .................................... 9-3 Table 9-4: Current Performance of Region 4 Agencies Between 150 and 250 miles of Sewer Mains (January 1, 2018 – May 2023) ................................................................. 9-3
List of Figures
Figure 1-1: City of Downey Sanitary Sewer Collection System and Service Area ....... 1-3 Figure 2-1: Spill Reporting Chain of Communication Overview .................................... 2-4 Figure 4-1: Sewer Cleaning Scheduling Flowchart......................................................... 4-3 Figure 6-1: Spill Response Procedure Flow Chart ......................................................... 6-5 Figure 6-2: Spill Response Flow Chart for City-Owned Sewer SSOs: Field Crew Activities ........................................................................................................................ 6-6 Figure 6-3: Spill Response Flow Chart for City-Owned Sewer Spills: Follow-Up Activities ........................................................................................................................ 6-7 Figure 6-4: Spill Response Flow Chart for Private Lateral/System SSOs ..................... 6-8 Figure 6-5: Spill Response Flow Chart for Spills in Sewers Not Owned by City .......... 6-9 Figure 6-6: External Reporting Requirement Checklist and Contact Information ...... 6-18 Figure 7-1: Location of Sewers Cleaned Frequently to Prevent FOG-Related Spills ... 7-3 Figure 7-2: Location of Sewers Cleaned Frequently to Prevent FOG-Related SSOs and Relationship to Restaurants ......................................................................................... 7-4 Figure 9-1: SSO Rate of Region 4 Agencies Between 150-250 miles of Sewer Mains (January 2, 2007 – April 30, 2009) ................................................................................ 9-4 Figure 9-2: SSO Rate of Region 4 Agencies Between 150-250 miles of Sewer Mains (January 1, 2018 – May 2023) ........................................................................................ 9-5 Figure 11-1: Best Practices for Reducing FOG Sewer Blockages and Spills ........... 11-3
May 2023
Appendices
A System Evaluation and Capacity Assurance Plan
B Sewer Rehabilitation and Replacement Plan
C Sanitary Sewer Facilities Design Guidelines, Policies, and Procedures D Sampling Procedures (SOP No. SSO01)
E Sewer Maintenance (SOP No. SM01)
F Spill Emergency Response Plan (SOP No. SER01)
G Water Quality Monitoring Program (SOP No. WQM01)
City of Downey SSMP Introduction
May 2023 i
Introduction
Background
This Sewer System Management Plan (SSMP) has been prepared in compliance with the State Water Resources Control Board (SWRCB) Order 2022-0102-DWQ: Statewide General Waste Discharge Requirements General Order for Sanitary Sewer Systems dated December 6, 2022. The order takes effect on June 5, 2023.
This SSMP is based in part on the previous SSMP prepared by RMC Water and Environment and Larson Consulting with assistance from the City of Downey. The SSMP is required to be updated every six years to reflect changes to the SSMP elements that have been implemented since the earlier version, and to comply with the latest SWRCB order.
Organization of SSMP
The structure of this document follows the section numbering and nomenclature specified in the Board Order. The SSMP includes eleven sections, as follows:
1. SSMP Goal and Introduction
2. Organization
3. Legal Authority
4. Operation and Maintenance Program
5. Design and Performance Provisions
6. Spill Emergency Response Plan
7. Sewer Pipe Blockage Control Program
8. System Evaluation, Capacity Assurance and Capital Improvements
9. Monitoring, Measurement, and Program Modifications
10. Internal Audits
11. Communication Program
City of Downey SSMP Introduction
May 2023 ii
Definitions, Acronyms, and Abbreviations
Best Management Practices (BMP) - Refers to the procedures employed in commercial kitchens to minimize the quantity of grease that is discharged to the sanitary sewer system. Examples include scraping food scraps into the garbage can and dry wiping dishes and utensils prior to washing.
Building Sewer - Refers to the piping that conveys sewage within a building or residence.
Calendar Year (CY)
California Integrated Water Quality System (CIWQS) - Refers to the State Water Resources Control Board online electronic reporting system that is used to report SSOs, certify completion of the SSMP, and provide information on the sanitary sewer system.
Capital Improvement Program (CIP) - Refers to the document that identifies planned capital improvements to the City’s sanitary sewer collection system.
Certification of SSO Reports - The SWRCB requires the Legally Responsible Official or authorized representative to login to CIWQS within a given time period to electronically sign submitted reports thereby stating that to the best of his/her knowledge and belief, the information submitted is true, accurate, and complete.
City - Refers to the City of Downey.
Closed Circuit Television (CCTV) - Refers to the process and equipment that is used to internally inspect the condition of gravity sewers.
Collection System – See Sanitary Sewer Collection System Computerized Maintenance Management System (CMMS) - Refers to software and a database that is used to manage maintenance and condition assessment data including the production of work orders and the recording of work completed.
Los Angeles County Sanitation Districts (LACSD)
Environmental Protection Agency (EPA) - Refers to the United States Environmental Protection Agency Fats, Oils, and Grease (FOG) - Refers to fats, oils, and grease typically associated with food preparation and cooking activities that can cause blockages in the sanitary sewer system.
Field Report - Refers to the Sanitary Sewer Problem Report Form.
Fiscal Year (FY) – Refers to the City of Downey Fiscal Year (July 1 to June 30).
Food Service Establishment (FSE) - Refers to commercial or industrial facilities where food is handled/prepared/served that discharge to the sanitary sewer collection system.
Force Main - Refers to a pressure sewer used to convey wastewater from a lift station to the point of discharge.
Full-time Equivalent (FTE) - Refers to the equivalent of 2,080 paid labor hours per year by a regular, temporary, or contract employee.
General Waste Discharge Requirements (GWDR) - Refers to the State Water Resources Control Board Order No. WQ 2022-0103-DWQ, Statewide General Waste Discharge Requirements for Sanitary Sewer Systems, dated December 6, 2022.
Geographical Information System (GIS) - Refers to the City’s system that it uses to capture, store, analyze, and manage geospatial data associated with the City’s sanitary sewer collection system assets.
City of Downey SSMP Introduction
May 2023 iii
Global Positioning System (GPS) - Refers to a handheld unit used to determine the longitude and latitude of sanitary sewer spills for use in meeting the Online SSO Reporting System reporting requirements.
Grease Removal Device (GRD) - Refers to grease traps or grease interceptors that are installed to remove FOG from the sanitary sewer flow at food service establishments.
Hotspot - A gravity sewer identified as requiring frequent preventive maintenance to reduce the likelihood of SSOs.
Infiltration/Inflow (I/I) - Refers to water that enters the sanitary sewer collection system from stormwater and groundwater that increases the quantity of flow. Infiltration enters through defects in the sanitary sewer collection system after flowing through the soil. Inflow enters the sanitary sewer without flowing through the soil. Typical points of inflow are holes in manhole lids and direct connections to the sanitary sewer (e.g. storm drains, area drains, and roof leaders).
Lateral - See sewer service lateral.
Legally Responsible Official (LRO) - Refers to the individual who has the authority to certify reports and other actions that are submitted through the Online SSO Reporting System.
Los Angeles County Department of Public Health (LAC DPH) Los Angeles Regional Water Quality Control Board (LARWQCB) - Refers to the Regional Water Quality Control Board for Region 4.
Manhole (MH) - Refers to an engineered structure that is intended to provide access to a sanitary sewer for maintenance and inspection.
Monitoring, Measurement, and Program Modifications (MMPM) Municipal Separate Storm Sewer Systems (MS4)
North American Industry Classification System (NAICS)
National Pollution Discharge Elimination System (NPDES) Not Applicable (NA)
Notification of an SSO - Refers to the time at which the City becomes aware of an SSO event through observation or notification by the public or other source.
Office of Emergency Services (OES) - Refers to the California Governor’s Office of Emergency Services.
Online SSO Reporting System - Refers to the California Integrated Water Quality System (CIWQS).
Operations and Maintenance (O&M)
Spill Emergency Response Plan (SERP)
Personal Protective Equipment (PPE)
Preventative Maintenance (PM) - Refers to maintenance activities intended to prevent failures of the sanitary sewer collection system facilities (e.g. cleaning, CCTV, inspection).
Private Lateral Sewage Discharges - Sewage discharges that are caused by blockages or other problems within a privately owned lateral.
Property Damage Overflow - Property damage spill refers to a sewer spill or backup that damages private property.
Pump Station - Used interchangeably with the term lift station.
City of Downey SSMP Introduction
May 2023 iv
Sanitary Sewer Collection System - Refers to the portion of the sanitary sewer facilities that are owned and operated by the City of Downey.
Sanitary Sewer Overflow (SSO) - Any overflow, spill, release, discharge or diversion of untreated or partially treated sewage from a sanitary sewer system. SSOs include:
(i) Spills or releases of untreated or partially treated wastewater that reach waters of the United States; (ii) Spills or releases of untreated or partially treated wastewater that do not reach waters of the United States; and
(iii) Wastewater backups into buildings and on private property that are caused by blockages or flow conditions within the publicly owned portion of a sanitary sewer system.
Sensitive Area - Refers to areas where a sewer spill could result in a fish kill or pose an imminent or substantial danger to human health (e.g. parks, aquatic habitats, etc.) Sewer Service Lateral - Refers to the piping that conveys sewage from the building to the City’s sanitary sewer collection system.
Sewer System - See Sanitary Sewer Collection System.
Sewer System Management Plan (SSMP)
Standard Operating Procedures (SOP) - Refers to written procedures that pertain to specific activities employed in the operation and maintenance of the sanitary sewer collection system.
State Water Resources Control Board (SWRCB) - Refers to the California Environmental Protection Agency (EPA) State Water Resources Control Board and staff responsible for protecting the State’s water resources.
Supervisory Control and Data Acquisition (SCADA) - Refers to an electronic system that is used to monitor lift station performance and to initiate alarms when monitored parameters exceed pre-set limits.
Surface Waters - See water of the State.
System Evaluation and Capacity Assurance Plan (SECAP)
Vitrified Clay Pipe (VCP) – Pipe commonly used to convey sanitary sewage in sanitary sewer collection systems.
Volume Captured - The amount of spilled sewage that is returned to the sanitary sewer collection system.
When recording the volume that is captured, the volume of water used for flushing and/or cleaning should not be included.
Water Body - A water body is any stream, creek, river, pond, impoundment, lagoon, wetland, or bay.
Waters of the State - Waters of the State (or waters of the United States) means any water, surface or underground, including saline waters, within the boundaries of California. In case of a sewage spill, storm drains are considered to be waters of the State unless the sewage is completely contained and returned to the sanitary sewer collection system and that portion of the storm drain is cleaned.
Work Order (WO) - Refers to a document (paper or electronic) that is used to assign work and to record the results of the work.
City of Downey SSMP Introduction
May 2023 v
References
State Water Resources Control Board Order No. WQ 2022-0103-DWQ Statewide Waste Discharge Requirements General Order for Sanitary Sewer Systems, California State Water Resources Control Board, December 6, 2022.
State Water Resources Control Board Order No. 2006-0003 Statewide General Waste Discharge Requirements for Sanitary Sewer Systems, California State Water Resources Control Board, May 2, 2006.
Monitoring and Reporting Program 2006-0003 Statewide General Waste Discharge Requirements for Sanitary Sewer Systems, State Water Resources Control Board, May 2, 2006 ( www.waterboards.ca.gov/board_decisions/adopted_orders/water_quality/2008/wqo/wqo2008_0002_exe c.pdf).
State Water Resources Control Board Monitoring and Reporting Program No. 2006·0003-DWQ (as revised by Order No. WQ 2008-0002.EXEC) Statewide General Waste Discharge Requirements for Sanitary Sewer Systems, California State Water Resources Control Board, February 20, 2008.
California Regional Water Quality Control Board, Los Angeles Region, Order No. 01-182, NPDES Permit No. CAS004001, Waste Discharge Requirements for Municipal Storm Water and Urban Runoff Discharges Within the County of Los Angeles, and the Incorporated Cities Therein, Except the City of Long Beach, December 13, 2001 (Amended on September 14, 2006 by Order RA-2006-0074).
City of Downey SSMP Chapter 1 Sewer System
Management Plan Goal and
Introduction
May 2023 1-1
Chapter 1 Sewer System Management Plan Goal and
Introduction
This section of the SSMP presents the City’s goals for the management, operation, and maintenance of its sanitary sewer collection system.
1.1 Regulatory Requirements for the Goals Element
The goal of the SSMP is to provide a plan and schedule to properly manage, operate, and maintain all parts of the City of Downey’s sanitary sewer system. This will help reduce and prevent emergency spills, as well as mitigate any sewage spills that do occur. The plan complies with the SWRCB Order WQ 2022-0103- DWQ and will be periodically updated in accordance with the requirements of the order.
The goals of the City of Downey SSMP are:
1. To properly manage, operate, and maintain all portions of the City’s sanitary sewer collection system.
2. To provide adequate capacity to convey the peak sanitary sewer flows. Adequate capacity, for the purposes of this SSMP, is defined as the capacity to convey the peak sanitary sewer flows that are associated with the design storm event.
3. To minimize the frequency of sewage spills and, wherever possible, prevent emergency spills.
4. To mitigate the impacts that are associated with any sewer spills that may occur.
5. To meet all applicable regulatory notification and reporting requirements.
6. To provide the funding, personnel, and equipment necessary to adequately manage, operate, and maintain all portions of the City’s sanitary sewer collection system.
7. To provide the funding and personnel necessary to implement capital improvements to provide adequate capacity to convey peak sanitary sewer flows and rehabilitate/replace sewer infrastructure.
1.2 Sewer System Management Plan Update Schedule
In accordance with the latest board order, the City of Downey is required to update the SSMP every six (6) years. For municipal systems serving populations greater than 100,000, the first update under the last order is due on May 2, 2025. It is the intent of this updated sewer management plan to comply with the May 2, 2025 due date. Additionally, this updated SSMP is complying with the SSMP upload requirements to the CIWQS Sanitary Sewer System Database in June 2023. It is anticipated that the next SSMP update will be submitted to the State in May 2031.
Annual internal audits for existing enrollees are also required to be submitted to the State every three (3) years. The updated internal audit is to be submitted within six (6) months after the end of the prior 3-year audit period. The City recently completed an internal audit report in April 2023. It is expected to be submitted to the State sometime in the next few months. Assuming it is submitted by September 2023, then the next internal audit report will be due within six months after the 3-year audit period, or sometime in February to March 2027.
City of Downey SSMP Chapter 1 Sewer System
Management Plan Goal and
Introduction
May 2023 1-2
1.3 Sewer System Asset Overview
The City of Downey (City or Downey) owns, operates, and maintains the sanitary sewer collection system that serves the Downey area. The population as of the 2020 census is approximately 113,000. The City’s serves a 12.5 square mile area.
The wastewater generated in Downey is collected by trunk sewers owned, operated, and maintained by the Los Angeles County Sanitation Districts (LACSD). City of Pico Rivera and Downey sewer flows are also conveyed through the City of Downey via approximately 1,500 linear feet of sewer main (ownership of which is presently unknown) before entering a LACSD trunk sewer.
The City’s portion of the sanitary sewer collection system consists of approximately 193 miles of sanitary sewer mains, 4,250 manholes, and one lift station. There are approximately 22,500 sewer accounts. The sewer mains range in size from 6 to 21 inches in diameter as shown in Figure I-1.
The sewer main material is nearly exclusively vitrified clay pipe (VCP). The majority of the sewer main was installed between 1945 and 1955, with some sewers dating back to 1927. The City also owns and operates the Blandwood Road and True Avenue lift station which was constructed in 2017 and replaced two older lift stations.
City of Downey SSMP Chapter 1 Sewer System
Management Plan Goal and
Introduction
May 2023 1-3
Figure 1-1: City of Downey Sanitary Sewer Collection System and Service Area
City of Downey SSMP Chapter 2 Organization
May 2023 2-1
Chapter 2 Organization
The intent of this section of the SSMP is to identify City staff responsible for implementing the SSMP, responding to sewer spill events, and meeting the spill emergency reporting requirements. This section also includes the designation of the Authorized Representative to meet SWRCB requirements for completing and certifying spill reports.
2.1 Regulatory Requirements for Organization Element
The requirements for the Organization element of the SSMP are summarized below. The SSMP must identify:
(a) The name of the legally responsible or authorized representative; (b) The position titles, names, telephone numbers, and emails for management, administrative, and maintenance positions responsible for implementing specific elements in the SSMP program. (c) Organizational lines of authority; and
(d) The chain of communication for reporting spills from receipt of a complaint or other information, including the person responsible for reporting spills to the State and Regional Water Board and other agencies if applicable (such as County Health Officer, County Environmental Health Agency, Regional Water Board, and/or State Office of Emergency Services (OES)).
2.2 Authorized Representative
The City’s Authorized Representative, having overall responsibility for sanitary sewer collection system matters, is the Deputy Director of Public Works – Utilities Division.
To ensure efficiency and expediency in meeting the General Waste Discharge Requirements (GWDR), both the Deputy Director of Public Works/Utilities Manager and the Utilities Superintendent have been delegated the Legally Responsible Officials (LROs), an Authorized Representative having responsibility for the day to day operation of the City’s sanitary sewer collection system and associated documentation and reporting requirements, including but not limited to verbal notification, as well as electronic and written reporting to the Los Angeles County Department of Public Health (LAC DPH), Regional Water Quality Control Board (LARWQCB), SWRCB, and OES.
Due to the role of the Sewer and Stormwater Supervisor or On-Call Utilities Personnel as first responder in the event of a sewage spill, they are authorized to act as the Authorized Representative in the absence of the Deputy Director of Public Works/Utilities Manager and Utilities Superintendent. Such responsibility includes meeting sanitary sewer collection system documentation and reporting requirements including but not limited to verbal notification, as well as electronic and written reporting to the LAC DPH, LARWQCB, SWRCB, and OES.
2.3 Responsibility for SSMP Development, Implementation, and Maintenance
The City’s Deputy Director of Public Works – Utilities Division has responsibility for development, implementation, and maintenance of all elements of the City’s SSMP. The Deputy Director of Public Works may delegate responsibility for day-to-day implementation and maintenance of the City’s SSMP to City staff.
The Utilities Superintendent has responsibility for day-to-day development, implementation, and maintenance of the City’s Operation and Maintenance Program, Spill Emergency Response Plan,
City of Downey SSMP Chapter 2 Organization
May 2023 2-2
Monitoring, Measurement, and Program Modifications, and SSMP Program Audits. The Utilities Superintendent in turn utilizes the Sewer and Stormwater Supervisor and other Utilities Division operations staff as necessary to accomplish these tasks.
The Director of Public Works plans, organizes, and directs public works activities and associated budgets for the City. This includes advising City Management and City Council on public works matters including those related to the sanitary sewer collection system. It is the responsibility of City Council and Legal Council to establish new and amend existing ordinances and policies governing municipal operations through recommendations by City Management. This includes ordinances and policies related to the sanitary sewer collection system.
Other Public Works staff involved with developing, implementing, and maintaining the City’s SSMP, along with their job titles and contact information, are listed in Appendix 2-A.
2.4 Organization Chart
The Utilities Division organization chart identifying lines of authority and staff responsible for management, operation, and maintenance of City utilities including the sanitary sewer collection system is provided in Appendix 2-B.
2.5 Spill Reporting Chain of Communication
The Spill Emergency Reporting Chain of Communication follows the typical flow of information depicted in Figure 2-1. The Spill Emergency Reporting process and responsibilities are described in greater detail in Chapter 6 - Spill Emergency Response Plan.
The following provides a brief summary of this process and associated responsibilities:
There are various ways in which a potential spill can be detected. Detections may include public observation, receipt of a sewer lift station alarm via the City’s Supervisory Control and Data Acquisition (SCADA) system, or observation by City staff. Upon detection of a potential spill by the public, the City is typically notified via a phone call to the Public Works Engineering Division or Utilities Yard during normal working hours or a phone call to the Fire Department or Police Department after hours.
Upon detection and City notification, general information (i.e. time, location, nature of problem, etc.) about the potential spill is forwarded to the Sewer and Stormwater Supervisor or On-Call Utilities Contact. It is the responsibility of the Sewer and Stormwater Supervisor or On-Call Utilities Contact to:
a. Contact the reporting party
b. Investigate the site
c. Determine the cause of the problem
d. Request reinforcement if necessary
e. Notify responsible owner or agency if SSO is not caused by the City’s collection system f. Contain and mitigate
g. Correct the spill and clean-up
h. Notify the Director of Public Works, Deputy Director of Public Works, Utilities Superintendent, LAC DPH, and OES (if ≥ 1,000 gallons) of the situation
i. Complete the Sanitary Sewer Problem Report Form
Upon completion, the Sanitary Sewer Problem Report Form would be forwarded by the Sewer and Stormwater Supervisor or On-Call Utilities Contact to the Deputy Director of Public Works and Utilities Superintendent. The Deputy Director of Public Works and Utilities Superintendent have primary responsibility for any follow-up reporting and notification of regulatory agencies including but
City of Downey SSMP Chapter 2 Organization
May 2023 2-3
not limited to notification of the LARWQCB (to satisfy the 2-Hour/24-Hour reporting requirement), and electronic certified reporting via the online California Integrated Water Quality System (CIWQS) (or email should the online system be down). The Sewer and Stormwater Supervisor is authorized to perform such reporting in the absence of the Deputy Director of Public Works and Utilities Superintendent.
City of Downey SSMP Chapter 2 Organization
May 2023 2-4
Figure 2-1: Spill Reporting Chain of Communication Overview
City of Downey SSMP Chapter 2 Organization
May 2023 2-5
Appendix 2-A: List of City Staff Responsible for SSMP
Job Title Name
Work
Phone
Number
email
Director of Public Works Matt Baumgardner (562)904-7102 [email protected] Deputy Director of Public
Works Dan Mueller (562)904-7110 [email protected]
Superintendent of Utilities Matt Robertson (562)904-7202 [email protected] Water Systems Supervisor II -
Sewer and Stormwater Kenny Soto (562)904-7202 [email protected] On-Call Utilities
(after hours) Standby (562)448-8936 -
City of Downey SSMP Chapter 2 Organization May 2023 2-6 Appendix 2-B: Utilities Division Organization Chart
City of Downey SSMP Chapter 3 Legal Authority
May 2023 3-1
Chapter 3 Legal Authority
This section of the SSMP discusses the City’s legal authority to comply with the SSMP requirements, as provided in its Municipal Code and agreements with other agencies.
3.1 Regulatory Requirements for the Legal Authority Element The requirements for the Legal Authority element of the SSMP are summarized below:
The City must demonstrate, through collection system use ordinances, service agreements, or other legally binding procedures, that it possesses the necessary legal authority to:
(a) Prevent illicit discharges into its sanitary sewer collection system (examples may include infiltration and inflow (I/I), unauthorized storm water, chemical dumping, unauthorized debris, roots, fats, oils and grease; and trash, including rags and other debris that may cause blockages;) (b) Collaborate with stormwater agencies to coordinate emergency spill responses, ensure access to stormwater systems during spill events, and prevent unintentional cross connections of sanitary sewer infrastructure to stormwater infrastructure;
(c) Require that sewer system components and connections be properly designed and constructed; (d) Ensure access for maintenance, inspection, and/or repairs for portions of the service lateral owned or maintained by the Public Agency;
(e) Enforce any violation of its sewer ordinances, service agreements, or other legally binding procedures;
(f) Obtain easement accessibility agreements for locations requiring sewer system operations and maintenance, as applicable.
3.2 City Municipal Code
The legal authority required for the City to comply with the SSMP requirements is contained within the City’s Municipal Code. Article 7, Chapter 2 of the Municipal Code is dedicated to sanitary sewers and industrial waste. ( https://library.qcode.us/lib/downey_ca/pub/municipal_code/item/article_vii-chapter_2) .
The items included in Article 7, Chapter 2 of the Municipal Code are discussed in more detail below as they pertain to prevention of illicit discharges, proper design and construction of sewer mains and connections, maintenance access, and enforcement measures.
3.2.1 Prevention of Illicit Discharges
Measures to prohibit illicit discharges are included in the Municipal Code’s Section 7272, Prohibited Waste Discharges. The specific purpose of the section is to prevent the discharge of any pollutant or any combination of pollutants into the sewers that would obstruct or damage the collection system, interfere with treatment, or threaten harm to human health or the environment. Additionally, Section 7242 prohibits the opening or entering of any manholes and Section 7244 prohibits the discharge of any cesspool effluent directly into a manhole or other opening in the City’s collection system, except pursuant to special permission issued by the City for such discharge. Section 7246 also provides limitation for discharge of any materials that may clog, obstruct, fill or interfere with or prevent the operation of the sewer system.
Examples of discharges covered in the Municipal Code are included below. Refer to Article 7, Chapter 2 of the Municipal Code for the complete text.
City of Downey SSMP Chapter 3 Legal Authority
May 2023 3-2
Stormwater: Section 7238 prohibits discharge of any rainwater, stormwater, groundwater, street drainage, yard drainage, water from yard fountains, ponds or lawn sprays, or any other uncontaminated water into any sewerage facility owned and maintained by the City.
Industrial Waste: Section 7262 states that both LACSD and the City jointly issue permits for industrial wastewater disposal, with LACSD having ultimate authority with regard to the quality and quantity of the discharge. A permit is required and must be approved by the City and LACSD.
Fats, Oils, Grease (FOG): Section 7272.14 prohibits the discharge of any dispersed biodegradable oils, fats and greases, such as lard, tallow, or vegetable oil in excessive concentrations that would tend to cause adverse effects on the sewerage system. Article 8, Chapter 4 of the Municipal Code adopts the California Plumbing Code in its entirety. The California Plumbing Code Chapter 10, Section 1001.0 through 1017.2 specifies requirements for the installation of grease removal devices (GRDs) and design standards for GRDs.
3.2.2 Proper Design and Construction of Sewers and Connections Section 7204 requires that all plans required for the construction of sewers and laterals shall conform to the standards of design on file in the office of the City Engineer and be prepared by, or under the direction of, and signed by a Registered Civil Engineer of the State. Section 7210 provides for inspections and for approval of the City Engineer for all sewer work. Details on City requirements pertaining to the design, construction, and inspection of public and private sewer systems, constructing sewers, and connections are included in a separate document, titled “City of Downey Standard Specifications for Sanitary Sewer Facilities”. The requirements established in this document are discussed in further detail in Chapter 5 of this SSMP.
3.2.3 Lateral Maintenance
Section 7214.14 defines a house lateral as that part of the sewer piping within the street or right-of-way which extends from the property or sewer right-of-way line to a connection with the main line sewer for the purpose of conveying domestic sewage. Section 7240.2 requires that all laterals, industrial connection sewers, and appurtenances thereto shall be maintained in a safe and sanitary condition by the owner of the property served. The City does not own nor is it responsible for maintaining any portion of private sewer laterals connected to public sewer mains.
3.2.4 Enforcement Measures
Enforcement measures are available to City staff for enforcement of sewer provisions, as described in Article 7 of the Municipal Code. Section 7202 directs the City Engineer and the Director of Public Works or their delegated employees to administer, implement, and enforce the provisions of Chapter 7.
3.3 Agreements with Other Agencies
The SSMP requirements for legal authority are fulfilled by the City’s Municipal Code. However, the City does have additional legal agreements with other agencies, which are described in this section for reference.
3.3.1 Los Angeles County Sanitation Districts
The City entered into an agreement with the Los Angeles County Sanitation Districts of (LACSD) for the collection and treatment of the wastewater produced in the City. LACSD owns, operates, and maintains the trunk sewers that pass through and collect wastewater from the City. Per Section 7200.2 of Downey’s Municipal Code, LACSD’s wastewater ordinance requirements apply to all wastes discharged, deposited, or disposed of through direct connections to their facilities. Therefore, the City of Downey, as a satellite collection system to LACSD, must comply with all LACSD ordinances.
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May 2023 3-3
3.3.2 Control of I/I from Satellite Collection Systems
Although there are no known capacity problems due to I/I in the City’s system, the GWDR mandates that the City must demonstrate that it has the legal authority to control I/I into its collection system, including that from satellite systems. The City’s code prohibits illicit discharges, including extraneous stormwater, groundwater, or other drainage, which could be interpreted to apply to I/I. However, there are no specific provisions for controlling I/I or limiting peak wet weather flows that enter the City’s sewer system from satellite systems or from private laterals.
City of Pico Rivera and Downey sewer flows are conveyed through the City of Downey via approximately 1,500 linear feet of sewer main before entering a LACSD trunk sewer. The sewer line in question is maintained by Los Angeles County Department of Public Works Sewer Maintenance. However, ownership of this line is presently unknown. Therefore, the City has no known satellite systems. The City of Pico Rivera is subject to LACSD’s discharge prohibitions, which also include prohibitions against the discharge of stormwater and groundwater.
At this time, there does not appear to be an I/I problem from Pico Rivera (which in any case would affect only 1,510 feet of sewer main) that would justify an agreement related specifically to I/I control. There have been no capacity related sewer spills or overflows reported after rain events. The previously completed capacity analysis indicates that the flows from Pico Rivera are not an issue in the City.
City of Downey SSMP Chapter 4 Operations and Maintenance Program
May 2023 4-1
Chapter 4 Operations and Maintenance Program
This section of the SSMP presents the City’s sanitary sewer collection system operations and maintenance (O&M) program.
4.1 Regulatory Requirements for Operation and Maintenance Program Element
The summarized requirements for the Operations and Maintenance Program are:
(a) Maintain an up-to-date map of the sanitary sewer system, showing all gravity line segments and manholes, pumping facilities, pressure pipes and valves, and applicable storm water conveyance facilities;
(b) Describe routine preventive operation and maintenance activities by staff and contractors, including a system for scheduling regular maintenance and cleaning of the sanitary sewer system with more frequent cleaning and maintenance targeted at known problem areas. The Preventative Maintenance (PM) program should have a system to document scheduled and conducted activities, such as work orders;
(c) Develop a rehabilitation and replacement plan to identify and prioritize system deficiencies and implement short-term and long-term rehabilitation actions to address each deficiency. The program should include regular visual and TV inspections of manholes and sewer pipes, and a system for ranking the condition of sewer pipes and scheduling rehabilitation. Rehabilitation and replacement should focus on sewer pipes that are at risk of collapse or prone to more frequent blockages due to pipe defects. Finally, the rehabilitation and replacement plan should include a capital improvement plan that addresses proper management and protection of the infrastructure assets. The plan shall include a time schedule for implementing the short- and long-term plans plus a schedule for developing the funds needed for the capital improvement plan; (d) Provide training on a regular basis for staff in sanitary sewer system operations and maintenance, and require contractors to be appropriately trained; and (e) Provide equipment and replacement part inventories, including identification of critical replacement parts.
4.2 Collection System Mapping
The City has a Geographical Information System (GIS) it uses to create and maintain maps of its sanitary sewer collection system facilities. The GIS includes pipe and manhole inventory information including length, diameter, material, rim/invert elevations, street address, and other information. The GIS also includes information on the City’s and Los Angeles County Flood Control District’s storm drain systems.
The GIS information is available to appropriate City staff in the form of hard copy maps and interactively through the City’s Intranet via field tablets, mobile phone, or personal computer.
4.2.1 Updates to Existing Drawings
The field crews use hard copy maps (Atlas Map Sheets) that are produced using the GIS or views the maps using field tablets. . The hard copy maps are updated annually. The City has a formal process to correct its maps. Proposed corrections are identified by field crews and communicated to engineering staff using the GIS Data Updates/ Corrections/Modifications Reporting Form (Appendix 4-A) or red -lined directly into the iWater software using field tablets. High priority corrections (those that may result in poor decision-making and potentially leading to a spill or overflow) are entered into the GIS and updated map
City of Downey SSMP Chapter 4 Operations and Maintenance Program
May 2023 4-2
pages are issued within 60 days. Low priority corrections and new facilities are incorporated into the GIS and updated map pages are issued annually.
Record/As-Built Drawings for LACSD trunk sewers and City sewer mains, lift stations, and appurtenant facilities are available at the Public Works counter in hard copy form. In addition, the City scans sewer system Record/As-built Drawings and links the scanned images to the associated sewer facilities in the GIS.
These images are also available electronically to Public Works employees through the City’s Intranet via field tablets, mobile phone, or personal computer.
4.2.2 New Improvement Plan Drawings
Developers are required to prepare and submit Record Drawings upon installation of new City-owned sewer mains, storm drains, and associated facilities. The Record Drawings are submitted in both a hard copy and electronic format. The GIS is updated with Record Drawing information annually.
4.3 Preventive Operation and Maintenance Activities
The elements of the City’s sanitary sewer collection system Operation and Maintenance (O&M) Program include proactive, preventive, and corrective maintenance of gravity sewers, and periodic inspection and preventive maintenance of its lift station. The details of the City’s O&M Program are described in this section.
4.3.1 Gravity Sewers
The City proactively cleans its sanitary sewer collection system and purchased a CCTV van in 2020. The City preventively cleans Hotspot sewers (sewers with a history of maintenance needs) every 1, 3, 6, or 12 months. Hotspot sewers are identified during the Closed Circuit Television (CCTV) Inspection Program and the updated list is presented in Appendix 7-A. The previous Sewer Rehabilitation and Replacement Report also listed the initial hotspot sewer location (see Section 4.7 for reference). The additional Hotspot sewers total approximately 1,500 feet. One part-time sewer cleaning crew is currently assigned to sewer cleaning activities. The City’s standard operating procedure (SOP No. SM01) for sewer cleaning is included as Appendix 4-B; it includes the quality assurance measures that are followed by the City.
Gravity sewer maintenance is currently scheduled using lists of Hotspot sewers and collection system maps for system-wide cleaning. The City maintains a computer-based maintenance management system (CMMS) for use in work planning, work order generation, and recording completed work. The City has also used a paper-based work order system to record completed work. The City’s CMMS work order form used for dispatching work and recording completed work is shown in Appendix 4-C.
An important aspect of the City’s sewer cleaning program is that the cleaning results are recorded for each manhole-to-manhole pipe segment using code-based standard results (see Appendix 4-C). Those results then provide the basis for the Sewer and Stormwater Supervisor to modify the frequency or method of cleaning for that pipe segment to reflect current field conditions. Follow-up video inspections and/or repairs are requested as needed. This process is shown on Figure 4-1.
The City uses its own CCTV inspection equipment and crew to determine the primary causes of blockages and sewer spill events.
The City uses contractors for corrective maintenance on an as-needed basis. During emergencies, the Utilities Division field crews are used to complete repairs. The Utilities Division maintains a list of known structural deficiencies. The list is maintained in priority order. Urgent priority structural deficiencies which may cause an SSO are corrected as soon as possible.
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The City uses contractors to apply pesticides on an annual basis to control vectors (insects and rodents).
Sewers and appurtenant structures are treated as needed to control infestations noted during regular inspections or identified through complaints.
Figure 4-1: Sewer Cleaning Scheduling Flowchart
Clean Sewer
Report
Results
Review Results and
History:
Prior Results
Prior Frequency
Prior SSOs
Corrective Actions
CCTV Inspect
FOG Control
Maint. Access
Root Control
Chemical
Repair
Rehabilitate
Replace
Action
Needed?
Decide
Frequency
and Method
Complete
Action
No
Set Initial
Frequency
and Method
Continue
Scheduled
Maintenance
until Corrective
Action completeYes
And
The City applies root control chemicals on an as-needed basis in problematic areas in order to reduce the rate of root growth and subsequent structural damage to the pipe. The sewers that were identified during the CCTV Inspection Program and included in the initial chemical root control program are listed in the Sewer Rehabilitation and Replacement Report (see Appendix 4-I for reference). The total quantity identified was 11,800 feet. The application frequency is every 24 months. The pipe segments are cleaned approximately two months prior to application of the root control chemicals in order to remove major root masses and to allow time for some re-growth for optimal herbicide uptake. The optimal application period is during the hot, dry months (July through September).
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All programs and activities related to gravity sewers are the responsibility of the Sewer and Stormwater Supervisor.
4.3.2 Reactive Maintenance
Reactive maintenance activities include investigation and response to any complaints regarding a manhole spill, missing or shifted manhole covers, manhole covers that are excessively noisy, residential plumbing troubles, sewer odor, etc. Sewer complaints received by the Public Works Department are investigated and appropriate actions are taken to resolve the source of the problem.
If necessary, the City may plug sewer facilities of abandoned or condemned structures in order to limit the potential for cross flows between stormwater and sanitary sewer collection systems.
4.3.3 Lift Station
The City monitors the operation of its lift station using SCADA. The City conducts monthly operational inspections and the wet well is cleaned as needed monthly. Preventive maintenance for mechanical and electrical equipment is scheduled annually. Completed work is currently recorded using daily logs that are maintained by each of the operations and maintenance staff. The City also uses CMMS to plan work and to record completed work.
Operational inspections, response to alarms, and preventive/corrective maintenance are the responsibility of the Sewer and Stormwater Supervisor.
4.4 Rehabilitation and Replacement Plan
The City’s Rehabilitation and Replacement Program is driven by the condition of its sewer system assets.
The City conducted its initial condition assessment, including gravity sewers and lift stations, during 2007 and continues to assess the system on a regular basis during O&M activities in order to update the Sewer Rehabilitation and Replacement Plan (See Appendix C).
4.4.1 Gravity Sewers
The results of the initial gravity sewer condition assessment are included in the Sewer Rehabilitation and Replacement Report (see Section 4.7 for reference). Future gravity sewer condition assessments are based on CCTV inspection and system-wide cleaning programs on an annual basis. The details of the CCTV Inspection Program are included in the Sewer Rehabilitation and Replacement Report.
The City assesses the condition of its manholes and other structures using City field crews and visual inspection methods during its system-wide sewer cleaning. A sample manhole inspection form is included as Appendix 4-E.
Gravity sewers that were identified during the initial and subsequent assessments as requiring repair or rehabilitation are described in detail in the Sewer Rehabilitation and Replacement Report. The City periodically re-evaluates its priorities for gravity sewer repair and rehabilitation projects following completion of each annual condition assessment. The City will address the highest priority repair and rehabilitation projects during subsequent annual capital improvement programs with the goal of completing the highest priority projects within reasonable time frames.
4.4.2 Lift Stations
The Blandwood Road and True Avenue lift stations were demolished and consolidated into one lift station as part of Cash Contract No. 675 – Blandwood Road and True Avenue Sewer Lift Stations Replacement Project. The project was completed in July 2017. The project included replacement of the two 50 plus year old sewer lift stations along Blandwood Road and True Avenue in northeast Downey with one new sewer
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lift station to provide sewer service to that area. Replacement of the lift stations was necessary to ensure environmentally safe and reliable collection of sanitary sewage and to avoid potential for sewer overflows.
The work included but was not limited to: abandonment of the two existing sewer lift stations, manholes, and associated piping and equipment, installation of one new sewer lift station with two (one operational and one backup) submersible pumps with 7.5 horsepower motors, new wet well and emergency overflow manhole and associated bypass piping, 990 feet of new 4-inch sewer force main piping, 760 feet of new 8- inch gravity sewer main piping and new manholes, 469 feet of new 6-inch gravity sewer laterals, 8 new gravity sewer manholes and 3 force main cleanout sewer manholes, new valve vault with pipe connections, flow metering, controls and materials, and associated electrical improvements.
4.2.2.1 Lift Station Condition Assessments
The design and construction of the new lift station was completed in 2017. The future lift station condition assessments will be based on the checklist included in Appendix 4-F. The results will be used to identify major maintenance and capital improvement projects. The lift station condition assessment will be conducted every five to 7 years.
The City’s operations staff performs preventative maintenance of the lift station that consists of the following:
Daily - Review SCADA and look for pump or seal failures
Monthly
- Visual inspection of control panel
- Inspect wet well and wash down system
- Monitor grease buildup
- Clean as needed
- Inspect backflow for the well wash system for any leaks and tampering
Yearly
- Pull apart check valve to clean, inspect, and lubricate as necessary - Fully pump out wet well and vacuum solids
- Test back flow for the well wash system
4.5 Training Program
4.5.1 City Staff
The City uses a combination of on-the-job training, conferences, seminars, and other training opportunities to provide technical training for its sanitary sewer collection system staff. Vendors provide training for new equipment. The Utilities Division budget includes funds for technical training. The sources of technical training and training materials for the City’s sanitary sewer collection staff are listed on Tables 4- 1 and 4-2.
Table 4-1: Training Resources (Conferences, Seminars, and Courses) Sponsor Event Timeframe References
California Water Environment
Association
State Conference April
www.cwea.org Southern Regional
Safety Conference May
Southern Collection
Systems Committee Quarterly
Southern California Alliance of
Publicly Owned Treatment
Works
Collection System
Committee Quarterly www.scap1.org
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Tri-State Conference Annual Conference September www.tristateseminar.com Cuyamaca College,
El Cajon On-Campus Courses www.cuyamaca.edu/wwtr/
courses.asp
UC Riverside Extension
Certification Exam
Review Course
ENSC 814.3
www.extension.ucr.edu/
Table 4-2: Training Resources (Materials)
Sponsor Materials Reference
California State University,
Sacramento
Videos, manuals, home study
courses www.owp.csus.edu
Other potential sources of training include the Los Angeles Chapter of the American Public Works Association and the Southern California Chapter of the Maintenance Superintendents Association.
Individual training records are maintained by the Utilities Division using a spreadsheet.
4.5.2 Contractor Employees Working on City Sewer Projects The City amended its contract language for sewer projects to require contractors working on the sanitary sewer collection system to employ workers with experience in sanitary sewer collection systems and/or to provide training regarding the impact of their project on the operation of the wastewater collection. All contractors working on City sewer facilities are required to develop a project-specific SERP or review the City’s SERP, to provide project personnel with training regarding the content of the SERP and their role in the event of a spill event, and to follow that SERP in the event that they cause or observe a spill.
4.6 Equipment and Parts Inventory
The list of the major equipment that the City uses in the operation and maintenance of its sanitary sewer collection system is included in Appendix 4-G. The Critical Replacement Parts Inventory is included in Appendix 4-H. At this time, the City does not keep an inventory of replacement parts, and is able to obtain parts on an as-needed basis.
4.7 References
Blandwood Road and True Avenue Lift Station Replacement Project No. CC-675, Steven Andrews Engineering Record Drawing Plans and Specifications, 2017.
City of Downey Sewer Rehabilitation and Replacement Report, Final Report, Tetra Tech, May 2023.
Sewer Lift Station Condition Evaluation, Technical Memorandum, RMC Water and Environment, April 29, 2009.
Blandwood Road and True Avenue Lift Station Replacement Evaluation, Technical Memorandum, RMC Water and Environment, April 29, 2009.
Hydroflush Best Practices Manual, California Collection System Collaborative Benchmarking Group, February 2001.
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Appendix 4-A: Sample GIS Update/Correction Form
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Appendix 4-B: Standard Operating Procedure for Sewer Cleaning Purpose
The purpose of this Standard Operating Procedure (No. SM01) is to ensure that sewer cleaning is performed in a manner that will produce a high-quality work product. Quality is important because it ensures that the sanitary sewers will not experience problems prior to their next scheduled cleaning.
Goal
The goal of cleaning a gravity sewer is to restore the flow area to 95% of the original flow area of the pipe.
Required Equipment and Tools
1. Personal protective equipment (hardhat, steel toe boots, rubber gloves, leather gloves, eye/face protection, hearing protection);
2. First Aid Kit
3. Calibrated gas detectors;
4. Safety cones, barricades, flags, signs, and/or other traffic control devices;
5. Sewer Atlas map book, I-Water Tablet;
6. Hydro-Jetting Cleaning Unit;
7. “Grenade Bomb” cleaning nozzle, “Chisel Point” penetrating nozzle, “Root Cutter” nozzle, “Warthog” cleaning nozzle or “Bulldog” cleaning nozzle;
8. Six-wire skid (“proofer”) in sizes that will be encountered during the day;
9. Debris trap baskets in the sizes that will be encountered during the day;
10. Extra fiber glass poles in various lengths;
11. Pole shovel, pole guider hook;
12. Manhole hook or pick-axe/bar;
13. Manhole roller;
14. Sandbags, Pipe Plugs
15. Measuring wheel, tape measure;
16. Push broom, square and/or round point shovels;
17. Sledge hammer;
18. Allen wrench set, pipe wrenches, adjustable wrenches, pliers;
19. Power tools (grinder, drill, impact and Sawzall)
20. Flashlights, mirrors;
21. Roll of “Duct” tape;
22. Razor blade knives; and
23. Corks
Procedures for Supervisor
1. Assign crew’s work at least three days in advance, when possible.
2. Determine if there are any special traffic conditions that need to be addressed for the assignment.
For heavy traffic areas, plan traffic control in advance so that ample traffic control devices and
City of Downey SSMP Chapter 4 Operations and Maintenance Program
May 2023 4-9
personnel can be transported to the jobsite. Give at least 24 hours notice to any business that will be adversely impacted by traffic control or the cleaning operations.
3. Identify the schedule for cleaning. When possible, cleaning operations should be conducted during normal business hours. When in residential areas, cleaning operations should not begin before 8 a.m. nor continue after 5 p.m. unless there is an emergency that warrants working outside of these hours. Door hangers shall be put out the day prior to any cleaning in a residential area when the cleaning will occur before 8 a.m. or after 5 p.m.
Procedures for Sewer Cleaning Crew
Prior to Leaving the Utilities Yard
1. Plan the work so that it starts in the upstream portion of the area and moves downstream.
2. Wherever possible, plan to clean sewers from the downstream manhole.
3. Inspect the sewer cleaning nozzles for wear. Replace nozzles that are excessively worn.
4. If this is the crew’s first day with this cleaning unit, inspect the first 200 feet of hose and couplings for damage or wear.
5. Fill the water tank with water. Operator must fill up tank prior to end of shift.
At the Jobsite
1. Wear proper personnel protective equipment (PPE).
2. Determine and confirm location of upstream and downstream manholes (use street addresses, the Sewer Atlas map book or I-Water Tablet).
3. Look for any overhead utilities that may come into contact with fiber glass poles or the vacuum boom during the cleaning operation.
4. Set up proper traffic control by placing traffic signs, flags, cones, and other traffic control devices.
5. Move the cleaning unit into the traffic control so that the hose reel is positioned over the manhole.
6. Open the manhole and use the gas detector to determine if it safe to proceed with the cleaning operation.
7. Install the “Warthog” nozzle or other cleaning nozzle (based on the job) on the hose.
Cleaning Operation
1. Insert the debris trap basket.
2. Start the engine/auxiliary engine.
3. Lower the hose, with the guider hook into the manhole and direct it into the sewer to be cleaned.
4. Position the manhole roller over the manhole and put the hose in between the manhole roller to protect the hose.
5. Open the water valve, start the high-pressure lift/valve and set the engine speed/RPMs to provide adequate pressure for the sewer cleaning operation.
6. Allow the hose to proceed up the sewer main, the hose speed should not exceed 20 feet per minute.
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7. Allow the hose to proceed 25% of the length of the sewer and pull the hose back.
8. Observe the nature and the quantity of the debris pulled back to the manhole.
9. If there is little or no debris, allow the hose to proceed to the upstream manhole.
10. If there is moderate to heavy debris, clean the remaining portion of the sewer in steps not to exceed 25% of the length of the sewer.
11. Open the upstream manhole and verify that the nozzle is at or past the manhole.
12. The sewer has been adequately cleaned when:
• Successive passes with a cleaning nozzle do not produce any additional debris, and, • The sewer is able to pass a full size, six-wire skid (“proofer”) for its entire length.
13. Determine the nature and quantity of the debris removed during the cleaning operation. Use the codes in the following table to report the nature and quantity of debris. Appendix 4-D in the Sewer System Management Plan provides a more detailed description of each of the codes.
Type of Material Clear (no debris) Moderate Heavy
Debris (sand, grit, rock) CLR DM DH
Grease CLR GM GH
Roots CLR RM RH
Other: CLR OM OH
Source: Hydroflush Best Practices Manual, California Collaborative Benchmarking Group, 2001
14. Remove the debris from the manhole using the vacuum unit or by using the pole shovel to scoop/push the debris into the debris trap basket.
15. Rewind the hose on the reel.
16. Remove the debris trap basket.
17. Clean the mating surface and close the manhole. Ensure that the manhole is properly seated.
18. Enter the results on the Sewer Flushing Log sheet as well as the I-Water Tablet.
19. Move the cleaning unit, break down and stow the traffic control.
20. If needed, fill the water tank at or near the next location of work.
21. Proceed to the next cleaning jobsite.
At the End of the Day
1. Inspect the equipment and tools for problems.
2. Report any problems with equipment, tools, or sewers that were cleaned during the day that may require extra attention (CCTV or Repairs) to the Sewer and Storm Water Supervisor.
3. Return the I-Water Tablet to its port and sync the data collected throughout the day to the hard drive.
4. Turn in all completed Sewer Flushing Log sheets to the Sewer and Storm Water Supervisor at the end of the shift
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Appendix 4-C: Sewer Cleaning/Inspection CMMS
City of Downey
Gravity Sewer Maintenance
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Appendix 4-D: Standard Measures of Observed Results
Next to cleaning the sewer line, effective observation of results is the most important work product of the field crew. The information they provide is the basis for defining future maintenance activities. Consistency is important. The standards for “results” for small diameter (six- and eight-inch) sewers are:
Clear Moderate Heavy
Debris No
observable
debris
Less than 5 gallons of material
15-20 minutes to clean
1-2 passes required
Requires cleaning twice or less
per year
Only fine grit
More than 5 gallons of materials
More than 30 minutes to clean
More than 4 passes required
Requires cleaning four times per
year
Grease No
observable
grease
Small chunks/no “logs"
15-20 minutes to clean
1-2 passes required
Requires cleaning twice or less
per year
Big chunks/"logs”
Operator concern for downstream
plugging
More than 30 minutes to clean
More than 4 passes required
Roots No
observable
roots
Thin/stringy roots present
No large “clumps”
15-20 minutes to clean
1-2 passes required
Thick roots present
Large “clumps"
More than 30 minutes to clean
More than 4 passes required
Other condition
observations:
- Pipe material
fragments
- Soil/dirt
- Rock (pipe
bedding)
- Lost nozzle
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Appendix 4-E: Sample Manhole Inspection Form
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Appendix 4-F: Lift Station Condition Assessment Checklist Inspection Information
Inspection date
Inspection participants
Facility name
Facility address
Comments
Background Information (Prior 12 Months)
SSOs
Equipment failures
Alarm history (attach copy)
Major maintenance activities
(attach list if applicable)
Pending work orders (attach
copies)
Operating problems (attach
copy of operating log)
Comments
Security Features
Hatch/lid
Fence and gate (if applicable)
External lighting
Visibility from street
Doors and locks
Intrusion alarm(s)
Signs with emergency contact
information
Other security features
Comments
Safety Features and Equipment
Signage (confined space,
automatic equipment, hearing
protection, etc.)
Fall protection
Emergency communication
Equipment hand guards
Hand rails and kickboards
Platforms and grating
Tag out and lock out
equipment
Hearing protection
Eye wash
Chemical storage
Comments
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External Appearance
Vault
Fence (if applicable)
Landscaping (if applicable)
Building (if applicable)
Control panels
Other external features
Comments
Building/Structure
PS building
Control room
Dry well
Wet well
Other structures
Comments
Instrumentation and Controls (including SCADA Facilities) Control panel
Run time meters
Flow meter
Wet well level
Alarms
SCADA
Other instrumentation and
controls
Comments
Electrical and Switch Gear
Power drop
Transformers
Transfer switches
Emergency generator and
generator connection
Starters
Variable frequency drives
Electrical cabinets
Conduit and wireways
Other electrical
Comments
Motors
Lubrication
Insulation
Operating current
Vibration and alignment
Other
Comments
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Pumps
Lubrication
Vibration and alignment
Seals
Indicated flow and discharge
pressure
Shutoff head
Corrosion and leakage
evidence
Drive shaft
Other
Comments
Valves and Piping
Valve operation
Valve condition
Pipe condition
Pipe support
Other
Comments
Other
Lighting
Ventilation
Support systems (air, water,
etc.)
Signage
Employee facilities
Sump pump
Overhead crane
Portable pump connections
Portable pumps
Comments
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Appendix 4-G: Major Collection System Equipment Inventory
Inventory Date: May 2023
Inventory/Condition Checked by: Kenny Soto and Matt Robertson
Equipment
Number Major Equipment Type
Year
Purchased
3409 E-F450 CCTV Van 2020
3411 Pressure Washer Trailer 2022
3536 Trailer Hydro Jetter ½” 4000 psi 2017
3529 Freightliner Vac-con Combination unit. ¾” 3000psi 2018
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Appendix 4-H: Critical Collection System Replacement Parts Inventory
Inventory Date _________________________________________________________
Inventory/Condition Checked by ______________________________________________
Equipment
Number Major Equipment Type
Year
Purchased
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Appendix 4-I: Root Control Maintenance Locations
ID Area Location Length (ft)
1 63 Bangle Rd (between Guatemala Ave & 7866 Bangle
Rd) MH N0559 - MH N0554, 685.93ft 685
2 63 Alderdale St (between 7837 Alderdale St & Botany St) MH N0053 - MH N0460, 775ft 775
3 63 Botany St (between 7706 Botany St & Smallwood
Ave) MH N0543 - MH N0460, 752ft 752
4 63 Danvers St (between 7706 Danvers St & Smallwood
Ave) MH N0558 - MH N0459, 902ft 920
5 62,
63,
79 Bairnsdale St (between 7706 Bairnsdale St &
Smallwood Ave) MH N2081 - MH N0458, 1,050ft 1,050
6 63,
79 Smallwood Ave (between Bairnsdale St & Botanny St)
MH N0458 - MH N0460, 545ft 545
7 62,
63,
79 Allengrove St (between Guatemala Ave & Tweedy Ln)
MH N2398 - MH N0464, 1565.28ft 1,565
8 78 Coolgrove Dr (between 7606 Coolgrove Dr & Horley
Ave) MH N1922 - MH N1920, 570ft 570
9 78 Shadyoak Dr (between 7606 Shadyoak Dr & Horley
Ave) MH N2113 - MH N2110, 725ft 725
10 78 Finevale Dr (between 7506 Finevale Dr & Horley Ave) MH N2118 - MH N2122, 787ft 787
11 78 Calmcrest Dr (between 7506 Calmcrest Dr & Horley
Ave) MH N2105 - MH N2101, 1,200ft 1,200
12 77 Ivo St (between Guatemala Ave & Norlain Ave) MH
N2167 - MH N2230, 340.22ft 340
13 77,
93 Norlain Ave (between Ivo St & Lubec St) MH N2230 -
MH N2228, 521.68ft 521
14 96,
109
Manzanar Ave (between 9117 Manzanar Ave &
Gallatin Rd) MH N0131 - MH N0522, 994.88ft 995
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15 110 Arrington Ave (between 9129 Arrington Rd & Gallatin Rd) MH N0345 - MH N0342, 909.84ft 910
16 110
120
Haledon Rd(Between 9102 Haledon & Appleby St)
MH N0205 - MH N0352 801.33 FT
801
17 120 Appleby St (between 9339 Appleby St & Lemoran
Ave) MH N0821 - MH N0800, 391.73ft 392
18 130 Otto St (between 9217 Otto St & Garnish Dr) MH
N0927 - MH N0926, 240ft 240
19 130 Garnish Dr (between N Otto St & S Otto St) MH
N0926 - MH N0925, 138ft 138
20 118 Dolan Ave (between 9914 Dolan Ave & Dinsdale St) MH N0262 - MH N1046, 590ft 590
21 160 Buell St (between 9514 Buell St & Lesterford Ave) MH N1839 - MH N1836, 813ft 813
22 92 Irwingrove Dr (between Sherry Ave & Alley) MH
N2301 - MH N2298, 1058.86ft 1,058
23 135 Brookmill Rd (between 7733 Brookmill Rd & 7621
Brookmill Rd) MH N2847 - MH N2514, 686ft 686
24 145 Cleta St (between 7986 Cleta St & Pruess Ave) MH N2604 - MH 2601, 634ft 634
25 145 Rives Ave (between Benares St & Luxor St) MH N2598 - MH N1526, 450ft 450
26 211 Laurelwood Ln (between 10260 Laurelwood Ln &
10228 Laurelwood Ln) MH N4031 - MH N4030, 350ft 350
27 196
12321 Woodruff Ave, Service Road (between
Woodruff Ave & MH N4198) MH N3942 - MH N4198,
929ft
929
28 211 Branscomb St (between 10263 Branscomb St &
Carfax Ave) MH N4019 - MH N4014, 345ft 345
29 225 Carfax Ave (between Priscila St & Branscomb St) MH N4008 - MH N 4014, 259ft 259
City of Downey SSMP Chapter 5 Design and Performance Provisions
May 2023 5-1
Chapter 5 Design and Performance Provisions
This section of the SSMP presents the City’s Design and Construction Standards.
5.1 Regulatory Requirements for the Design and Performance Provisions Element
The summarized requirements for the Design and Construction Standards element of the SSMP are:
(a) The City must have updated design criteria, and construction standards and specifications, for the construction, installation, repair, and rehabilitation of existing and proposed system infrastructure components, including but not limited to pipelines, pump stations, and other system appurtenances.
If existing design criteria and construction standards are deficient to address the necessary component-specific hydraulic capacity as specified in Section 8 (System Evaluation, Capacity Assurance and Capital Improvements) of this SSMP, the procedures must include component- specific evaluation of the design criteria.; and
(b) The City must also have procedures and standards for inspecting and testing the installation of newly constructed, newly installed, repaired and rehabilitated system sewer pipelines, pump stations, equipment and other appurtenances.
5.2 Standard Specifications for Sanitary Sewer Facilities Design standards and specifications for the installation, rehabilitation, and testing of new sanitary sewer collection systems, lift stations, and laterals is included in the “City of Downey Sanitary Sewer Facilities Design Guidelines, Policies, and Procedures”.
Technical specifications for typical sewer projects are included in the document in Appendix C. The City uses the standards listed in the Standard Specifications for Public Works Construction (Greenbook), latest edition, as well American Public Works Association (APWA) Standard Plans for Public Work Construction, latest edition. The standards included in LACSD’s Amendment to the Greenbook are also referenced.
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Chapter 6 Spill Emergency Response Plan
The purpose of the Spill Emergency Response Plan (SERP) is to support an orderly and effective response to Sanitary Sewer Overflows (SSOs) and sewer spills. This plan provides guidelines for City personnel to follow in responding to, cleaning up, and reporting spills that may occur within the City’s service area. The City has also prepared a Standard Operating Procedure SOP No. SER01 for implementation of the plan and is included in Appendix F.
6.1 Regulatory Requirements
6.1.1 GWDR Requirements for the Spill Emergency Response Plan The Plan must include an up-to-date Spill Emergency Response Plan to ensure prompt detection and response to spills to reduce spill volumes and collect information for prevention of future spills. The Spill Emergency Response Plan must include procedures to:
(a) Notify primary responders, appropriate local officials, and appropriate regulatory agencies of a spill in a timely manner;
(b) Notify other potentially affected entities (for example, health agencies, water suppliers, etc.) of spills that potentially affect public health or reach waters of the State; (c) Comply with the notification, monitoring and reporting requirements of this General Order, State law and regulations, and applicable Regional Water Board Orders; (d) Ensure that appropriate staff and contractors implement the Spill Emergency Response Plan and are appropriately trained;
(e) Address emergency system operations, traffic control and other necessary response activities; (f) Contain a spill and prevent/minimize discharge to waters of the State or any drainage conveyance system;
(g) Minimize and remediate public health impacts and adverse impacts on beneficial uses of waters of the State;
(h) Remove sewage from the drainage conveyance system;
(i) Clean the spill area and drainage conveyance system in a manner that does not inadvertently impact beneficial uses in the receiving waters;
(j) Implement technologies, practices, equipment, and interagency coordination to expedite spill containment and recovery;
(k) Implement pre-planned coordination and collaboration with storm drain agencies and other utility agencies/departments prior, during, and after a spill event; (l) Conduct post-spill assessments of spill response activities; (m) Document and report spill events as required in this General Order; and (n) Annually, review and assess effectiveness of the Spill Emergency Response Plan, and update the Plan as needed.
6.1.2 Regulatory Requirements for Municipal Separate Storm Sewer Systems (MS4s) The Federal Water Pollution Control Act and the Clean Water Act, as amended, give the US Environmental Protection Agency the authority to regulate the discharge of pollutants to Waters of the United States under the National Pollutant Discharge Elimination System (NPDES). That authority was expanded to include
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stormwater runoff in 1987. The City is required to comply with the MS4 / NPDES Permit for Los Angeles County. The 2021 NPDES/MS4 requires permittees to :
• Implement controls and measures to prevent and eliminate infiltration of seepage from sanitary sewers to MS4s through thorough, routine preventive maintenance of the MS4. • Implement controls and measures to prevent and eliminate infiltration of seepage from the sanitary sewers to the MS4s that must include overall sanitary sewer and MS4 surveys and thorough, routine preventive maintenance of both.
• Implement controls to prevent infiltration of seepage from sanitary sewers to the MS4 where necessary. Such controls must include:
o Adequate plan checking for construction and new development; o Incident response training for its municipal employees that identify sanitary sewer spills;
o Code enforcement inspections;
o MS4 maintenance and inspections;
o Interagency coordination with sewer agencies; and
o Proper education of its municipal staff and contractors conducting field operations on the MS4 or its municipal sanitary sewer (if applicable)
6.1.3 Stormwater Permit Requirements
The City’s NPDES/MS4 permit requires that the City continue to implement a spill response plan that includes procedures to prevent, contain, and respond to all sewage and other spills that may discharge into the MS4. The permittee shall report spills that may endanger health or the environment in accordance with California Water Code 13271.
6.2 Goals of the Spill Emergency Response Plan
The City’s goals with respect to responding to sewer spills are:
(a) Work safely;
(b) Respond quickly to minimize the volume of the spill; (c) Prevent sewage system spills or leaks from entering the storm drain system or receiving waters to the maximum extent practicable;
(d) Eliminate the cause of the spill;
(e) Contain the spilled wastewater to the extent feasible; (f) Minimize public contact with the spilled wastewater; (g) Mitigate the impact of the spill; and
(h) Meet the regulatory reporting requirements.
6.3 Spill Detection
The processes used to notify the City of the occurrence of a sewer spill include: observation by the public, receipt of an alarm, or observation by City staff during the normal course of their work.
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6.3.1 Public Observation and Emergency Communications
Public observation is the most common way that the City is notified of blockages and spills. Contact information for reporting sewer spills and backups is on the City’s website at www.downeyca.org . On the City’s website, the public is encouraged to call the appropriate party in the case of a sewer spill. The website includes contact information for both working hours and after-hours emergencies.
6.3.1.1 Normal Work Hours
When a report of a sewer spill or backup is received, Public Works Administration or Utilities Division/Yard staff receives the call, takes the information from the caller and communicates it to the Sewer and Stormwater Supervisor who responds to the site and/or dispatches a field crew. Reports received by the Fire Department or Police Department Dispatch, Public Works Administration, or other City Services offices are routed to the Utilities Division.
During regular Utilities Yard working hours (Mon – Fri, 6:30 a.m. – 4:00 p.m.) the three (3) Utilities Division crew members with the shortest response time and the Sewer and Stormwater Supervisor will respond to the emergency call. Usually, the Sewer and Stormwater Crew Member(s) closest to the site will respond first. This plan assumes that when responding to an emergency call, staff will usually have with them the necessary equipment and/or vehicles. Sewer and Stormwater staff maintain the following equipment and vehicles: Sewer Trailer, Combination Sewer Vacuum Truck, CCTV Inspection Van, Sewer Easement Rodder, safety equipment, and emergency response vehicles.
6.3.1.2 After Hours
After-hours emergency calls are received by Fire Department or Police Department Dispatch personnel who contact the Sewer and Stormwater Supervisor or On-Call Utilities Contact. Utilities Division staff are notified of an emergency call via dedicated after-hours cell phone. Home and/or cell telephone numbers of all Utilities Division staff are on file and available for use during emergencies.
During after-hours (Mon – Fri, 4:00 p.m. – 6:30 a.m. and Sat – Sun) the standby person will respond to the emergency call. The standby person is determined through a weekly rotation of crew members who serve on a one-week “on-call” basis. The standby person will respond to the call and call the Sewer and Stormwater Supervisor immediately. The Sewer and Stormwater Supervisor will request additional help, as needed. Although the standby person drives a Utilities vehicle to the site, he will occasionally need to arrange for additional equipment at the site.
Information from the emergency call is transcribed to the Sanitary Sewer Problem Report Form (Appendix 6-B).
6.3.1.3 City Website
The City’s website includes contact information for both working hours and after-hours emergencies.
6.3.2 Lift Station Alarms
The City’s lift station is equipped with a Supervisory Control and Data Acquisition System (SCADA) alarm system. The backup battery-equipped SCADA equipment detects and sends alarms in response to pump failures, high and low wet well levels, and power outages.
In addition, the lift station is equipped with local alarm lights and signs with the City’s contact information.
If the public observes a spill and/or local alarm light, they notify the Fire Department or Police Department Dispatch who in turn contact the Sewer and Stormwater Supervisor or On-Call Utilities Contact.
The lift station is located at 9726 Blandwood Road with electrical panel located at 9451 True Avenue.
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May 2023 6-4
During normal working hours, the SCADA equipment notifies the Sewer and Stormwater Supervisor through a personal computer, text/voice message, and email. After normal working hours, the Sewer and Stormwater Supervisor or other on-call Utilities Personnel are notified by the SCADA system through text/voice message.
6.3.3 City Staff Observation
Utilities Division staff conduct periodic inspections of sanitary sewer collection system facilities as part of their routine activities. Any problems noted with the sanitary sewer collection system facilities are reported to appropriate Utilities Division staff who respond to emergency situations. Sanitary sewer problems noted by other City staff conducting routine activities are reported via phone to the Public Works Administration or Utilities Yard who then forward this information to appropriate Utilities Division staff. Work orders are issued to correct non-emergency conditions.
6.4 Spill Response Procedures
Sewer service calls and lift station alarms are considered high priority events that demand a prompt response to the location of the problem. Upon notification of a spill, a sewer maintenance work crew shall be dispatched and is usually onsite within one hour of notification.
The response procedure flow charts for sewer spills that are caused by City-owned sewers, private laterals, and surrounding Agency sewers are depicted in Figures 6-1, 6-2, 6-3, 6-4, and 6-5.
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Figure 6-1: Spill Response Procedure Flow Chart
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Figure 6-2: Spill Response Flow Chart for City-Owned Sewer SSOs: Field Crew Activities
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May 2023 6-7
Figure 6-3: Spill Response Flow Chart for City-Owned Sewer Spills: Follow-Up Activities
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Figure 6-4: Spill Response Flow Chart for Private Lateral/System SSOs
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Figure 6-5: Spill Response Flow Chart for Spills in Sewers Not Owned by City
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May 2023 6-10
6.4.1 Safety
The Sewer and Stormwater Supervisor or On-Call Utilities Contact, as first responder, is responsible for following City safety procedures at all times.
There may be times when City personnel responding to a sanitary sewer collection system event are not fully familiar with potential safety hazards peculiar to sanitary sewer or SSO response work. In such cases it is appropriate to take the time to discuss safety issues, consider the order of work, and check safety equipment before starting the job.
6.4.1.1 Traffic Control
Traffic control requirements vary depending on the location and the risk to operating personnel and the public. CalTrans standards are the minimum for congested and/or high-speed streets and highways. The minimum traffic controls for low-speed/low-traffic-density streets should conform to the latest edition of the Manual of Uniform Traffic Control Devices (MUTCD). In the case where there are no local standards, the minimum traffic control should be:
(a) Warning signs (signs with the symbol for person working are preferred); (b) Directional arrow signs on front and rear of the truck; (c) Traffic cones clearly delineating traffic lanes and directions; and (d) One or more flaggers should be used to control and direct traffic where visibility is limited or the possibility of collision exits.
6.4.1.2 Hazardous Material Spills
On occasion City personnel may encounter a sewer spill that involves hazardous chemicals (e.g., flammable). In those instances, or in any instance where there is a reasonable doubt, they should immediately contact their Supervisor for instructions.
In the event the spill contains hazardous materials, the City of Downey Fire and Police Department dispatch should be notified immediately so that the Fire Department Hazardous Materials Response Team can be activated. Utilities Department personnel should remain on site and provide assistance to the Hazardous Materials Response Team. The type of assistance to be provided includes traffic control, plugging storm drains from a safe distance, and shutting down lift stations.
6.4.2 Sewer and Stormwater Supervisor or On-Call Utilities Contact Priorities The priorities of the Sewer and Stormwater Supervisor or On-Call Utilities Contact responding to a call are:
(a) To follow safe work practices;
(b) To contact the reporting party and collect as much information as possible; (c) To contact Los Angeles County Department of Public Health; (d) To respond promptly with appropriate equipment;
(e) To contain the spill wherever feasible;
(f) To restore the wastewater flow as soon as practicable; (g) To minimize public access to and/or contact with the spilled sewage; (h) To promptly notify the Director of Public Works, the Deputy Director of Public Works, and Utilities Superintendent in the event of an SSO;
(i) To return the spilled sewage to the sanitary sewer collection system; and (j) To restore the area to its original condition (or as close as possible).
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May 2023 6-11
6.4.3 Initial Response
The Sewer and Stormwater Supervisor or On-Call Utilities Contact calls the reporting party to clarify the situation and collect any additional information that may allow City personnel to respond in an efficient manner. The Sewer and Stormwater Supervisor or On-Call Utilities Contact should:
(a) Field verify the address and nearest cross street to determine whether the spill or backup is located in the City’s service area. If the location of the spill is not in the City’s service area, call the responsible agency, provide them with the service call information, and notify the caller that the responsible agency has been notified.
(b) Respond with the appropriate spill response vehicle that has spill containment tools and materials and any additional equipment that may be needed based on the details provided by the caller. a. Note arrival time at spill site.
b. If the initial inspection indicates that the discharging facility is not within the jurisdiction of the City of Downey or that the problem is not caused by the City’s sewer system, the responding crew is to report this information to the Sewer and Stormwater Supervisor, who will notify the appropriate agency staff and direct further field operations (See Appendix 6-A for contact information related to sewage spill response). (c) Regardless of whether the spill/backup is caused by a private lateral or other agency sewer system, the responding crew should contain/mitigate the spilled sewage to the extent feasible, and standby until representatives of the responsible party arrive and are fully operational. (d) Set up traffic and pedestrian control as necessary for safety of the public and the response crew. (e) Identify and assess the affected area and extent of spill. (f) Notify the Sewer and Stormwater Supervisor when:
a. The spill appears to be large, in a sensitive area, or there is doubt regarding the extent, impact, or how to proceed.
b. Additional help is needed, to get assistance contacting other employees, contractors, and/or equipment suppliers.
(g) If the spill is large or in a sensitive area, document conditions upon arrival with photographs. (h) Decide whether to proceed with clearing the blockage to restore the flow or to initiate containment measures. The guidance for this decision is:
a. Small spills – proceed with clearing the blockage.
b. Moderate or large spill where containment is anticipated to be simple – proceed with the containment measures.
c. Moderate or large spills where containment is anticipated to be difficult – proceed with clearing the blockage; however, call for additional assistance after 15 minutes without clearing the blockage and implement containment measures. (i) Notify Director of Public Works, the Deputy Director of Public Works, and Utilities Superintendent in event of any SSO.
(j) Contact caller to let them know you are on-site if time permits.
6.4.4 Initiate Spill Containment Measures
The responding crew should attempt to contain as much of the spilled sewage as possible using the following steps:
(a) Determine the immediate destination of the spilled sewage.
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(b) Contain/direct the spilled sewage above grade using absorbent, dike/dam, sandbags, earthen berms, storm drain inlet covers.
(c) If spilled sewage has entered storm drains, then attempt to contain the spilled sewage by plugging downstream storm drainage facilities.
(d) Contain/direct the spilled sewage using dike/dam, sandbags, or earthen berms in landscaped or undeveloped areas.
(e) Pump around the blockage/pipe failure/lift station to convey the wastewater to the nearest downstream manhole or facility.
If the spill is caused by a sewer lateral, City staff may shut off the water supply to that property when the wastewater endangers the public health. The Sewer and Stormwater Supervisor or the On-Call Utilities Contact should contact the Utilities Superintendent prior to proceeding with this course of action
6.4.5 Restore Flow
Using the appropriate cleaning tools, set up downstream of the blockage and hydro clean upstream from a clear manhole. Attempt to remove the blockage from the system and observe the flows to ensure that the blockage does not recur downstream.
If the blockage cannot be cleared within a reasonable time (15 minutes), or the sewer requires construction repairs to restore flow, then initiate further containment and/or bypass pumping.
If assistance is required, immediately contact the Sewer and Stormwater Supervisor who will, in turn, contact other employees, contractors, and equipment suppliers.
6.4.6 Recovery
The recovery phase begins when the flow has been restored and the spilled sewage has been contained to the extent possible. The SSO recovery procedures are:
6.4.6.1 Estimate the Volume of Spilled Sewage
Use the methods outlined in Appendix 6-E to estimate the volume of the spilled sewage. Wherever possible, document the estimate using photos of the SSO site before and during the recovery operation.
6.4.6.2 Recovery of Spilled Sewage
Vacuum up spilled sewage using the Hydro-Vac or pump the spilled sewage and any water used to flush the area and discharge it back into the sanitary sewer collection system. Wash water need not be counted for reporting spill volumes.
6.4.7 Water Quality Sampling and Testing
Water quality sampling and testing is required whenever 50,000 gallons or more of spilled sewage (excluding rinse water) from Category 1 Spills enters a water body to determine the extent and impact of the sewer spill. Spills from Categories 2, 3 and 4 require spill specific monitoring only. Procedures for sample collection shall be in accordance with the City’s SOP No. SSO01 and is included in Appendix D.
The water quality sampling procedures are:
(a) The Sewer and Stormwater Supervisor or On-Call Utilities Contact will collect samples. Samples should be collected as soon as possible after the discovery of the SSO event. a. When faced with a small SSO that can be easily contained, the flow should be restored and samples taken as soon as possible after flow has been restored. b. For larger SSOs, it may be necessary to delay sampling until additional personnel arrive.
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(b) The water quality samples should be collected from upstream of the spill, from the spill area, and downstream of the spill in flowing water (e.g. rivers). (c) Once collected, samples should be refrigerated and management advised of status. (d) The City will use a state-certified, commercial laboratory to analyze the samples to determine the nature and impact of the discharge. The basic analyses should include total coliform, fecal coliform, biochemical oxygen demand (BOD), dissolved oxygen, and ammonia nitrogen. (e) Additional samples will be taken to determine when posting of warning signs can be discontinued.
6.4.8 Clean Up and Disinfection
Clean up and disinfection procedures should be implemented to reduce the potential for human health issues and adverse environmental impacts that are associated with a sewer spill event. The procedures described are for dry weather conditions and should be modified as required for wet weather conditions. Where clean up is beyond the capabilities of City staff, a clean up contractor will be used.
6.4.8.1 Private Property
Offer assistance with clean up and advise resident or property owner of claim procedures when appropriate.
6.4.8.2 Hard Surface Areas
Collect all signs of sewage solids and sewage-related material either by hand or with the use of rakes and brooms. Wash down the affected area with clean water until the water runs clear. Take reasonable steps to contain and vacuum up the wastewater and return it to the sanitary sewer collection system. Disinfect all areas that were contaminated from the spill using the disinfectant solution of household bleach diluted 10:1 with water. Apply minimal amounts of the disinfectant solution using a hand sprayer. Document the volume and application method of disinfectant that was employed. Allow area to dry. Repeat the process if additional cleaning is required.
6.4.8.3 Landscaped and Unimproved Natural Vegetation
Collect all signs of sewage solids and sewage-related material either by hand or with the use of rakes and brooms.
Wash down the affected area with clean water until the water runs clear. The flushing volume should be approximately three times the estimated volume of the spill.
Either contain or vacuum up the wash water so that none is released. Return the wastewater to the sanitary sewer collection system to the extent possible.
Allow the area to dry. Repeat the process if additional cleaning is required.
6.4.8.4 Natural Waterways
California Department of Fish and Wildlife will provide the professional guidance needed to effectively clean up spills that occur in these sensitive environments. Utilities Division management should contact them to request their assistance.
Clean up should proceed quickly in order to minimize negative impact.
Any water that is used in the clean up should be de-chlorinated prior to use.
6.4.8.5 Wet Weather Modifications
Omit flushing and sampling during heavy storm events with heavy runoff where flushing is not required and sampling would not provide meaningful results.
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6.4.9 Follow Up Activities
If sewage has reached the storm drain system, the hydro-truck should be used to vacuum/pump out the catch basin and any other portion of the storm drain that may contain sewage.
In the event that an spill occurs at night, the location should also be inspected first thing the following day.
The operator should look for any signs of sewage solids and sewage-related material that may warrant additional clean up activities.
6.5 Public Notification
Post signs and place barricades, cones, traffic arrow board, and caution tape as needed to keep vehicles and pedestrians away from contact with spilled sewage. Do not remove the signs until directed by the Utilities Superintendent. A sample warning sign is included in Appendix 6-G.
Creeks, streams, and beaches that have been contaminated as a result of a sewer spill should have signs posted at visible access locations until the risk of contamination has subsided to acceptable background levels. The warning signs, once posted, should be checked every day to ensure that they are still in place.
Do not remove the signs until directed by the Utilities Superintendent.
Major spills may warrant broader public notice. The approval of the City Manager is required prior to contacting local media when significant areas may have been contaminated by sewage. News reporters shall be referred to the City Manager’s office for information regarding an SSO.
6.6 Sewer Spill Categories
The California State Water Resources Control Board (SWRCB) has established guidelines for classifying and reporting sewer spills. Reporting and documentation requirements vary based on the type of spill.
There are four (4) categories of sewer spills as defined by the SWRCB1:
• Category 1 Spill - A Category 1 spill is a spill of any volume of sewage from or caused by a sanitary sewer system regulated under this General Order that results in a discharge to: A surface water, including a surface water body that contains no flow or volume of water; or a drainage conveyance system that discharges to surface waters when the sewage is not fully captured and returned to the sanitary sewer system or disposed of properly. Any spill volume not recovered from a drainage conveyance system is considered a discharge to surface water, unless the drainage conveyance system discharges to a dedicated stormwater infiltration basin or facility. A spill from an Enrollee- owned and/or operated lateral that discharges to a surface water is a Category 1 spill; the Enrollee shall report all Category 1 spills per section 3.1 of Attachment E1 (Notification, Monitoring, Reporting and Recordkeeping Requirements) of this General Order. • Category 2 Spill - A Category 2 spill is a spill of 1,000 gallons or greater, from or caused by a sanitary sewer system regulated under this General Order that does not discharge to a surface water.
A spill of 1,000 gallons or greater that spills out of a lateral and is caused by a failure or blockage in the sanitary sewer system, is a Category 2 spill.
• Category 3 Spill - A Category 3 spill is a spill of equal to or greater than 50 gallons and less than 1,000 gallons, from or caused by a sanitary sewer system regulated under this General Order that does not discharge to a surface water. A spill of equal to or greater than 50 gallons and less than 1,000 gallons, that spills out of a lateral and is caused by a failure or blockage in the sanitary sewer system is a Category 3 spill.
1 State Water Resources Control Board Monitoring and Reporting Program No. 2022-0103-DWQ (Statewide Waste Discharge Requirements General Order for Sanitary Sewer Systems
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• Category 4 Spill - A Category 4 spill is a spill of less than 50 gallons, from or caused by a sanitary sewer system regulated under this General Order that does not discharge to a surface water. A spill of less than 50 gallons that spills out of a lateral and is caused by a failure or blockage in the sanitary sewer system is a Category 4 spill.
6.7 Sewer Spill Documentation and Reporting
All sewer spills should be thoroughly investigated and documented for use in managing the sanitary sewer collection system and meeting established reporting requirements. The procedures for investigating and documenting SSOs are:
6.7.1 Internal Sewer Spill Reporting Procedures
6.7.1.1 Category 1 Spills
The Sewer and Stormwater Supervisor or On-Call Utilities Contact will immediately notify the Utilities Superintendent who will notify the Director of Public Works and the Deputy Director of Public Works.
The Utilities Superintendent or his/her designee (Sewer and Stormwater Supervisor, On-Call Utilities Contact) will meet with field crew(s) at the site of the SSO event to assess the situation and to document the conditions with photos.
The Sewer and Stormwater Supervisor or On-Call Utilities Contact will fill out the Sanitary Sewer Problem Report Form and turn it in to the Utilities Superintendent and Deputy Director of Public Works upon returning to the Utilities Yard.
In the event of a very large spill or an overflow in a sensitive area, the Director of Public Works or Deputy Director of Public Works will notify the City Manager. The City Manager may notify the City Council.
6.7.1.2 Category 2, 3 and 4 Spills
The Sewer and Stormwater Supervisor or On-Call Utilities Contact will immediately notify the Utilities Superintendent who will notify the Director of Public Works and the Deputy Director of Public Works.
The Utilities Superintendent or his/her designee will determine whether to personally assess the situation.
The Sewer and Stormwater Supervisor or On-Call Utilities Contact will fill out the Sanitary Sewer Problem Report Form and turn it in to the Utilities Superintendent and Deputy Director of Public Works.
6.7.1.3 Private Lateral SSOs
If a Private Lateral sewage discharge is reported to the City, the Sewer and Stormwater Supervisor or On- Call Utilities Contact will immediately notify the Utilities Superintendent who may notify the Director of Public Works and the Deputy Director of Public Works.
The Sewer and Stormwater Supervisor or On-Call Utilities Contact will fill out the Sanitary Sewer Problem Report Form and turn it in to the Utilities Superintendent and Deputy Director of Public Works.
6.8 Failure Analysis Investigation
The objective of the failure analysis investigation is to determine the “root cause” of the SSO and to identify corrective action(s) needed that will reduce or eliminate potential for the SSO to recur.
The investigation should include reviewing all relevant data to determine appropriate corrective action(s) for the line segment. The investigation will be conducted by the Sewer and Stormwater Supervisor. The investigation should include:
(a) Reviewing and completing/correcting the Sanitary Sewer Problem Report Form;
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(b) Reviewing past maintenance records;
(c) Reviewing available photographs;
(d) Conducting a CCTV inspection to determine the condition of the line segment immediately following the SSO and reviewing the video and logs; and (e) Interviewing staff who responded to the spill.
The product of the failure analysis investigation should be the determination of the root cause and the identification of the corrective actions. The Collection System Failure Analysis Form (Appendix 6-D) should be used to document the investigation.
6.9 External Sewer Spill Reporting Procedures2
The California Integrated Water Quality System (CIWQS) Online SSO Reporting System should be used for reporting SSO information to the SWRCB whenever possible. A summary of external reporting requirements and contact information is included as Figure 6-6.
6.9.1 Category 1 Spills that reach Waters of the State
If a Category I spill results in a discharge to waters of the State (a drainage channel or surface water, if not fully recovered), the following notification/reporting requirements apply:
Within two (2) hours of notification of the spill event the Utilities Superintendent or his/her designee will:
Notify the Los Angeles Regional Water Quality Control Board (LARWQCB) by phone with a follow-up fax;
Notify OES (and obtain spill number for use in other reports); and Notify the Los Angeles County Department of Public Health (LAC DPH); Notify the California Department of Fish and Wildlife, as necessary.
Within 24 hours of notification of the spill event, the Utilities Superintendent or his/her designee will certify to the LARWQCB by phone with a follow-up fax, that OES and LAC DPH were notified.
Within three (3) business days of being notified of the spill event, the Utilities Superintendent or his/her designee will certify the initial report using the Online SSO Reporting System.
Within 15 calendar days of the conclusion of SSO response and remediation, the Utilities Superintendent or his/her designee will certify the final report using the Online SSO Reporting System.
Within 45 calendar days after the spill end date for a Category 1 spill in which 50,000 gallons or greater discharged to surface waters, submit Technical Report.
Within 90 calendar days after the spill end date submit Amended Spill Report.
The Deputy Director of Public Works or his/her designee will update the certified report as new or changed information becomes available. The updates can be submitted at any time and must be certified.
6.9.2 Category 2 Spills that do not reach Waters of the State Within two (2) hours of the City’s knowledge of a Category 2 spill of 1,000 gallons or greater, discharging or threatening to discharge to waters of the State: Notify California Office of Emergency Services and obtain a notification control number
Within 3 business days of being notified of the spill event, the Deputy Director of Public Works or his/her designee will certify the initial report using the Online SSO Reporting System.
2 State Water Resources Control Board Monitoring and Reporting Program No. WQ 2023·0103-DWQ Statewide Waste Discharge Requirements General Order for Sanitary Sewer Systems
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Within 15 calendar days of the conclusion of spill response and remediation, the Deputy Director of Public Works or his/her designee will certify the final report using the Online SSO Reporting System.
Within 90 calendar days after the spill end date submit Amended Spill Report.
The Deputy Director of Public Works or his/her designee will update the certified report as new or changed information becomes available. The updates can be submitted at any time and must be certified.
6.9.3 Category 3 Spills
Within 30 calendar days after the end of the calendar month in which the spill occurs, the Deputy Director of Public Works or his/her designee will submit a certified report using the Online CIWQS Reporting System. The report will include the information to meet the GWDR requirements.
Within 90 calendar days after the spill end date submit Amended Spill Report.
6.9.4 Category 4 Spills
If, during any calendar month, Category 4 spills occur, certify monthly, the estimated total spill volume exiting the sanitary sewer system, and the total number of all Category 4 spills into the online CIWQS Sanitary Sewer System Database, within 30 days after the end of the calendar month in which the spills occurred.
Upload and certify a report, in an acceptable digital format, of all Category 4 spills to the online CIWQS Sanitary Sewer System Database, by February 1st after the end of the calendar year in which the spills occur.
6.9.5 Private Lateral Sewage Discharges
The Deputy Director of Public Works or his/her designee may report private lateral spills using the Online CIWQS Reporting System specifying that the sewage discharge occurred and was caused by a private lateral and identifying the responsible party (other than the City), if known, by February 1st after the end of the calendar year in which the spills occur. Report a lateral spill of any volume that discharges to a surface water as a Category 1 spill.
6.9.6 No Spill Certification (Monthly)
If there are no spills during the calendar month, the Deputy Director of Public Works or his/her designee will submit and certify an electronic report that the City did not have any SSOs, within 30 days after the end of each calendar month.
6.9.7 Online Spill Reporting System (CIWQS) Not Available In the event that the Online Spill Reporting System is not available, the Deputy Director of Public Works or his/her designee will email [email protected] all required information to the LARWQCB office in accordance with the time schedules identified above. In such event, the City will submit the appropriate reports using the Online CIWQS Reporting System as soon as practical.
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Figure 6-6: External Reporting Requirement Checklist and Contact Information
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6.9.2 Internal Spill Documentation
6.9.2.1 Category 1 and 2 Sewer Spills
The Sewer and Stormwater Supervisor or On-Call Utilities Contact will complete the Sanitary Sewer Problem Report Form (Appendix 6-B) and provide copies to the Utilities Superintendent or his/her designee.
The Sewer and Stormwater Supervisor or On-Call Utilities Contact will complete the Sewer Spill Building History Form (Appendix 6-C) if an SSO has occurred in a residence or building.
The Utilities Superintendent or his/her designee will prepare a file for each individual sewer spill. The file should include the following information:
(a) Initial service call information;
(b) Sanitary Sewer Problem Report Form;
(c) Online SSO Reporting System form;
(d) Volume estimate;
(e) Map showing the spill location;
(f) Photographs of spill location;
(g) CCTV inspection data;
(h) Water quality sampling and test results, if applicable; (i) Failure analysis investigation results; and
(j) Any other forms related to the SSO.
6.9.2.2 Private Lateral Sewer Spills
The Sewer and Stormwater Supervisor or On-Call Utilities Contact will complete the Sanitary Sewer Problem Report Form and provide copies to Utilities Superintendent. The Sewer and Stormwater Supervisor or On-Call Utilities Contact will complete the Sewer Spill Building History Form if an SSO has occurred in a residence or building.
A separate file will be prepared for each individual SSO, at the Utilities Superintendent’s discretion. The file should include any relevant information from the above list.
6.9.3 External Sewer Spill Record Keeping Requirements3 The GWDR requires that individual SSO records be maintained by the City for a minimum of five years from the date of the SSO. This period may be extended when requested by a Regional Water Quality Control Board Executive Officer.
All records shall be made available for review upon State or Regional Water Board staff's request.
Records shall be retained for all SSOs, including but not limited to the following when applicable:
(a) Copy of Certified Online SSO Reporting System report(s); (b) All original recordings for continuous monitoring instrumentation; (c) Service call records and complaint logs of calls received by the City; (d) SSO calls;
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(e) SSO records;
(f) Steps that have been and will be taken to prevent the sewer spills from recurring and a schedule to implement those steps.
(g) Work orders, work completed, and any other maintenance records from the previous five years which are associated with responses and investigations of system problems related to sewer spills; (h) A list and description of complaints from customers or others from the previous five years; and (i) Documentation of performance and implementation measures for the previous five years.
If water quality samples are required by an environmental or health regulatory agency, or if voluntary monitoring is conducted by the City, as a result of any sewer spill, records of monitoring information shall include:
(a) The date, exact place, and time of sampling or measurements; (b) The individual(s) who performed the sampling or measurements; (c) The date(s) analyses were performed;
(d) The individual(s) who performed the analyses;
(e) The analytical technique or method used; and
(f) The results of such analyses.
6.9.4 Post Sewer Spill Event Debriefing
Every SSO event is an opportunity to evaluate the response and reporting procedures. Each spill event is unique, with its own elements and challenges including volume, cause, location, terrain, and other parameters.
As soon as possible after major SSO events, all of the participants, from the person who received the call to the last person to leave the site, should meet to review the procedures used and to discuss what worked and where improvements could be made in responding to and mitigating future SSO events. The results of the debriefing should be recorded and tracked to ensure the action items are completed.
6.10 Equipment
This section provides a list of specialized equipment that is required to support this Spill Emergency Response Plan.
Camera -- A digital or disposable camera is required to record the conditions upon arrival, during clean up, and upon departure.
Closed Circuit Television (CCTV) Inspection Unit – A CCTV Inspection Unit is required to determine the root cause for all SSOs from gravity sewers.
Combination Sewer Cleaning Truck -- A combination high velocity sewer cleaning truck with vacuum tank is required to clear blockages in gravity sewers, vacuum spilled sewage, and wash down the impacted area following the SSO event. A Trailer-Mounted Sewer Cleaner may be used in hard-to-reach areas such as alleys.
Emergency Response Truck -- A utility body pickup truck is required to store and transport the equipment needed to effectively respond to sewer emergencies. The equipment and tools should include containment and clean up materials: sandbags, barricades, cones, caution tape, signs, air plugs, rakes, drop-inlet mats, and plastic sheeting.
GPS (Global Positioning System) -- A hand held GPS unit can be used to determine the coordinates of spills for use in meeting LARWQCB SSO reporting requirements (alternative is to use Google Earth to determine coordinates).
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Portable Generators, Portable Pumps, Piping, and Hoses – Provide equipment as needed.
6.11 Sewer Spill Response Training
This section provides information on the training that is required to support this Spill Emergency Response Plan.
6.11.1 Initial and Annual Refresher Training
All City personnel who may have a role in responding to, reporting, and/or mitigating a sanitary sewer collection system spill should receive training on the contents of this SERP. All new employees should receive training before they are placed in a position where they may have to respond. Current employees should receive annual refresher training on this plan and the procedures to be followed.
6.11.2 Spill Response Drills
Periodic training drills should be held to ensure that employees are up to date on the procedures, the equipment is in working order, and the required materials are readily available. The training drills should cover scenarios typically observed during sewer related emergencies (e.g. mainline blockage, mainline failure, force main failure, lift station failure, and lateral blockage). The results and the observations during the drills should be recorded and action items should be tracked to ensure completion.
6.11.3 Spill Training Record Keeping
Records should be kept of all training that is provided in support of this plan. The records for all scheduled training courses and for each spill emergency response training event should include date, time, place, content, name of trainer(s), and names of attendees.
6.12 Contractors Working on City Sewer Facilities
All contractors working on City sewer facilities will be required to develop a project-specific SERP or review the City’s SERP, to provide project personnel with training regarding the content of the SERP and their role in the event of an SSO, and to follow that SERP in the event that they cause or observe an SSO.
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Appendix 6-A: Sewage Spill Response and General Telephone Numbers
Agency Number Time Contact
County of Los
Angeles DPW
800-303-0003
888-CLEANLA
24 Hours
24 Hours
Los Angeles County Department of Public
Works
LA County
Information 213-974-1234 7:00am - 5:00pm/M-F County Operator
LA County Public
Health 888-700-9995 8:00am - 5:00pm/M-F
LACSD Emergency
Response
562-437-6520
24 Hours
Business hours
OES 800-852-7550 24 Hours
LARWQCB 213-620-6373 24 Hour Phone
Fax (Follow-Up)
Ching To
[email protected]
CA Fish & Wildlife 858-467-4201
858-636-3160
Bell Gardens 562-806-7770 7:30am-5pm/M-TH,
7:30am-4pm/F
Public Works Department
Bellflower 562-866-9061 x290 24 Hours Sheriff, Lakewood Station Downey 562-904-7202 6:30 am – 4:00 pm/M-F Utilities Yard Downey 562-904-7102 4:00 pm – 5:30 pm/M-F Public Works Department Downey 562-904-7313 24 Hours Fire Department Dispatch
Downey 562-904-2363 24 Hours Police Department Dispatch Huntington Park 213-584-6253
213-587-5211
8am-5pm/M-TH
Non-business Hours
City Engineer Department
Police Department
Norwalk 562-929-5511
562-863-8711
6am-6pm/M-TH
Non-business Hours
Public Services Department
Sheriff - complaints desk
Paramount 562-220-2002
562-866-9061 x290
7:30-5:30pm/M-TH
Non-business Hours
Public Works Department
Sheriff, Lakewood Station
Pico Rivera 562-949-2421 24 Hours Sheriff - complaint desk Santa Fe Springs 562-944-9713
562-868-1711
8am-5pm/M-F
24 Hours
Fire Department, Santa Fe Springs
Fire Department, Downey Dispatch
South Gate 213-563-5400 24 Hours Police Department
Contact information for other surrounding agencies not included on this list can be found at:
https://pw.lacounty.gov/general/servicelocator/
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Appendix 6-B: Sanitary Sewer Problem Report Form
Sanitary Sewer Problem Report Form
For Office Use
Date: Call Received: am/pm Received by:
Caller's Name: Caller's Phone Number:
Caller's Address:
Location of Spill:
Cross Street:
Time & Names of Crew Members Contacted:
Description of Complaint:
Note: Provide Field Report, Gas Detector, Radio, GPS, Camera, and Video Camera to Collection System Employee upon Arrival
For Response Crew Use
Time Arrived at Site: Crew Names:
Asset #: Easement: Yes No Upstream Asset #:
Size of Line: Length of Line: Downstream Asset #:
Caller Contacted: Yes No Sunny Cloudy Rainy Weather: Rain for Several Days: _____days
Complete Remainder of Form if a Spill (SSO) has Occurred SSO Started: am/pm SSO Stopped: am/pm Duration: days/hrs Est. Total Volume: gallons Est. Returned to Collection System: gallons Est. Volume that Reached Surface Water, Drainage Channel, Not Recovered from Storm Drain:
Fish Killed: Yes No Estimation Method
Used:
Eyeball Est. Duration/Flowrate
Measured Vol. Other
SSO Source: Manhole Gravity Main Clean Out Private Lateral Lift Station: ______________ Other: _________________________ Final Spill Destination: Storm Drain Captured Storm Drain Building Yard/Land Surface Water No Waters Involved Other: _______________ Cause of Spill: Roots Grease Debris Vandalism Power Failure Construction Damage Capacity (Heavy Rain) Other: ________
Cleanup Method/Actions Taken:
Disinfection: Yes No Disinfection Amount/Type:
Time Cleanup Began: Time Cleanup Complete:
Signs Posted: Yes No No. of Signs: Barricaded: Yes No No. of Days Photos Taken: Digital Film Video Neighbors Notified: Yes No Samples Taken By: Location of Samples:
Water Quality Samples Analyzed for:
Total Coliform
Fecal Coliform
BOD
Dissolved Oxygen
Ammonia Nitrogen
Other:
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Receiving Waters Description:
SSO Magnitude:
Spill discharged to a drainage channel and/or surface water. SSO reached storm drain and not fully captured/returned to the sewer. SSO volume was 1,000 gallons or more.
Private property was damaged.
Private lateral was cause (not City sewer).
SSO caused by sewer owned by surrounding Agency (not City sewer).
Customer Notified Regarding Status: Yes No If no, why not:
List all Personnel Responding to Spill:
Additional Information:
Notifications
Agency Notified Contact Information Date/Time
OES OES Spill #
LARWQCB SSO Event ID
Los Angeles County Dept. of
Public Health
Los Angeles County Health
Hazardous Materials Spills
California Dept of Fish & Wildlife
Other
Name of Person making Notifications:
Sketch of Area: include manholes, intersections, location of stoppage, etc. Use back of page if needed.
This Report was Completed By: Date/Time:
This Report was Submitted To: Date/Time:
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Appendix 6-C: Sewer Spill Building History Form
Sewer Spill Building History Form
Time City staff arrived on-site: _________ Time cleaning contractor called:_____________ Date: Time: Employee Name:
Resident/Business: Property Manager(s):
Street Address: Street Address:
City, State and Zip: City, State and Zip:
Phone: Phone:
Cause of spill:
Location/Sewer: □ Street □ Rear easement □ Manhole# ________ to _________
□ Mainline □ Service line □ Double-wye
Damage: □ Black water □ Grey water □ Fresh water
Number of people living at residence:
Comments:
Cleaning services: □ Requested by Owner – Wait for cleaning contractor to arrive □ Declined by Owner
Approximate age of building: _______ # of bathrooms: ______ # of rooms/units affected:
_______
Approximate amount of spill: ___________ (gallons)
Approximate time sewage has been sitting: _______________(hours/days) Number of pictures taken:____________ Digital Film Video Does the customer have a backflow prevention device (BPD)? □ Yes □ No If yes, was the BPD operational at the time of the spill? □ Yes □ No Have there been any previous spills at this location? □ Yes □ No □ Unknown Type of flooring in the room(s)/unit(s) affected: □ Tile □ Carpet □ Wood □ Other:
Condition:
Has the resident/business had any plumbing work done recently? □ Yes □ No □ Unknown
If yes, please describe:
Are there baseboards: □ Yes □ No If yes, baseboard material:
____________________________
Condition of baseboards:
□ Baseboard bottom has tight seal with floor □ Baseboard has space between baseboard & wall □ Baseboard top has tight seal with wall □ Baseboard has space between bottom & floor Sketch the room(s)/unit(s) affected (shade the areas most heavily affected).
City of Downey SSMP Chapter 6 Spill Emergency Response Plan
May 2023 6-26
Appendix 6-D: Collection System Failure Analysis Form
Collection System Failure Analysis Form
Incident Report #: Prepared By:
SSO/Backup Information
Event Date/Time: Address:
Volume Spilled: Volume Recovered:
Cause
Summary of Historical SSOs/Backups/Service Calls/Other Problems Date Cause Date Last Cleaned Crew
Records Reviewed By: Record Review Date:
Summary of CCTV Information
CCTV Inspection Date: Tape Name/Number:
CCTV Tape Reviewed By: CCTV Review Date:
Observations:
Recommendations
No Changes or Repairs Required
Maintenance Equipment:
Maintenance Frequency:
Repair (Location and Type):
Add to Capital Improvement Rehabilitation/Replacement List: Yes No Supervisor Review Date: Superintendent Review Date:
City of Downey SSMP Chapter 6 Spill Emergency Response Plan
May 2023 6-27
Appendix 6-E: Methods for Estimating Spill Volume
A variety of approaches exist for estimating the volume of a sanitary sewer spill. This appendix documents the three methods that are most often employed. The person preparing the estimate should use the method most appropriate to the sewer spill in question and use the best information available.
Method 1 Eyeball Estimate
The volume of small spills can be estimated using an “eyeball estimate”. To use this method imagine the amount of water that would spill from a bucket or a barrel. A bucket contains 5 gallons and a barrel contains 50 gallons. If the spill is larger than 50 gallons, try to break the standing water into barrels and then multiply by 50 gallons. This method is useful for contained spills up to approximately 200 gallons.
Method 2 Measured Volume
The volume of most small spills that have been contained can be estimated using this method. The shape, dimensions, and the depth of the contained wastewater are needed. The shape and dimensions are used to calculate the area of the spills and the depth is used to calculate the volume.
Common Shapes and Dimensions
Step 1 Sketch the shape of the contained sewage (see figure above).
Step 2 Measure or pace off the dimensions.
Step 3 Measure the depth at several locations and select an average.
Step 4 Convert the dimensions, including depth, to feet.
Step 5 Calculate the area in square feet using the following formulas:
Rectangle: Area = length (feet) x width (feet)
Circle: Area = diameter (feet) x diameter (feet) x 0.79 Triangle: Area = base (feet) x height (feet) x 0.5
Step 6 Multiply the area (square feet) times the depth (in feet) to obtain the volume in cubic feet.
Step 7 Multiply the volume in cubic feet by 7.5 to convert it to gallons
RECTANGLE CIRCLE
TRIANGLEe
LENGTH
BASE
W
I
D
T
H
H
E
I
G
H
T
DIAMETER
City of Downey SSMP Chapter 6 Spill Emergency Response Plan
May 2023 6-28
Method 3 Duration and Flowrate
Calculating the volume of larger spills, where it is difficult or impossible to measure the area and depth, requires a different approach. In this method, separate estimates are made of the duration of the spill and the flowrate. The methods of estimating duration and flowrate are:
Duration: The duration is the elapsed time from the time the spill started to the time that the flow was restored.
Start Time: The start time is sometimes difficult to establish. Here are some approaches:
• Local residents can be used to establish start time. Inquire as to their observations. Spills that occur in rights-of-way are usually observed and reported promptly. Spills that occur out of the public view can go on longer. Sometimes observations like odors or sounds (e.g. water running in a normally dry creek bed) can be used to estimate the start time. • Changes in flow on a downstream flowmeter can be used to establish the start time. Typically the daily flow peaks are “cut off” or flattened by the loss of flow. This can be identified by comparing hourly flow data during the spill event with flow data from prior days. • Conditions at the spill site change over time. Initially there will be limited deposits of toilet paper and other sewage solids. After a few days to a week, the sewage solids form a light-colored residue.
After a few weeks to a month, the sewage solids turn dark. The quantity of toilet paper and other materials of sewage origin increase over time. These observations can be used to estimate the start time in the absence of other information. Taking photographs to document the observations can be helpful if questions arise later in the process.
• It is important to remember that spills may not be continuous. Blockages are not usually complete (some flow continues). In this case the spill would occur during the peak flow periods (typically 10:00 to 12:00 and 13:00 to 16:00 each day). Spills that occur due to peak flows in excess of capacity will occur only during, and for a short period after, heavy rainfall.
End Time: The end time is usually much easier to establish. Field crews on-site observe the “blow down” that occurs when the blockage has been removed. The “blow down” can also be observed in downstream flowmeters.
Flow Rate: The flowrate is the average flow that left the sanitary sewer collection system during the time of the spill.
There are three common ways to estimate the flowrate:
• The San Diego Manhole Flowrate Chart: This chart, included as Appendix 6-F, shows sewage flowing from manhole covers at a variety of flowrates. The observations of the field crew can be used to select the appropriate flowrate from the chart. If possible, photographs are useful in documenting the basis for the flowrate estimate.
• Flowmeter: Changes in flows in downstream flowmeters can be used to estimate the flowrate during the spill.
• Counting Connections: Once the location of the spill is known, the number of upstream connections can be determined from the sewer maps. Multiply the number of connections by 200 to 250 gallons per day per connection or 8 to 10 gallons per hour per connection.
For example:
22 upstream connections x 9 gallons per hour per connection = 198 gallons per hour / 60 minutes per hour
City of Downey SSMP Chapter 6 Spill Emergency Response Plan
May 2023 6-29
= 3.3 gallons per minute
Spill Volume: Once duration and flowrate have been estimated, the volume of the spill is the product of the duration in hours or days and the flowrate in gallons per hour or gallons per day.
For example:
Spill start time = 11:00
Spill end time = 14:00
Spill duration = 3 hours
3.3 gallons per minute x 3 hours x 60 minutes per hour
= 594 gallons
City of Downey SSMP Chapter 6 Spill Emergency Response Plan May 2023 6-30 Appendix 6-F: Manhole Spill Flowrate Guide
City of Downey SSMP Chapter 6 Spill Emergency Response Plan
May 2023 6-31
Appendix 6-G: Sample Warning Sign
WARNING
RAW SEWAGE SPILL
AREA CLOSED
NO ENTRY
Contaminated Water
DO NOT come into contact, wade,
swim, or fish in this water.
Keep children and pets
out of the area.
Questions concerning exposure, posting,
and clean up should be directed to:
City of Downey Utilities Division
(562) 904-7202
City of Downey SSMP Chapter 7 Sewer Pipe Blockage
Control Program
May 2023 7-1
Chapter 7 Sewer Pipe Blockage Control Program
This section of the SSMP presents the extent and nature of sewer spills related to Fats, Oils, and Grease (FOG) and the need for a Sewer Pipe Blockage Control Program.
7.1 Regulatory Requirements for the Sewer Pipe Blockage Control Program Element
The collection system agency shall evaluate its service area to determine whether a sewer pipe blockage control program is needed. If the collection system agency determines that a sewer pipe blockage program is not needed, the collection system agency must provide justification for why it is not needed. If FOG is found to be a problem, the collection system agency must prepare and implement a sewer pipe blockage source control program to reduce the amount of these substances discharged to the sanitary sewer system.
The sewer pipe blockage source control program shall include the following as appropriate:
(a) An implementation plan and schedule for a public education and outreach program that promotes proper disposal of pipe-blocking substances;
(b) A plan and schedule for the disposal of pipe-blocking substances generated within the sanitary sewer system service area. This may include a list of acceptable disposal facilities and/or additional facilities needed to adequately dispose of substances generated within a sanitary sewer system service area;
(c) The legal authority to prohibit discharges to the system and identify measures to prevent spills and blockages;
(d) Requirements to install grease removal devices (such as traps or interceptors), design standards for the removal devices, maintenance requirements, best management practices requirements, recordkeeping and reporting requirements;
(e) Authority to inspect grease producing facilities, enforcement authorities, and whether the Enrollee has sufficient staff to inspect and enforce the fats, oils, and grease ordinance; (f) An identification of sanitary sewer system sections subject to fats, oils, and grease blockages and establishment of a cleaning schedule for each section; and (g) Implementation of source control measures for all sources of fats, oils, and grease reaching the sanitary sewer system for each section identified above.
7.2 Nature and Extent of FOG Problem
Between January 1, 2018 and May 5, 2023, which is the current baseline performance period, the City reported one FOG-related sewer spill using the Online Reporting System. The spill represents 94% of the total that occurred during this period (See Appendix 9-A). The City’s average, based on 5.33 years of data, is 0.9 spills/year. The data for the spill is shown on Table 7-1. The total volume of sewage spilled is small.
The majority of the spills occurred in mixed land use areas (commercial and residential) where the source was not identified. There were no FOG-related spills associated with high density residential.
City of Downey SSMP Chapter 7 Sewer Pipe Blockage
Control Program
May 2023 7-2
Table 7-1: Analysis of FOG-Related SSO Data (January 1, 2018 – May 5, 2023) Parameter Value
Total Volume, gallons 5,250
Volume Recovered, gallons 5,250
Volume Entering Storm Drains and/or Surface Waters, gallons 750 Nature of Service Area Residential 33%
High Density Residential 0%
Mixed Commercial & Residential 50%
Commercial/Industrial 17%
The City currently cleans 44 sewer lines (FOG Hotspots) in order to prevent blockages and SSOs due to the deposition of FOG. The City adds sewer lines to its preventive maintenance program following FOG- related blockages or SSO events. The locations of the Hotspots are shown in Figure 7-1. The map shows that the FOG Hotspots are in primarily commercial areas; however, they include sewer lines serving residential and high-density residential areas. A list of the current FOG Hotspots in 2023 is included as Appendix 7-A.
There are approximately 265 commercial FOG sources (restaurants) currently in the City’s sanitary sewer collection system service area. There are likely other FOG sources (e.g. commercial kitchens, caterers, institutional kitchens) that are discharging FOG to the City’s sewer system. Figure 7-2 shows the City’s FOG Hotspots in relationship to commercial sources of FOG. The map demonstrates that there are many areas of the City where frequent preventive maintenance is not required in spite of many commercial sources of FOG. A list of the restaurants in the Stormwater Inspection Program is included as Appendix 7- B.
The results of this analysis indicate that the City’s FOG-related SSOs are minimal in nature (low number and volume entering storm drains) and the majority of them occur in areas with mixed residential and commercial sources. There is no basis, at this time, to support undertaking a commercial FOG source control program nor is there the basis to support undertaking a residential outreach program.
7.3 Public Outreach Program
At applicable FOG-producing food service establishments, the City verifies that grease removal device maintenance records are available and satisfy City Municipal Code Sections 7240.2, 7246, 7272.12, and 7272.14 and Chapter 10 of the California Plumbing Code Sections 1001.0 through 1017.2. This verification is conducted in conjunction with the NPDES inspections that are required at food service establishments.
The inspector also provides sewer blockage prevention educational material and, if needed, a list of grease removal device maintenance companies and haulers. The educational material addresses both FOG control and the prohibition of disposing of rags, wipes, and other products into the City sewer system.
Through the City's sewer maintenance program, City sewer pipes are regularly checked for blockages or build-up from FOG and/or rags and wipes. If there is build-up from FOG and/or rags and wipes in a City sewer pipe, then City staff identifies potential sources from upstream private laterals and investigates them.
If it is determined that a business is causing a sewer pipe blockage, then additional FOG controls are required at this business. Corrective actions at the business may include more frequent grease control device cleaning, grease control device repairs, or the installation of a grease control device (in the event that the business does not have one).
City of Downey SSMP Chapter 7 Sewer Pipe Blockage
Control Program
May 2023 7-3
7.4 Sewer Pipe Blockage Source Control Program
The City’s Sewer Pipe Blockage Control Program consists of providing preventive maintenance for its problematic gravity sewers. The City will continue to collect data related to sewer service calls, sewer cleaning activities, and sewer spills to identify problematic gravity sewer lines. This data will be analyzed and problematic lines will be added to the City’s Hotspot list for more frequent cleaning. The City will re- evaluate the need for a FOG Source Control Program and/or public outreach program during future SSMP updates. Table 7-2 lists the activities that the City will include in its FOG Source Control Program.
Figure 7-1: Location of Sewers Cleaned Frequently to Prevent FOG-Related Spills
City of Downey SSMP Chapter 7 Sewer Pipe Blockage
Control Program
May 2023 7-4
Figure 7-2: Location of Sewers Cleaned Frequently to Prevent FOG-Related SSOs and Relationship to Restaurants
City of Downey SSMP Chapter 7 Sewer Pipe Blockage
Control Program
May 2023 7-5
Table 7-2: Summary of Sewer Pipe Blockage Control Program Activities Focus Activity Status
Commercial
Sources
Optimize sewer cleaning using CMMS. Ongoing
Identify FOG disposal sites and distribute
information to liquid waste haulers.
List available. Will be
distributed by City.
Encourage the use of BMPs in commercial
kitchens.
City will continue to
encourage use of BMPs
during inspections.
High Density
Residential
Sources
Optimize sewer cleaning using CMMS. Ongoing
Repair/replace problem sewers identified during
CCTV inspection program. Ongoing
Prepare and publish outreach materials.
City to prepare materials for
City website and other
publications semi-annually.
Low Density
Residential
Sources
Optimize sewer cleaning using CMMS. Ongoing
Repair/replace problem sewers identified during
CCTV inspection program. Ongoing
Prepare and publish outreach materials.
City to prepare materials for
City website and other
publications semi-annually.
Sewer System
Performance Gather information for next SSMP update. Ongoing FOG Preventative Maintenance
The City’s preventive maintenance program will continue its focus on Hotspots. The City will employ the methods outlined in Chapter 4 – Operations and Maintenance Program to optimize its preventive maintenance activities.
GRD Installation, Design, Maintenance, and Record Keeping There is no indication that grease removal devices (GRDs) would materially improve the performance of the City’s sewer system. Requirements for the installation of GRDs in existing food service establishments are not included in the City’s Sewer Pipe Blockage Source Control Program, but GRDs are required by the City’s Building and Safety Department for all new food service establishments in accordance with California Plumbing Code requirements.
Best Management Practices
Best management practices (BMPs) are activities, practices, facilities, and/or procedures that when implemented to the maximum extent practicable will prevent or reduce pollutants in discharges. Some examples of BMPs are: scraping and dry wiping dishes and cooking utensils prior to washing, general good housekeeping, proper waste handling, and disposal. The City will continue to encourage the use of BMPs during its restaurant inspection program.
7.5 FOG Disposal Facilities
The list of identified FOG disposal sites and liquid waste haulers is included as Appendix 7-C. The City will update the list annually. This information will be distributed during its restaurant inspections. The information will be published on the City’s website.
The number and close proximity of the disposal sites is adequate to handle liquid wastes being removed from current and future grease removal equipment within the City.
City of Downey SSMP Chapter 7 Sewer Pipe Blockage
Control Program
May 2023 7-6
Appendix 7-A: Sewer Lines Included in FOG Hotspot Program ID
Area Location Length (ft)
1 79 Brookpark Rd & Samoline Ave, MH9 to MH3 (584ft) West 584 2 79 W/S Paramount Blvd & S/S of 5Fwy at Off Ramp, MH23 to MH9 (630ft) / MH23 East to MH22 (400ft)
400
3 80 Parrot Ave & Brookpark Rd, MH58 to MH45 (420ft) / MH58 to MH56 (210ft)
630
4 111 Telegraph Rd & Passions Blvd, Service Rd - MH22 to MH34 (308ft) / MH22 to MH26 (270ft) / On Teleg - MH21 to MH22 (55ft)
633
5 111 Telegraph Rd & Hasty Ave, MH17 to MH23 (210ft) South 210 6 109 Gallatin Rd & Lakewood Blvd, MH9 to MH8 (625 ft) / MH14 to MH9 (350ft)
975
7 92 Old River School Rd & Florence Ave, MH40 to MH45 (300ft) 300 8 117
&
107
10304 Paramount Blvd, MH25 to MH55 (545ft)
545
9 140 Downey Sanford Bridge Rd & Florence Ave, Siphon - MH14 North to MH13 (65ft) / MH13 to MH4 (300ft)
365
10 141 Newville Ave & Florence Ave, Siphon - MH29 to MH27 (65ft) 65 11 141
&
140
Pangborn Ave & Florence Ave to County Line, MH11 to MH10 (600ft) / MH11 to MH33 (600ft)
1,200
12 141 10051 Mattock Ave, MH25 to MH18 (305ft) 305
13 137 11016 New St, MH48 East to MH43 (144ft) 144
14 126
&
136
On Myrtle St from 5th St to Firestone Blvd, MH19 East to MH66 (256ft) / Siphon - MH19 to MH# UNKN (50ft)
306
15 126 4th St & Myrtle St, MH25 North to MH19 (271ft) 271 16 136 3rd St & Myrtle St, MH3 North to MH25 (530ft)
17 136 11016 Myrtle St, MH8 North to MH3 (180ft) / MH8 West to MH50 (390ft)
570
18 136 2nd St & Myrtle St, MH16 North to MH8 (200ft) 200 19 136 Behind 8041 Firestone in Alley Enter at Myrtle St, MH19 West to MH31 (390ft) / MH19 North to MH16 (200ft)
590
20 136* Paramount Blvd & Firestone Blvd, MH35 West to MH50 (650ft) / MH35 North to MH27 (350ft)
1,000
21 147
Embassy Suites on Firestone Blvd, MH11 to MH4 (325ft) / MH12 to MH11 (68ft) / MH# to MH12 (13ft) / MH46 to MH# (200ft) / MH44 to MH46 (60ft)
666
22 148* Lakewood Blvd & Firestone Blvd, MH35 West to MH40 (515ft) 515 23 159 Woodruff Ave & Firestone Blvd, MH40 to MH45 (300ft) 300
City of Downey SSMP Chapter 7 Sewer Pipe Blockage
Control Program
May 2023 7-7
ID
Area Location Length (ft)
24 145 7862 Brookmill Rd, MH13 to MH7 (690ft) 690
25 144 Stewart & Gray Rd & Rives Ave, MH15 to MH61 (350ft) / MH15 to MH59 (350ft) / MH14 to MH15 (30ft)
380
26 157 Patton Rd & Cleta St, MH19 to MH6 (284ft) 284
27 155 Paramount Blvd & Alameda St, MH73 to MH57 (680ft) 680 28 165 Rives Ave & Quill Dr, MH45 to MH39 (280ft) / MH46 to MH45 (30ft) 310 29 166 On Alameda St from Paramount Blvd to Downey Ave, MH73 to MH16 (1,565ft)
1,565
30 177 Alley S/O Imperial Hwy E/O Paramount Blvd, MH37 to MH40 (333ft) / MH37 to MH22 (350ft) / Reverse Flush - MH37 to MH49 (275ft) 958
31 191 8039 Adoree St, MH38 North to MH49 (555ft) / MH38 East to MH34 (257ft)
812
32 190 Gardendale St & Paramount Blvd, MH31 to MH12 (660ft) 660 33 206
Downey Ave & Gardendale St, MH40 East to MH# (15ft) / MH# East to 8329 Gardendale St (325ft) / Reverse Flush - MH40 West to MH# (50ft)
390
34 192 Brookshire Ave & Imperial Hwy, MH28 to MH41 (400ft) / MH28 to MH58 (660ft) / MH27 East to MH28 (100ft)
1160
35 192
N/O Imperial Hwy & Verdura Ave, MH14 West to MH15 (300ft) / MH14 South to MH21 (100ft) / Southside Imperial Hwy - MH21 to MH27 (600ft) / MH21 to MH44 (490ft)
1,490
36 168 12102 Marbel Ave, MH9 to MH57 (713ft) S/O Cavel MH9 to MH8 (32ft) / Reverse Flush
745
37 180 Marbel Ave & Alameda St, MH10 to MH8 (668ft) 668 38 195 Imperial Hwy & Bellflower Blvd S/E Corner, MH33 to MH29 (328ft) 328 39 195 9530 Imperial Hwy, MH29 to MH30 (15ft)
40 195 Imperial Hwy & Dunrobin Ave, MH# West to MH21 (600ft) / MH13 West to MH# (50ft) / MH13 to MH10 (275ft)
925
41 196 12310 Woodruff Ave, Service Rd - MH10 East to MH8 (690ft) 690 42 211 Faust Ave & Laurelwood Ln, MH24 to MH16 (300ft) / E/O Faust Ave MH16 to MH11 (350ft)
650
43 148 9021 Firestone Blvd. East of Lakewood Blvd MH 30 to MH29 (175') (Acapulco Restaurant)
175
44 168 Alley Behind 11837 Lakewood Blvd MH 31 to MH 33 - ( 95') 95
* The noted cells represent locations that are maintained overnight due to the heavy traffic on those streets.
City of Downey SSMP Chapter 7 Sewer Pipe Blockage Control Program
May 2023 7-8
Appendix 7-B: Restaurants in Stormwater Inspection Program Street Name Food Service Establishment Address
2nd LA Buns 8237 2nd St
3rd Third Street Coffee 8221 3rd St 101
Apollo Fire Wings 8830 Apollo Way 126
Apollo Running Chicks Fried Chicken 8850 Apollo Way 220 Apollo Lazy Dog Restaurant & Bar 8800 Apollo Way
Apollo Benihana 8801 Apollo Way
Apollo The Olive Restobar 8830 Apollo Way
Apollo Gaucho Grill 8830 Apollo Way 100
Apollo Class 302 Cafe 8855 Apollo Way
Apollo Dickey's Barbecue Pit 8855 Apollo Way
Apollo Flame Broiler 8855 Apollo Way
Apollo Jersey Mike's Sub 8855 Apollo Way
Apollo Pick Up Stix Fresh Asian Flavors 8855 Apollo Way Apollo Bar Louie- The Promenade At Downey 8860 Apollo Way 104 Apollo Chipotle Mexican Grill 8890 Apollo Way
Apollo Mod Pizza 8896 Apollo Way
Apollo Panera Bread 8900 Apollo Way
Apollo 7 Leaves café 8901 Apollo Way
Apollo Five Guys 8901 Apollo Way
Apollo The Noodle Company 8908 Apollo Way
Apollo California Fish Grill 8990 Apollo Way
Bellflower Lucky Guys #2 12801 Bellflower Blvd
Downey OLA Restobar 11040 Downey Ave
Downey Hall Of Fame Market & Deli 10846 Downey Ave
Downey The City Life Deli 11006 Downey Ave
Downey Mambo Grill 11018 Downey Ave
Downey Joseph's Bar & Grill 11032 Downey Ave
Downey Lock And Key Social Drinkery 11033 Downey Ave
Downey Bastards Bbq 11045 Downey Ave
Downey Creamistry 11146 Downey Ave
Firestone Pelican Chicken- Downey 8248 Firestone Blvd
Firestone Taquero Mucho 8260 Firestone Blvd
Firestone Embassy Suites-Downey 8425 Firestone Blvd
Firestone Chipotle Mexican Grill #737/ Atten:
Licensing
8500 Firestone Blvd
Firestone Starbucks 9002 Firestone Blvd
Firestone Taco Bell 7127 Firestone Blvd
Firestone Carl's Jr #18 7200 Firestone Blvd
Firestone Jim's Burgers 7322 Firestone Blvd
Firestone Bob’s Big Boy 7447 Firestone Blvd
Firestone Narai Thai Cuisine 7611 Firestone Blvd
Firestone K-inn Donut 7613 Firestone Blvd
Firestone El Salto Del Fraile 7639 Firestone Blvd
Firestone Stardust Club 7643 Firestone Blvd
Firestone Food Culture La 7665 Firestone Blvd
Firestone Albertsons #6140 7676 Firestone Blvd
Firestone McDonald's 7740 Firestone Blvd
Firestone Mr. Pete's Burgers 7811 Firestone Blvd
Firestone Stater Bros Markets #155 7814 Firestone Blvd
City of Downey SSMP Chapter 7 Sewer Pipe Blockage Control Program
May 2023 7-9
Street Name Food Service Establishment Address
Firestone Papa John's Pizza 7840 Firestone Blvd
Firestone Fatima's Grill 7840 Firestone Blvd 101
Firestone Fonda Maria 7840 Firestone Blvd 104
Firestone Norm's Restaurants, LLC 7955 Firestone Blvd
Firestone Del Taco #857 8028 Firestone Blvd
Firestone Mariscos Choix 8104 Firestone Blvd
Firestone Bionicos La Casitas 8133 Firestone Blvd
Firestone Kellys Tavern 8148 Firestone Blvd
Firestone La Chiva Loca 8157 Firestone Blvd
Firestone Club Db Lounge 8206 Firestone Blvd
Firestone The 20/20 Draft House 8228 Firestone Blvd
Firestone Porto's Bakery Downey 8233 Firestone Blvd
Firestone The Stinkin Crawfish 8240 Firestone Blvd
Firestone Starfish Sushi Downey 8244 Firestone Blvd
Firestone Yogurtland 8250 Firestone Blvd
Firestone Subway 12710 8254 Firestone Blvd
Firestone Waba Grill 8258 Firestone Blvd
Firestone La Chula 8262 Firestone Blvd
Firestone The Hummus Factory 8266 Firestone Blvd
Firestone Protein Spot 8339 Firestone Blvd
Firestone Tacos Don Chente 8339 Firestone Blvd
Firestone San Sai Japanese Grill 8428 Firestone Blvd
Firestone Mimi's Café #11 8455 Firestone Blvd
Firestone Panda Express #1170 8510 Firestone Blvd
Firestone International Coffee & Tea LLC 8550 Firestone Blvd Firestone Boston Market Corp/Boston Mkt 1551 8606 Firestone Blvd Firestone Chick-fil-a @ Downey 8613 Firestone Blvd
Firestone The Habit Burger Grill 8619 Firestone Blvd
Firestone Ralphs Grocery Co #295 8626 Firestone Blvd
Firestone Randy’s Donuts 8721 Firestone Blvd
Firestone Seafood & Tacos Raul 8740 Firestone Blvd
Firestone In-n-Out Burger #112 8767 Firestone Blvd 112
Firestone Acapulco 9021 Firestone Blvd
Firestone Dunkin' Donuts 9070 Firestone Blvd
Firestone The Olive Garden Italian Restaurant #1303 9253 Firestone Blvd Firestone Raising Cane's Chicken Fingers 9265 Firestone Blvd Firestone Cafe-n-stuff 9306 Firestone Blvd
Firestone El Pollo Loco #5592 9341 Firestone Blvd 550
Firestone Dirt Dog 9414 Firestone Blvd
Firestone McDonald's 9475 Firestone Blvd
Firestone Fernando's Restaurant 9484 Firestone Blvd
Firestone Jack In The Box 9511 Firestone Blvd
Firestone Dippity Donuts 9512 Firestone Blvd
Florence Sakana Japanese Restaurant 7934 Florence Ave
Florence Downey Pizza Company 9026 Florence Ave
Florence Myra's Salvadorian Cuisine 7324 Florence Ave
Florence Little Caesars Enterprises #5947 7369 Florence Ave Florence Yum Yum Donuts Franchise 30 7410 Florence Ave
Florence Domino's Pizza #8133 7433 Florence Ave A
Florence T & K Water- Ice Cream 7444 Florence Ave E
Florence Masa Sushi 7808-10 Florence Ave
Florence Bionicos Plus Corp 7818 Florence Ave
City of Downey SSMP Chapter 7 Sewer Pipe Blockage Control Program
May 2023 7-10
Street Name Food Service Establishment Address
Florence Pop's Café Inc 7840 Florence Ave
Florence Guardsmen Lounge 7850 Florence Ave
Florence Tom's Jr. Burgers 7852 Florence Ave
Florence El Taco Of Ca Inc #87 7870 Florence Ave
Florence The Marketplace Grill & Café Inc 7877 Florence Ave Florence KFC 7879 Florence Ave
Florence Black Bear Diner 7900 Florence Ave
Florence Yoshinyoa Beef Bowl 7910 Florence Ave
Florence Subway #10403/laksh Enterprises In 7930 Florence Ave Florence China Wok Express 7932 Florence Ave
Florence Pizza Hut #24948 7936 Florence Ave
Florence Baskin-Robbins #6409 7938 Florence Ave
Florence Los Pollos #3 7940 Florence Ave
Florence Tacos El Gavilan 7947 Florence Ave
Florence Starbucks 7966 Florence Ave
Florence Kyoto Sushi 8009 Florence Ave
Florence Downey Donut 8011 Florence Ave
Florence Los Sombreros 8019 Florence Ave
Florence Las Palmitas Fruit #2 8025 Florence Ave
Gallatin Yoli's Mexican Kitchen 9009 Gallatin Rd
Imperial Domino's Pizza #8230 7840 Imperial Hwy
Imperial Teriyaki Plus 7850 Imperial Hwy
Imperial Jack In The Box #218 7905 Imperial Hwy
Imperial Burger King 13203 7957 Imperial Hwy
Imperial U S A Donuts & Croissants 8009 Imperial Hwy
Imperial Bionicos Don Leo 8027 Imperial Hwy
Imperial Veracruz Restaurant 9085 Imperial Hwy
Imperial The Boys Burgers #10 9090 Imperial Hwy
Imperial Pizza Hut #24836 9111 Imperial Hwy
Imperial Jack In The Box #3186 9501 Imperial Hwy
Imperial Time Out Burger 9841 Imperial Hwy
Imperial Pregio Pizza 8304 Imperial Hwy
Imperial My Home Chinese Restaurant 8716 Imperial Hwy
Imperial Alberto's Mexican Food, Inc 7347 Imperial Hwy
Imperial La Pupuseria Del Pepeto 7939 Imperial Hwy
Imperial Starbucks 7954 Imperial Hwy
Imperial Mr H's Taco 8642 Imperial Hwy
Imperial La Perla Del Mar Inc. 8803 Imperial Hwy
Imperial Zaiqa Grill 8814 Imperial Hwy
Imperial Chick-fil-a 8900 Imperial Hwy
Imperial Carl's Jr #191 9110 Imperial Hwy
Imperial Dong Hua Express Dba Royal Food
Express
9125 Imperial Hwy C
Imperial Subway #42152 9131 Imperial Hwy B
Imperial Stox Restaurant 9518 Imperial Hwy
Imperial Starbucks 9506 E Imperial Hwy
Lakewood Carniceria Los Compadres 10317 Lakewood Blvd
Lakewood Crimson Coward 10405 Lakewood Blvd
Lakewood Honey Greens Cafe 10407 Lakewood Blvd
Lakewood Jack In The Box 10037 Lakewood Blvd
Lakewood Mc Donalds 10207 Lakewood Blvd
Lakewood Mimi's Donuts 10303 Lakewood Blvd
City of Downey SSMP Chapter 7 Sewer Pipe Blockage Control Program
May 2023 7-11
Street Name Food Service Establishment Address
Lakewood Hong Kong Chef Chinese Food 10311 Lakewood Blvd Lakewood Sizzler #53 10315 Lakewood Blvd
Lakewood H Salt Esp. Fish & Chips 10339 Lakewood Blvd
Lakewood Sutha Thai Cuisine 10341 Lakewood Blvd
Lakewood Pieloon Restaurant 10822 Lakewood Blvd
Lakewood La Villa Bakery #2, Et Al 11843 Lakewood Blvd
Lakewood Taqueria Zavala 11907 Lakewood Blvd
Lakewood El Pescador 12002 Lakewood Blvd
Lakewood Philly's Best 12008 Lakewood Blvd
Lakewood Rubio's Restaurant, Inc. 12010 Lakewood Blvd
Lakewood Starbucks Coffee #6672 12016 Lakewood Blvd
Lakewood Jimmy John's 12018 Lakewood Blvd
Lakewood Kaowok Chinese Kitchen 12022 Lakewood Blvd
Lakewood Cold Stone Creamery #444 12024 Lakewood Blvd
Lakewood Ono Hawaiian Bbq 12028 Lakewood Blvd
Lakewood Chili's Bar & Grill 12030 Lakewood Blvd
Lakewood Carino's Italian 12036 Lakewood Blvd
Lakewood Little Caesars #5792 12555 Lakewood Blvd C
Lakewood Tacos Estilo Guadalajara 13121 Lakewood Blvd
Lakewood Food 4 Less #778 13525 Lakewood Blvd
Lakewood Continental Food Mngmnt, Inc / Wendys 14305 Lakewood Blvd Lakewood El Pollo Loco #5365/att: Lic Prmts 14329 Lakewood Blvd 550 Lakewood Starbucks Coffee #10659 8801 Lakewood Blvd
Lakewood Arthur's Coffee Shop #5 8813 Lakewood Blvd
Lakewood Ralphs #173 9200 Lakewood Blvd
Lakewood Flame Broiler 9206 Lakewood Blvd
Lakewood Subway 26401 9228 Lakewood Blvd
Lakewood Maui Sushi & Teriyaki 9230 Lakewood Blvd
Lakewood Louks Greek Baby Donuts 9232 Lakewood Blvd
Lakewood Green Olive Mediterranean 9234 Lakewood Blvd
Lakewood Drinx 9236 Lakewood Blvd
Lakewood Chris & Pitt's Bar-b-q 9243 Lakewood Blvd
Lakewood Mc Donald's Rest Of Ca Inc #2029 9250 Lakewood Blvd Lakewood Poached- Downey 9510 Lakewood Blvd
Lakewood Coffee Bean 9516 Lakewood Blvd
Lakewood Poke 2 Grill 9523 Lakewood Blvd
Lakewood Taco Bell 9551 Lakewood Blvd
Lakewood Golden Corral 9588 Lakewood Blvd
Lakewood Baby Bro's Pizza & Wings 9641 Lakewood Blvd
Lakewood Happy Bagels And Donuts 9926 Lakewood Blvd
New Ichiban Sushi 11020 New St
Old River School Pollos A La Brasa Old River 11408 Old River School Rd Paramount Burger King #4059 10014 Paramount Blvd
Paramount Blizzberry 10033 Paramount Blvd
Paramount Bobaloca 10033 Paramount Blvd
Paramount Tropicana Bakery And Cuban Café 10218 Paramount Blvd Paramount Downey Brewing Co 10924 Paramount Blvd
Paramount La Barca Grill & Cantina 11010 Paramount Blvd Paramount Pina Pizza House 11102 Paramount Blvd
Paramount Boba Indeed 11246 Paramount Blvd
Paramount IHOP 11414 Paramount Blvd
Paramount Pupuseria El Carrisal 11851 Paramount Blvd
City of Downey SSMP Chapter 7 Sewer Pipe Blockage Control Program
May 2023 7-12
Street Name Food Service Establishment Address
Paramount Subway 51110 11858 Paramount Blvd
Paramount Taco Bell #28519 11905 Paramount Blvd
Paramount El Azteca Taqueria 11917 Paramount Blvd
Paramount Emporio Sushi & Mariscos 11949 Paramount Blvd Paramount Shakey's Pizza #50 12030 Paramount Blvd
Paramount Cholito Restaurant Inc 12121 Paramount Blvd
Paramount Nevera Juice Bar 12121 Paramount Blvd
Paramount El 7 Mares Express 12216 Paramount Blvd
Paramount Mc Donalds Rstrnt Of Ca Inc #4587 12256 Paramount Blvd Paramount Alberto's Mexican Food 12620 Paramount Blvd
Paramount El Chilito Restaurant #1 12812 Paramount Blvd Paramount Pasteleria 3 Luceros 12934 Paramount Blvd
Paramount Paramount Tire & Wheel 13049 Paramount Blvd
Paramount Teriyaki J’s 8504 Paramount Blvd
Paramount Toyito's Chicken & Pizza (closed Th) 8510 Paramount Blvd Paramount Granny's Donuts Shop 8534 Paramount Blvd
Paramount Tokyo Gardens 11946 S Paramount Blvd
Paramount Tempo Cantina 12056 S Paramount Blvd
Rosecrans McDonalds 8855 Rosecrans Ave
Rosecrans Louisiana Fried Chicken And Chinese
Food Inc.
8843 Rosecrans Ave C
Rosecrans R & J Southern Home Cooking 8852 Rosecrans Ave Stewart & Gray ABC Donuts 8015 Stewart & Gray
Stewart & Gray Ponce's Bakery #3 7368 Stewart & Gray Rd Stewart & Gray Sunland Donuts 7375 Stewart & Gray Rd
Stewart & Gray Stewart & Grub 7380 Stewart & Gray Rd
Stewart & Gray Old River Restaurant 7395 Stewart & Gray Rd Stewart & Gray Pizza Time 8310 Stewart & Gray Rd
Stewart & Gray Sizzling Thai Kitchen 8330 Stewart & Gray Rd Stonewood Bj's Restaurant & Brew House 121 Stonewood Center Stonewood Sansei 125 Stonewood Center
Stonewood Mediterranean Delight 127 Stonewood Center
Stonewood Tacos Mexico 251 Stonewood Center
Stonewood Prinkipia Coffee & Tea Room 251 Stonewood Center Stonewood Mrs. Field's Cookies/ Bma Technologies,
Inc
321 Stonewood Center
Stonewood Potato Corner 407 Stonewood Center
Stonewood Wetzel's Pretzels 132 Stonewood Mall 303
Stonewood Auntie Anne's Pretzels 251 Stonewood Mall
Stonewood Ice Cream View 319 Stonewood Mall
Stonewood Sbarro The Italian Eatery 440 Stonewood Mall
Stonewood Charleys Philly Steaks 110 Stonewood St
Stonewood Tacos Mexico 111 Stonewood St
Stonewood Mangos 130 Stonewood St
Stonewood Buffalo Wild Wings Bar & Grill #315 193 Stonewood St Stonewood Red Iron Grill Mongolian B.b.q 251 Stonewood St Stonewood Starbucks 251 Stonewood St
Stonewood Tutti Fruitti 251 Stonewood St
Stonewood Cinnabon #437 251 Stonewood St 415
Stonewood Doc Popcorn 251 Stonewood St
Studebaker Nelly’s Mexican Food 108011 Studebaker Rd
Telegraph Tacos Y Pollo Asado El Grullo 8446 Telegraph Rd
City of Downey SSMP Chapter 7 Sewer Pipe Blockage Control Program
May 2023 7-13
Street Name Food Service Establishment Address
Telegraph Jack In The Box 8140 Telegraph Rd
Telegraph Tacos Don Goyo 8502 Telegraph Rd
Telegraph Pepe's Mexican Restaurant 9020 Telegraph Rd
Telegraph Golden Palace Chinese Restaurant 9116 Telegraph Rd Telegraph El Tequilense 9126 Telegraph Rd
Telegraph Tamales Guadalajara, Llc 9134 Telegraph Rd
Telegraph Frantone's Pizza And Spaghetti Villa 9148 Telegraph Rd Telegraph Chris Burgers 9180 Telegraph Rd
Telegraph Taqueria El Atacor #9 9456 Telegraph Rd
Woodruff Mr. Petes Burgers 12050 Woodruff Ave
Woodruff Maria's Grill 13232 Woodruff Ave
City of Downey SSMP Chapter 7 Sewer Pipe Blockage Control Program
May 2023 7-14
Appendix 7-C: Grease Haulers and FOG Disposal Facilities Grease Haulers and FOG Disposal Facilities currently serving the Downey area at the time of this report are shown in the following lists.
Grease Rendering/Drop Off Points for Downey Area
Baker Commodities, Inc. 4020 Bandini Blvd,
Los Angeles, CA (323) 269-6177 8 miles
One More Time 4144 Bandini Blvd,
Los Angeles, CA (800) 624-5504 8 miles
Southwest Processors 4120 Bandini Blvd,
Los Angeles, CA (800) 900-3366 8 miles
Legacy By-Products 4105 Bandini Blvd,
Los Angeles, CA (323) 261-4176 8 miles
Darling International 2626 E 25th St,
Los Angeles, CA (800) 447-3273 12 miles
Orange County Sanitation District,
Plant No. 1
10844 Ellis Ave,
Fountain Valley, CA (714) 593-7428 24 miles
Grease Trap Cleaning/Hauling
Ameriguard Maintenance
Services
Located in Fresno, but serves
the Los Angeles area (800) 347-7876
Baker Commodities 4020 Bandini Blvd,
Los Angeles, CA (323) 269-6177
Darling International Inc 2626 E 25th St,
Los Angeles, CA (800) 447-3273
Mr. Rooter of Commerce 221 W Pomona Blvd,
Monterey Park, CA
(323) 721-1243 or
(626) 280-2454
Rescue Rooter State-wide services (800) 869-6917
SMC Grease Specialist PO Box 1343,
Corona, CA 92878 (951) 788-6042
Triple A Pumping & Jetting Inc. 764 N Cypress,
Orange, CA (714) 628-0900
City of Downey SSMP Chapter 8 System Evaluation, Capacity Assurance and Capital Improvements
May 2023 8-1
Chapter 8 System Evaluation, Capacity Assurance and Capital Improvements
This section of the SSMP presents the City’s System Evaluation, Capacity Assurance and Capital Improvements Plan (SECAP). A still-applicable SECAP plan was prepared in 2009 with the objectives of evaluating the hydraulic capacity of sewer system and identifying any hydraulic deficiencies that contribute or may contribute in the future to sanitary sewer overflows, and to develop a capacity assurance plan to address the identified deficiencies, including short- and long-term capital improvement projects.
8.1 Regulatory Requirements for the System Evaluation and Capacity Assurance Plan Element
The City shall prepare and implement a capital improvement plan that will provide hydraulic capacity of key sanitary sewer system elements for dry weather peak flow conditions, as well as the appropriate design storm or wet weather event. At a minimum, the plan must include:
(a) System Evaluation and Condition Assessment: The Plan must include procedures to:
o Evaluate the sanitary sewer system assets utilizing the best practices and technologies available;
o Identify and justify the amount (percentage) of its system for its condition to be assessed each year;
o Prioritize the condition assessment of system areas that:
o Hold a high level of environmental consequences if vulnerable to collapse, failure, blockage, capacity issues, or other system deficiencies; o Are located in or within the vicinity of surface waters, steep terrain, high groundwater elevations, and environmentally sensitive areas; o Are within the vicinity of a receiving water with a bacterial-related impairment on the most current Clean Water Act section 303(d) List;
o Assess the system conditions using visual observations, video surveillance and/or other comparable system inspection methods;
o Utilize observations/evidence of system conditions that may contribute to exiting of sewage from the system which can reasonably be expected to discharge into a water of the State;
o Maintain documents and recordkeeping of system evaluation and condition assessment inspections and activities; and
o Identify system assets vulnerable to direct and indirect impacts of climate change, including but not limited to: sea level rise; flooding and/or erosion due to increased storm volumes, frequency, and/or intensity; wildfires; and increased power disruptions. (b) Capacity Assessment and Design Criteria: The Plan must include procedures to identify system components that are experiencing or contributing to spills caused by hydraulic deficiency and/or limited capacity, including procedures to identify the appropriate hydraulic capacity of key system elements for:
o Dry-weather peak flow conditions that cause or contributes to spill events;
City of Downey SSMP Chapter 8 System Evaluation, Capacity Assurance and Capital Improvements
May 2023 8-2
o The appropriate design storm(s) or wet weather events that causes or contributes to spill events;
o The capacity of key system components; and
o Identify the major sources that contribute to the peak flows associated with sewer spills.
The capacity assessment must consider:
o Data from existing system condition assessments, system inspections, system audits, spill history, and other available information;
o Capacity of flood-prone systems subject to increased infiltration and inflow, under normal local and regional storm conditions;
o Capacity of systems subject to increased infiltration and inflow due to larger and/or higher- intensity storm events as a result of climate change;
o Increases of erosive forces in canyons and streams near underground and above-ground system components due to larger and/or higher-intensity storm events; o Capacity of major system elements to accommodate dry weather peak flow conditions, and updated design storm and wet weather events; and
o Necessary redundancy in pumping and storage capacities. (c) Prioritization of Corrective Action: The findings of the condition assessments and capacity assessments must be used to prioritize corrective actions. Prioritization must consider the severity of the consequences of potential spills.
(d) Capital Improvement Plan: The capital improvement plan must include the following items:
o Project schedules including completion dates for all portions of the capital improvement program;
o Internal and external project funding sources for each project; and o Joint coordination between operation and maintenance staff, and engineering staff/consultants during planning, design, and construction of capital improvement projects; and o Interagency coordination with other impacted utility agencies.
8.2 System Evaluation and Capacity Assessment
Although there have not been any documented capacity-related sewer overflows in the City of Downey, a comprehensive capacity evaluation using a dynamic hydraulic model was performed to quantify flows and capacities in all major sewers and lift station under current and future flow conditions. The report titled “System Evaluation and Capacity Assurance Plan”, was completed in April of 2009 and is still applicable.
The City’s collection system was modeled using InfoSWMM, a fully dynamic hydraulic model developed by MWH Soft that utilizes the EPA SWMM public domain hydraulic engine. The sewers included in the model consisted of all Downey sewers larger than eight inches in diameter, all of the trunk sewers owned by the Los Angeles County Sanitation Districts (LACSD) that receive significant flows from City sewers, and additional eight-inch sewers serving larger areas, adding up to over 25 percent of the sewers in the City.
The information on the modeled sewers was extracted from the City’s sewer GIS and augmented with as- built drawing research and field measurements as required.
City of Downey SSMP Chapter 8 System Evaluation, Capacity Assurance and Capital Improvements
May 2023 8-3
The City’s service area was divided into 179 tributary areas (median size of 42 acres) for the purposes of estimating existing and build-out sanitary sewer flows. Flows in all tributary areas were estimated using a variety of information sources including census data, general plan land uses, regional growth projections, and water meter billing records. A temporary flow monitoring program consisting of 21 meters was conducted to calibrate the unit flow parameters and verify the modeled flows under dry weather conditions.
Due to a lack of rainfall during the monitoring period, wet weather flows were not measured, and a generalized wet weather flow analysis was performed instead.
The calibrated hydraulic model was used to generate peak flows in each modeled pipe and to evaluate pipe capacities. A pipe was considered to have inadequate capacity if the ratio of flow depth to pipe diameter (d/D) at peak dry weather flow exceeded 75 percent under either existing or build-out conditions. The rationale for applying this d/D ratio is that a pipe flowing that full during the peak hour of a dry weather day may have a relatively high risk of surcharging under peak wet weather flow conditions. Based on the dry weather flow analysis, all of the City’s sewers meet the capacity criteria established in this study under both existing and build-out conditions. No improvement projects are required.
In addition to the dry weather flow analysis, a wet weather flow analysis was performed using “hypothetical” infiltration/inflow hydrographs based on flow monitoring data obtained from other agencies.
For the analysis, hydrographs having a peak flow rate of 2,500 gallons per day per acre were applied to all of the City’s sewered areas, coinciding with the daily peak dry weather flows. This rate of infiltration/inflow was used because it corresponded to a ten-year return period event in other sewer systems similar to Downey’s. The purpose of the wet weather analysis was to identify areas that might be most at risk of SSOs during wet weather and to focus future flow monitoring efforts. The highest risk was identified to be in the upstream reaches of the LACSD trunk sewer along Lakewood Blvd., and in the City sewers that would be affected by backwater from that trunk. Although surcharging would occur during this wet weather event, no actual SSOs were predicted to occur, and none have ever been observed.
8.3 Design Criteria
In addition to the criteria used to evaluate the capacity of existing sewers (as described in the preceding section), the City has adopted criteria for the design of new sewers. The “City of Downey Sanitary Sewer Facilities Design Guidelines, Policies, and Procedures” specifies unit flow rates, peaking factors, hydraulic friction factors, minimum slopes, and maximum allowable depth of flow. For peak dry weather flow conditions, sewers must be designed to flow at depths of no more than 50 percent for eight-inch pipes, up to 75 percent for 15-inch pipes.
8.4 Capacity Enhancement Measures and Corrective Action Based on the results of the capacity evaluation and the lack of any historical capacity-related problems or SSOs, no capital improvements are required. However, the City will periodically monitor wet weather water levels in selected key manholes that were identified as having the greatest risk of surcharging based on the wet weather analysis. Should significant surcharging be observed, additional measures will be undertaken to evaluate the cause of the problem and implement appropriate capacity enhancement and corrective measures.
Capacity driven improvements of the City-owned sewer system such as the extension of a sewer main, upsizing of a main, or installation of an additional parallel sewer main are funded via conditions placed on the development necessitating the capacity improvements. The development would be required to confirm and provide Los Angeles County Sanitation District (LACSD) acceptance of the additional sanitary sewer flows proposed to enter the downstream LACSD trunk sewer prior to the City considering capacity improvements to its own sewer collection system. Where such capacity improvements are agreed to by
City of Downey SSMP Chapter 8 System Evaluation, Capacity Assurance and Capital Improvements
May 2023 8-4
both LACSD and the City, development requirements to design, furnish, and install the necessary sanitary sewer improvements in accordance with Utilities Division standards would be agreed to prior to the development going to the City Planning Commission for approval. Once approved, design and construction of such sanitary sewer improvements to be owned and maintained by the City would be conducted and funded by the development with oversight provided by Utilities Division engineering and operations staff prior to final approval and acceptance by the City.
8.5 Capital Improvement Plan
Sewer system rehabilitation and replacement projects are accounted for in the City’s Five-Year Capital Improvement Program (CIP). The estimated annual expenditures for the City’s Five-Year CIP, which totals $5.7 million for design and construction of sanitary sewer collection system rehabilitation and replacement (in 2023 dollars) projects, are shown by program in Table 8-1.
Each fiscal year the latest available sewer system CCTV data collected from outside contractors and/or Sewer and Stormwater Section operations staff are analyzed. Manhole to manhole pipe segments are first sorted by those with the highest Quick Structural Rating (QSR) which focuses on severity and number of pipe defects having the two highest condition grades. CCTV data for pipe segments with the highest QSR rating are then reviewed by both Utilities Division engineering and sewer/stormwater operations staff to confirm whether such pipe segments and/or specific defects are candidates for repair/rehabilitation or can be reassessed via jetting/cleaning and CCTV at a later date to determine whether the pipe segment and/or defect has further degraded. Those pipe segments and/or defects that require repair/rehabilitation are then grouped according to the type of repair/rehabilitation determined necessary which include: spot repairs, manhole to manhole replacement, and Cured In Place Pipe (CIPP) liners.
Table 8-1: FY 2023/24 – FY 2027/28 Five Year Capital Improvement Program Program
FY
2023/24
FY
2024/25
FY
2025/26
FY
2026/27
FY
2027/28 Totals
Sewer Main Rehabilitation
and Repair Program 1,000,000 900,000 1,000,000 1,000,000 1,000,000 4,900,000 Sewer Video Assessment 400,000 400,000 --- --- --- 800,000 Totals 1,400,000 1,300,000 1,000,000 1,000,000 1,000,000 5,700,000
Plans and specifications are then prepared for the various categories of repair/rehabilitation projects either internally or through procurement of a design consultant with oversight provided by Utilities Division engineering and operations staff. Such projects are then competitively bid throughout each fiscal year and awarded to the lowest responsive and responsible bidder meeting the contractor licensing and experience requirements for each project. Pipe defects considered to be at high risk of impending failure are further considered to be removed from the grouped project and bid separately through an informal bid process to expedite repairs/rehabilitation as/if necessary, depending on the best judgment of staff.
The funds that support the Capital Improvement Program come from the City’s Sewer Fund. The Sewer Fund is an enterprise fund and sewer service charges are periodically reviewed and set based on identified operating and capital improvement needs. Utilities Division staff also look for opportunities to apply for grant funding to help subsidize funding for repairs when available.
Capacity driven improvements of the City-owned sewer system such as the extension of a sewer main, upsizing of a main, or installation of an additional parallel sewer main are funded via conditions placed on
City of Downey SSMP Chapter 8 System Evaluation, Capacity Assurance and Capital Improvements
May 2023 8-5
the development necessitating the capacity improvements. The development would be required to confirm and provide Los Angeles County Sanitation District (LACSD) acceptance of the additional sanitary sewer flows proposed to enter the downstream LACSD trunk sewer prior to the City considering capacity improvements to its own sewer collection system. Where such capacity improvements are agreed to by both LACSD and the City, development requirements to design, furnish, and install the necessary sanitary sewer improvements in accordance with Utilities Division standards would be agreed to prior to the development going the City Planning Commission for approval. Once approved, design and construction of such sanitary sewer improvements to be owned and maintained by the City would be conducted and funded by the development with oversight provided by Utilities Division engineering and operations staff prior to final approval and acceptance by the City.
City of Downey SSMP Chapter 9 Monitoring, Measurement, and Program Modifications
May 2023 9-1
Chapter 9 Monitoring, Measurement, and Program
Modifications
This section of the SSMP presents the City’s approach to Monitoring, Measurement, and Program Modifications.
9.1 Regulatory Requirements for the Monitoring, Measurement, and Program Modifications Element
The requirements for the Monitoring, Measurement, and Program Modifications element of the SSMP are that the City shall:
(a) Maintaining relevant information, including audit findings, to establish and prioritize appropriate Plan activities;
(b) Monitoring the implementation and measuring the effectiveness of each Plan element; (c) Assessing the success of the preventive operation and maintenance activities; (d) Updating Plan procedures and activities, as appropriate, based on results of monitoring and performance evaluations; and
(e) Identifying and illustrating spill trends, including spill frequency, locations and estimated volumes
9.2 Performance Measures
The indicators that the City will use to measure the performance of its sanitary sewer collection system and the effectiveness of its SSMP are:
• Total number of SSOs;
• Number of SSOs for each cause (roots, grease, debris, pipe failure, capacity, lift station failures, and other);
• Portion of sewage contained compared to total volume spilled; • Volume of spilled sewage discharged to surface water; and • Planned to actual performance for preventive maintenance.
9.3 Historical Performance Data
The City has been reporting SSOs and sewer spills using the CIWQS SSO Reporting System since January 2, 2007. The CIWQS SSO Reporting System data, which is included as Appendix 9-A, is used as the City’s historical performance data.
9.4 Baseline Performance
The baseline performance, which shows the performance of the City’s sanitary sewer collection system prior to the implementation of the SSMP, is shown on Table 9-1.
City of Downey SSMP Chapter 9 Monitoring, Measurement, and Program Modifications
May 2023 9-2
Table 9-1: Baseline Performance (January 2, 2007 – April 30, 2009) Performance Indicator Value
SSO Rate, SSOs/100 miles/year 4.1
Primary Cause of SSOs
Roots 0%
Grease 39%
Debris 50%
Pipe Failure 0%
Lift Station Failure 11%
Other 0%
Median SSO Volume, gallons 60
Portion of SSOs ≤ 100 gallons 67%
Portion of SSOs Reported as Category 1 11%
Portion of Spilled Sewage Contained and Recovered 99%
Portion of Spilled Sewage Entering Storm Drains 1%
Data Source: CIWQS
Geospatial and trend analysis is not meaningful at this time due to the limited quantity of data available.
Geospatial and trend analysis may be added in future years as additional data becomes available for analysis.
SSO data from California Region 4 was analyzed for the same time frame in order to provide a basis for comparison of the City’s Baseline Performance data. Table 9-2 presents performance data for agencies having between 150 and 250 miles of sewer mains, and Figure 9-1 presents the SSO Rate data for those agencies. It can be seen from the data that the City’s performance is similar to that of the other agencies, but that the City has a favorable record with respect to spill containment and recovery.
Table 9-2: Baseline Performance of Region 4 Agencies Between 150 and 250 miles of Sewer Mains (January 2, 2007 – April 30, 2009)
Performance Indicator Value
Average SSO Rate, SSOs/100 miles/year 4.0
Median SSO Rate, SSOs/100 miles/year 1.5
Portion of Spilled Sewage Contained and Recovered 68%
Portion of Spilled Sewage Entering Storm Drains 11%
Data Source: CIWQS
Chapter 9 Monitoring, MeasureCity of Downey SSMP ment, and Program Modifications
May 2023 9-3
Current Performance (January 1, 2018 – MTable 9-3: ay 2023) Performance Indicator Value
0.9SSO Rate, SSOs/100 miles/year
Primary Cause of SSOs
0%Roots
20%Grease
60%Debris
20%Pipe Failure
0%Lift Station Failure
0%Other
1,220Median SSO Volume, gallons
20%Portion of SSOs ≤ 100 gallons
14%Portion of SSOs Reported as Category 1
1Portion of Spilled Sewage Contained and Recovered 00%
14%Portion of Spilled Sewage Entering Storm Drains
Data Source: City of Downey
Current Performance of Region 4 AgenciesTable 9-4: Between 150 and 250 miles of Sewer Mains (January 1, 2018 – May 2023)
Performance Indicator Value
0.9Average SSO Rate, SSOs/100 miles/year
0.9Median SSO Rate, SSOs/100 miles/year
Portion of Spilled Sewage Contained and Recovered
14%Portion of Spilled Sewage Entering Storm Drains
Data Source: City of Downey
100%
City of Downey SSMP Chapter 9 Monitoring, Measurement, and Program Modifications
May 2023 9-4
Figure 9-1: SSO Rate of Region 4 Agencies Between 150-250 miles of Sewer Mains (January 2, 2007 – April 30, 2009)
Downey
City of Downey SSMP Chapter 9 Monitoring, Measurement, and Program Modifications
May 2023 9-5
Figure 9-2: SSO Rate of Region 4 Agencies Between 150-250 miles of Sewer Mains (January 1, 2018 – May 2023)
9.5 Performance Monitoring and Program Changes
The City will evaluate the performance of its sanitary sewer collection system at least annually using the performance measures identified in Section 9.2, Performance Measures. The City will update the data and analysis of performance measures at the time of the evaluation.
The City may use other performance measures in its evaluation. The City will prioritize its actions and initiate changes to this SSMP and the related programs based on the results of the evaluation.
A review of the City’s last five (5) years of data indicates there have been five (5) reported spills since 2018. Only one spill in 2018 resulted in a volume of 100 gallons entering the storm drain system and 2019 resulted in a volume of 750 gallons entering the storm drain system due to grease in the sewer system.
These flows were recovered. The low record of spills since 2018 is a good indicator that the City’s implementation of the operation and maintenance program has been successful. The City’s current performance that demonstrates the successful operation and maintenance program implementation is shown in Table 9-3, Table 9-4, and Figure 9-2.
Downey
City of Downey SSMP Chapter 9 Monitoring, Measurement, and Program Modifications
May 2023 9-6
Appendix 9-A: Historical SSO Baseline Data
January 2, 2007 – April 30, 2009
Date
CIWQS
SSO
Event
ID
Street
Number
Street
Name
Estimated
Volume,
gallons
Estimated
Volume
Recovered,
gallons
Volume
Entering
Storm
Drain,
gallons
Primary
Cause
2/23/2007 647408 8335 Gardendale 200 180 20 Grease
4/16/2007 649515 8725 Blandwood 60 60 0 Grease
7/10/2007 654694 12757 Bellflower 80 80 0 Grease
8/6/2007 656727 11864 Julius 8 8 0 Debris
9/1/2007 658201 9724 Blandwood 150 150 0 LS Failure
10/7/2007 706617 9557 Imperial
Hwy 10 10 0 Grease
12/29/2007 710700 7214 Florence 50 50 0 Debris
3/25/2008 716786 10229 Paramount 10 10 0 Grease
4/21/08 717807 12500 Bellflower 75 75 0 Debris
8/29/2008 725671 8727 Firestone 25 20 5 Grease
9/8/2008 728495 8727 Firestone 20 20 0 Debris
9/19/2008 728514 9240 Firestone 25 25 0 Debris
10/28/2008 729327 9507 Pico Vista 35 35 0 LS Failure
12/18/2008 732233 Pritchard 75 75 0 Grease
1/26/2009 734000 8736 Stewart
and Gray 150 150 0 Debris
3/7/2009 736153 8433 Borson 250 250 0 Debris
3/30/2009 736171 8363 Gardendale 150 150 0 Debris
4/7/2009 736155 8003 Brookpark 500 500 0 Debris
Recent Spill Data January 1, 2018 – May 5, 2023
Date
CIWQS
SSO
Event
ID
Street
Number
Street
Name
Estimated
Volume,
gallons
Estimated
Volume
Recovered,
gallons
Volume
Entering
Storm
Drain,
gallons
Primary
Cause
1/10/2018 845652 10645 Studebaker 130 130 0 Pipe
Failure
11/12/2018 854564 8217 Imperial 400 400 100 Debris
1/6/2019 855805 9021 Firestone 5250 5250 750 Grease
3/17/2020 865903 9621 Haledon 10 10 0 Debris
9/17/2021 876533 8601 Florence 325 325 0 Debris
City of Downey SSMP Chapter 10 Internal Audits
May 2023 10-1
Chapter 10 Internal Audits
This section of the SSMP presents the process the City will follow to audit its SSMP and related programs.
10.1 Regulatory Requirements for the SSMP Audits Element The requirements for the SSMP Audits element of the SSMP are that:
The City shall conduct an internal audit of its Sewer System Management Plan, and implementation of its Plan, at a minimum frequency of once every three years. The audit must be conducted for the period after the end of the City’s last required audit period. Within six months after the end of the required 3-year audit period, the Legally Responsible Official or other Authorized Representative shall submit an audit report into the online CIWQS Sanitary Sewer System Database per the requirements in the Sewer System Management Plan Audit Reporting Requirements of Attachment E1 of the General Order.
Audit reports submitted to the CIWQS Sanitary Sewer System Database will be viewable only to Water Boards staff. The internal audit shall be appropriately scaled to the size of the system(s) and the number of spills. The City’s sewer system operators must be involved in completing the audit. At minimum, the audit must:
• Evaluate the implementation and effectiveness of the Enrollee’s Sewer System Management Plan in preventing spills;
• Evaluate the Enrollee’s compliance with the General Order; • Identify Sewer System Management Plan deficiencies in addressing ongoing spills and discharges to waters of the State; and
• Identify necessary modifications to the Sewer System Management Plan to correct deficiencies.
The City shall submit a complete audit report that includes:
Audit findings and recommended corrective actions;
• A statement that sewer system operators’ input on the audit findings has been considered; and • A proposed schedule for the Enrollee to address the identified deficiencies.
10.2 SSMP Audits
The City will audit its SSMP in accordance with the requirements of the Board Order at a minimum of once every three years. The audit will determine whether the SSMP meets the current requirements of the GWDR, whether the SSMP reflects the City’s current practices, and whether the City is following the SSMP.
The audit will be conducted by a team consisting of City Public Works Department Staff. The audit team may also include members from other areas of the City, outside agencies, and/or contractors.
The scope of the audit will cover each of the sections of the SSMP. The SSMP Audit Checklist, based on the requirements in the GWDR, is included as Appendix 10-A.
The results of the audit will be included in an SSMP Audit Report. The SSMP Audit Report will focus on the effectiveness of the SSMP Program, compliance with the GWDR requirements, and identification of any deficiencies in the SSMP. The SSMP Audit Report will identify revisions that may be needed for a more effective program. Information collected as part of Chapter 9 - Monitoring, Measurement, and Program Modifications will be used in preparing the audit. Tables and figures or charts will be used to
City of Downey SSMP Chapter 10 Internal Audits
May 2023 10-2
summarize information about these indicators. The written Audit Report will be completed within 60 days of completion of the audit. Copies of the annual Audit Reports will be maintained by the City for six years.
10.3 SSMP Updates
The City will update its SSMP at least every six years in accordance with the General Order. The compliance date for submitting the updated SSMP is May 2, 2025. This updated SSMP is complying with the SSMP upload requirements to the CIWQS Sanitary Sewer System Database in June 2023. Therefore, it is anticipated that the next SSMP update will be submitted to the State in May 2031.
The City will determine the need to update its SSMP more frequently based on the results of the internal audit and the performance of its sanitary sewer collection system using information from the Monitoring and Measuring Program. In the event that the City decides that an update is warranted, the process to complete the update will be identified at that time. The City will complete the update within one year following identification of the need for the update.
City of Downey SSMP Chapter 10 Internal Audits
May 2023 10-3
Appendix 10-A: SSMP Audit Checklist
Section Title Requirement
SSMP
Current?
Being
Followed?
I Sewer System
Management
Plan Goals and
Introduction
Properly manage, operate and
maintain all portions of the sanitary
sewer system
Reduce, prevent, and mitigate spills
Schedule for updating the SSMP
and for conducting internal audits.
Provide updated maps of the
service area and sanitary sewer
system.
II Organization Designate LRO
Names, emails and phone numbers
for key management personnel
Names, emails and phone numbers
for key administrative personnel
Names, emails and phone numbers
for key maintenance personnel
Chain of communication for
reporting spills and person
responsible for reporting spills to
the SWQCB and other agencies
III Legal Authority Prevent illicit discharges to sanitary sewer system
Require sewers and connections be
properly designed and constructed
Ensure access for inspection,
maintenance, and repairs (includes
public portion of lateral)
Collaborate with storm sewer
agencies to coordinate emergency
spill responses
Require the installation of grease
removal devices
Ensure access for maintenance,
inspection and repairs for service
laterals owned by the City
Enforce violations of the City’s
sewer ordinances
IV O&M Program Maintain up-to-date maps of the
sanitary sewer system
Describe routine preventive
maintenance program
Document completed preventive
maintenance using system such as
work orders
Rehabilitation and replacement plan
that identifies and prioritizes
sanitary sewer system defects
City of Downey SSMP Chapter 10 Internal Audits
May 2023 10-4
Section Title Requirement
SSMP
Current?
Being
Followed?
Provide regular technical training for
City sanitary sewer system staff
including spill response and
electronic CIWQS reporting
Require contractors to provide
training for their workers who work
in the City’s sanitary sewer system
facilities
Maintain equipment inventory
Maintain critical spare part inventory
V Design and
Performance
Provisions
Design criteria and construction
standards for new sanitary sewer
system facilities
Design and construction standards
for repair and rehabilitation of
existing sanitary sewer system
facilities
Procedures for the inspection and
acceptance of new sanitary sewer
system facilities
Procedures for the inspection,
testing and acceptance of repaired
and rehabilitated sanitary sewer
system facilities
VI Spill Emergency
Response Plan
(SERP)
Procedures for the notification of
primary responders
Procedures for the notification of
regulatory agencies
Program to ensure appropriate
response to all spills
Proper documentation and reporting
of all spills in accordance with the
SWRCB General Order.
Procedure to ensure City staff are
aware of and follow the SERP
Procedure to ensure City staff are
trained in the SERP procedures
Procedure to ensure contractor
personnel are aware of and follow
SERP
Procedure to ensure contractor
personnel are trained in the SERP
procedures
Procedures to address emergency
operations such as traffic and crowd
control
Program to contain and prevent the
discharge of sewage to surface
waters or any drainage conveyance
system
City of Downey SSMP Chapter 10 Internal Audits
May 2023 10-5
Section Title Requirement
SSMP
Current?
Being
Followed?
Program to minimize or remediate
the impacts of any spills that occur
Program of accelerated monitoring
to determine the impacts of any
spills that occur
Conduct post spill assessments of
spill response activities.
Annually review and assess
effectiveness of SERP and update
as needed.
VII Sewer Pipe
Blockage Control
Program
Public outreach program that
promotes the proper disposal of
pipe-blocking substances
Plan for the disposal of pipe-
blocking substances generated
within the City’s service area
Demonstrate that the City has
allocated adequate resources for
pipe blockage control
Identification of sanitary sewer
system facilities that have pipe
blockage related problems
Program of preventive maintenance
and installation of grease removal
devices for sanitary sewer system
facilities that have pipe blockage
related problems
VIII System
Evaluation,
Capacity
Assurance and
Capital
Improvements
Identification of elements of the
sanitary sewer system that
experience or contribute to spills
caused by hydraulic deficiencies
and capacity limitations
Established design criteria that
provide adequate capacity
Short term CIP that addressed
known hydraulic deficiencies
Long term CIP that addressed
known hydraulic deficiencies
Procedures that provide for the
analysis, evaluation, and
prioritization of hydraulic
deficiencies
The short- and long-term CIP
programs include schedules for the
correction of each identified
hydraulic deficiency, funding
sources and interagency
coordination
City of Downey SSMP Chapter 10 Internal Audits
May 2023 10-6
Section Title Requirement
SSMP
Current?
Being
Followed?
IX Monitoring,
Measurement,
and Program
Modifications
Maintain relevant information to
establish, evaluate, and prioritize
SSMP activities
Monitor implementation and
effectiveness of the SSMP
Measure, where appropriate,
performance of the elements of the
SSMP
Assess success of the preventive
operation and maintenance
activities
Update SSMP procedures and
activities based on monitoring or
performance
Identify and illustrate spill trends,
frequency, location and estimated
volumes
X Internal Audits Conduct periodic audits every 3
years
Record the results of the audit in a
report
Record the changes made and/or
corrective actions taken
XI Communications
Program
Communicate with the public
regarding the preparation of the
SSMP
Communicate the public regarding
the performance of the SSMP
including spills and discharges
Communicate with tributary or
satellite sewer systems
City of Downey SSMP Chapter 11 Communication Program
May 2023 11-1
Chapter 11 Communication Program
This section of the SSMP presents the process involved in communicating with interested members of the public regarding the development, implementation, and performance of this plan. This Communication Program also addresses communication with the City of Pico Rivera whose sewer system lies north of Downey.
The Plan must include procedures for the City to communicate with:
• The public for:
o Spills and discharges resulting in closures of public areas, or that enter a source of drinking water; and
o The development, implementation, and update of its Plan, including opportunities for public input to Plan implementation and updates.
• Owners/operators of systems that connect into the City’s system, including satellite systems, for:
o System operation, maintenance, and capital improvement-related activities.
11.1 Regulatory Requirements for the Communication Plan Element The City shall communicate on a regular basis with the public on the development, implementation, and performance of its SSMP. The communication system shall provide the public the opportunity to provide input to the City as the program is developed and implemented.
The City shall also create a plan of communication with systems that are tributary and/or satellite to the City’s sanitary sewer collection system.
11.2 Communication Plan
The City’s Spill Emergency Response Plan (SERP) provides a detailed list of the reporting procedures and a list of agencies to be contacted in the event of a sewer spill event.
During preparation of the original SSMP, the City posted a notice on its City of Downey and City of Downey Department of Public Works websites to inform interested members of the public to review and comment on the SSMP. Notice of Public Hearing to adopt the SSMP was provided on the City of Downey and City of Downey Department of Public Works websites. The Public Hearing was subsequently held and all remarks and suggestions brought to the attention of the City before the Public Hearing were presented to the City Council as part of the administrative record. The SSMP was adopted by City Council following the Public Hearing. Since this 2023 SSMP is an update to the previous SSMP, the plan will be recertified and sent to the City Council for approval.
11.3 Communication of Sanitary Sewer System Performance Outreach material related to FOG control and sewer blockages is handed out during restaurant inspections and uploaded to the City’s website. As presented in Figure 11-1, the City has a poster that discusses best practices for preventing sewer blockages and sewer spills.
The posting on the City’s websites also includes the following notice:
Sanitary sewer system performance data for the prior Fiscal Year is available for review at the Public Works Department Utilities Yard located at 9252 Stewart and Gray Road, Downey, CA
City of Downey SSMP Chapter 11 Communication Program
May 2023 11-2
90241. Interested parties can contact Matt Robertson, Utilities Superintendent, at (562)904- 7202 or [email protected] for additional information.
11.4 Communication with Tributary/Satellite Sanitary Sewer Systems The City of Pico Rivera lies just north of the City of Downey. A small portion of the wastewater generated within the City of Pico Rivera and City of Downey is conveyed by Pico Rivera’s sanitary sewer system across the City boundary to a sewer line draining westerly on Telegraph Road. The sewer line in question is maintained by Los Angeles County Department of Public Works Sewer Maintenance, is approximately 1,510 feet long, and connects to a trunk sewer owned and operated by LACSD. Ownership of the 1,510 feet of sewer main is presently unknown.
Given the unknown ownership status there are presently no plans to prepare an agreement for providing sewer capacity. However, the City has been in communication with Pico Rivera regarding resolution of ownership status.
City of Downey SSMP Chapter 11 Communication Program
May 2023 11-3
Figure 11-1: Best Practices for Reducing FOG Sewer Blockages and Spills
Appendix
A System Evaluation and Capacity Assurance Plan
B Sewer Rehabilitation and Replacement Plan
C Sanitary Sewer Facilities Design Guidelines, Policies, and Procedures D Sampling Procedures (SOP No. SSO01)
E Sewer Maintenance (SOP No. SM01)
F Spill Emergency Response Plan (SOP No. SER01)
G Water Quality Monitoring Program (SOP No. WQM01)
Appendix
A System Evaluation and Capacity Assurance Plan
City of Downey System Evaluation
and Capacity Assurance Plan
Prepared by:
Wat er andEnvironment
May 2009
May 2009
Chapter 1 Executive Summary ............................................................................................1-1 Table of Contents
Chapter 2 Introduction .........................................................................................................2-1
2.1 Background and Study Objectives .........................................................................2-1
2.2 Study Area.............................................................................................................2-1
2.3 Existing Collection System ....................................................................................2-1 Chapter 3 Collection System Model Development .............................................................3-1
3.1 Modeling Methodology...........................................................................................3-1
3.2 Modeled Sewers and Subcatchments ....................................................................3-2
3.3 Sewer Database Development ..............................................................................3-2 Chapter 4 Existing and Future Wastewater Flows..............................................................4-1
4.1 Data Sources .........................................................................................................4-1
4.2 Temporary Flow Monitoring ...................................................................................4-3
4.3 Existing (2006) Dry Weather Flow .........................................................................4-6
4.3.1 Residential Flow ....................................................................................................4-6
4.3.2 Non-Residential Flow ............................................................................................4-7
4.3.3 Major Dischargers .................................................................................................4-8
4.3.4 City of Pico Rivera .................................................................................................4-8
4.4 Buildout Dry Weather Flow ....................................................................................4-8
4.4.1 Residential Flow .................................................................................................. 4-10
4.4.2 Non-Residential Flows ......................................................................................... 4-10
4.4.3 Major Dischargers ............................................................................................... 4-11
4.4.4 City of Pico Rivera ............................................................................................... 4-11
4.5 Dry Weather Flow Summary ................................................................................ 4-11
4.6 Wet Weather Flow Assumptions .......................................................................... 4-12 Chapter 5 Sewer System Capacity Analysis .......................................................................5-1
5.1 Capacity Analysis Criteria ......................................................................................5-1
5.2 Dry Weather Flow Analysis ....................................................................................5-1
5.3 Wet Weather Flow Analysis ...................................................................................5-4 Chapter 6 Recommended Capacity Assurance Plan ..........................................................6-1
Table 3-1: Modeled System Characteristics 3-2
List of Tables
Table 4-1: Data Sources 4-2
Table 4-2: Temporary Flow Meters 4-4
Table 4-3: City of Downey Dry Weather Flow Summary 4-11 Table 6-1: Recommended Surcharge Monitoring Locations 6-2
Figure 2-1: Study Area 2-2
List of Figures
Figure 2-2: Wastewater Collection System 2-3
Figure 3-1: Model Network 3-3
Figure 4-1: Temporary Flow Meter Locations 4-5
Figure 4-2: Calibrated Diurnal Profiles 4-7
Figure 4-3: Metered Monthly Water Use (2005-2006) 4-8
Figure 4-4: General Plan Land Use Designations 4-9
Figure 4-5: Typical Subcatchment Wet Weather Hydrograph 4-13 Figure 5-1: 2006 DWF Maximum Depth-to-Diameter Ratio 5-2 Figure 5-2: 2030 DWF Maximum Depth-to-Diameter Ratio 5-3
May 2009
Figure 5-3: Hypothetical 2006 WWF - Maximum Depth-to-Diameter Ratio 5-5 Figure 5-4: Hypothetical 2030 WWF - Maximum Depth-to-Diameter Ratio 5-6 Figure 6-1: Recommended Surcharge Monitoring Locations 6-3
Appendix A - Dry Weather Model Calibration
Appendices
May 2009
cap
List of Abbreviations
Capita (household)
CSDLAC County Sanitation Districts of Los Angeles County (also LACSD) d/D Depth over Diameter
DWF Dry Weather Flow
gpad Gallons per day per acre
gpd Gallons per day
gpm Gallons per minute
GIS Geographic Information System
I/I Inflow/Infiltration
LMDR Low-Medium Density Residential
MDR Medium Density Residential
mgd Million gallons per day
OCSD Orange County Sanitation District
SCAG Southern California Association of Governments
SFR Single Family Residential
SSO Sanitary Sewer Overflow
SSMP Sewer System Management Plan
SUD Second Unit Development
TS Trunk Sewer
WWF Wet Weather Flow
City of Downey System Evaluation and Capacity Assurance Plan Chapter 1 Executive Summary
May 2009 1-1
Chapter 1 Executive Summary
In November 2006, the City of Downey (City) retained RMC Water and Environment (RMC) to assist City staff in the preparation of a Sewer System Management Plan (SSMP). One element of the SSMP is the System Evaluation and Capacity Assurance Plan (SECAP). The two main objectives of the SECAP are to:
• Evaluate the hydraulic capacity of sewer system and identify any hydraulic deficiencies that contribute or may contribute in the future to sanitary sewer overflows (SSOs). • Develop a capacity assurance plan to address the identified deficiencies, including short- and long-term capital improvement projects.
Although there have been no documented capacity-related SSOs in Downey, a comprehensive capacity evaluation using a dynamic hydraulic model was performed to quantify flows and capacities in all major sewers under current and future flow conditions.
The City’s collection system was modeled using InfoSWMM, a fully dynamic hydraulic model developed by MWH Soft that utilizes the EPA SWMM version 5 public domain hydraulic engine. Unlike static or pseudo-dynamic models, InfoSWMM realistically represents the effects of surcharging, storage and backwater on flows in the system over time. The sewers included in the model were jointly selected by City staff and RMC, and consisted of all Downey sewers larger than 8 inches in diameter, all of the trunk sewers owned by the County Sanitation Districts of Los Angeles County (CSDLAC) that receive significant flows from City sewers, and additional 8-inch sewers serving larger areas. The total modeled system includes over 25 percent of the sewers in the City. The information on the modeled sewers was extracted from the City’s sewer GIS and augmented with record drawing research and field measurements as required.
The City’s service area was divided into 181 subcatchments (median size of 42 acres) for the purposes of estimating existing and buildout wastewater flows. Flows in all subcatchments were estimated using a variety of information sources including census data, general plan land uses, regional growth projections, water meter billing records, and record drawings. A temporary flow monitoring program consisting of 21 meters was conducted to calibrate the unit flow parameters and verify the modeled flows under dry weather conditions. Due to a lack of rainfall during the monitoring period, wet weather flows were not measured, and a generalized wet weather flow analysis was performed instead.
The calibrated hydraulic model was used to generate peak flows in each modeled pipe and to identify capacity deficiencies. Based on the dry weather flow analysis, all of the City’s modeled sewers meet the capacity criteria established in this study under both existing and buildout conditions. No capacity-driven improvement projects are required. The generalized wet weather analysis focused on identifying those sewers that may be most at risk of overflowing under a hypothetical 10-year storm event. No modeled pipes were identified as being at risk of overflow during the hypothetical 10-year storm event.
A staged level and flow monitoring program is recommended, focusing on the sewers with the highest risk of SSOs based on the modeling analysis. In addition, the City should continue to maintain and refine the model over time and utilize it to assess impacts of future developments if they deviate significantly from the current projections.
City of Downey System Evaluation and Capacity Assurance Plan Chapter 2 Introduction
May 2009 2-1
Chapter 2 Introduction
This introductory chapter provides background information on the scope and objectives of this study, the City’s sewer system and service area, and the contents and organization of this report.
2.1 Background and Study Objectives
In November 2006, the City of Downey (City) retained RMC Water and Environment (RMC) to assist City staff in the preparation of a Sewer System Management Plan (SSMP). One element of the SSMP is the System Evaluation and Capacity Assurance Plan (SECAP). The two main objectives of the SECAP are to:
• Evaluate the hydraulic capacity of sewer system and identify any hydraulic deficiencies that contribute or may contribute in the future to sanitary sewer overflows (SSOs). • Develop a capacity assurance plan to address the identified deficiencies, including short- and long-term capital improvement projects.
Although there have been no documented capacity-related SSOs in Downey, a comprehensive capacity evaluation using a dynamic hydraulic model was performed to quantify flows and capacities in all major sewers under current and future flow conditions.
2.2 Study Area
The study area for this Master Plan consists of the City of Downey, which is an urbanized community located approximately 12 miles southeast of downtown Los Angeles. The City is bounded by the San Gabriel River to the east, Telegraph Road to the north, the Rio Hondo to the west, and Gardendale Street and Foster Road to the south. There is a small triangular portion of the City to the east of the San Gabriel River bounded by the I-5 Freeway to the northeast and Cecelia Avenue to the south. The boundaries of the City are shown in Figure 2-1.
The City contains approximately 12.8 square miles of land, and its topography is relatively level. Its elevations range from approximately 85 feet above sea level in the southern portion to 140 feet in the northern-most portion. Excluding open space, approximately 75 percent of the City’s land is residential.
The estimated population was 112,985 in 2006, which is the year that existing flows were based on.
2.3 Existing Collection System
Figure 2-2 shows the City’s wastewater collection system. As shown in the figure, the City’s sewer mains discharge into trunk sewers owned and operated by the County Sanitation Districts of Los Angeles County (CSDLAC or District). Some of the District trunk sewers in the City also convey wastewater from upstream cities, and some of the trunk sewers simply pass through the City without collecting any wastewater generated in Downey. The wastewater from Downey is conveyed to and treated at one of two CSDLAC facilities: the Los Coyotes Water Reclamation Plant located in the City of Cerritos, and the Joint Water Pollution Control Plant located in the City of Carson. A portion of the sewer system in the City of Pico Rivera drains Pico Rivera and Downey flows to a 1,510-foot sewer that runs along the border between the two cities before entering a District trunk sewer. Ownership of this 1,510 foot section of sewer is presently unknown.
The City’s collection system is comprised of approximately 190 miles of sewer mains, 4,300 manholes, two small lift stations, and other associated facilities. The City’s gravity sewers are all composed of vitrified clay pipe ranging from 6 to 21 inches in diameter, over 90 percent of which are 8 inches. The majority of the sewer mains were installed between 1945 and 1955, with the oldest sewers dating back to 1927. The laterals that connect customer structures to the City’s mains are privately owned and maintained and are excluded from this evaluation.
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City of DowneySystem Evaluation and Capacity Assurance Plan Figure 2-1: Study Area
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Downey City Limits
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City of DowneySystem Evaluation and Capacity Assurance Plan Figure 2-2: Wastewater Collection System
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CSDLAC Trunks
Downey Sewers
Major Streets
Downey City Limits
City of Downey System Evaluation and Capacity Assurance Plan Chapter 3 Collection System Model Development
May 2009 3-1
Chapter 3 Collection System Model Development
A dynamic hydraulic model of the City’s service area and major sewers was the primary analytical tool used in this study to estimate flows and assess sewer capacities. This chapter describes the modeling software and methodologies. Topics include the selection of the major sewers included in the model, the development of the required data on those major sewers from the City’s GIS, and the delineation of sewer subcatchments and load points to the modeled sewers.
3.1 Modeling Methodology
The City of Downey collection system was modeled using InfoSWMM, a fully dynamic hydraulic model developed by MWH Soft that utilizes the EPA SWMM version 5 public domain hydraulic engine. Unlike static or pseudo-dynamic models, InfoSWMM realistically represents the effects of surcharging, storage and backwater on flows in the system over time.
The modeled network consists of links and nodes, which represent, respectively, the pipes and manholes in the modeled system. The service area is divided into subcatchments, each of which is tributary to a node on the modeled system. Subcatchment parameters define flows entering the collection system, including population-driven sanitary flow, non-residential water meter flows, and infiltration/inflow (I/I).
Several steps are involved in the model-building and application process in order to ensure that the model will accurately predict existing and future flows and capacity limitations. This methodology is summarized below. Additional details are presented in subsequent sections and chapters of this report. • Select the major sewers to be included in the model.
• Extract relevant manhole and pipe data on modeled sewers from the City’s GIS database, including spatial coordinates, manhole identifiers and rim elevations, pipe invert elevations, diameters, and lengths.
• Import sewer data to the modeling software and validate the data (i.e., check for incomplete or erroneous data values). Make corrections based on record drawing research and/or field inspections.
• Divide the service area into subcatchments, consisting of areas of unmodeled pipes tributary to modeled manholes.
• Compile information on land uses and population for both existing and buildout conditions using information from the U.S. Census, the Southern California Council of Governments (SCAG), the City Planning Department, California Department of Finance, and other sources. Also compile water billing data for non-residential customers and geocode them to subcatchments based on addresses.
• Select representative dry weather days from the temporary flow monitoring periods and load the flow data from each of the temporary flow monitors for those days into the model for comparison to modeled flows. Calibrate the residential per-capita flow rates and 24-hour diurnal flow profiles to match the observed flow volumes and peaks at each monitor. • Due to lack of rainfall during the temporary flow monitoring period, develop wet weather flow hydrographs based on analysis of wet weather modeling data obtained from the Orange County Sanitation District (OCSD).
• Determine appropriate dry and wet weather design flow and hydraulic capacity analysis criteria. • Run the calibrated model for existing (Year 2006) and buildout scenarios under design dry and wet weather flow conditions. Quantify capacity utilization in each pipe segment and identify and prioritize sewer reaches having capacity deficiencies.
• As necessary, develop capacity assurance projects to address identified deficiencies.
City of Downey System Evaluation and Capacity Assurance Plan Chapter 3 Collection System Model Development
May 2009 3-2
3.2 Modeled Sewers and Subcatchments
The sewers to be included in the model were jointly selected by City staff and RMC. The initial selection of pipes to include in the model consisted of all Downey sewers larger than 8 inches in diameter, and all District trunk sewers that receive significant flows from City sewers (some trunk sewers simply pass through the City and were therefore not modeled). Additional 8-inch sewers were added as needed to reduce the size of tributary subcatchments (the target was to keep subcatchment size below 50 acres) and to ensure that at least 25 percent of the sewers (including both City and modeled District trunks) were included in the model.
Sewer subcatchments were delineated based on the routing of sewers to the modeled sewer system. Each subcatchment was assigned a load point manhole on a modeled sewer. In cases where there is actually more than one load point (each with a very small tributary area that is part of the subcatchment), a single load point was assumed that best represents where the majority of the flow is discharged to the modeled sewer. The final modeled system and sewer subcatchments are shown in Figure 3-1. Table 3-1 lists basic characteristics of the modeled system.
Table 3-1: Modeled System Characteristics
Model Characteristic Value or Range
Total Length of Modeled Sewers 55 miles
Length of Modeled City Sewers 41 miles
Length of Modeled District Trunks 14 miles
Range of Pipe Diameters (City) 8 to 21-inch
Range of Pipe Diameters (District) 12 to 84-inch
Number of Manholes 1180
Number of Subcatchments 179
Size of Subcatchments
3 to 200 acres; median size of 42
acres
3.3 Sewer Database Development
The City provided a GIS file of the sewer system in ArcGIS format, from which the relevant data on the modeled sewers were extracted, including spatial coordinates, manhole identifiers and rim elevations, and pipe invert elevations, diameters, and lengths. The extracted data were imported to the modeling software and validated using a series of automated checks and inspection of plotted pipe profiles. These checks were required to ensure that the system is properly connected (upstream and downstream manholes are correct) and that there is no missing data. Downstream pipes smaller than upstream pipes, downstream pipes higher than upstream pipes, pipe crowns above ground level (may occur where data on ground elevation is missing), and pipe reverse slope were additional potential errors detected during data validation. When these potential errors were found, data were checked against plans and corrected as needed. In some cases, field inspections by City staff were required, particularly to verify interconnections where pipes cross and where there are two outlet pipes from a single manhole.
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City of DowneySystem Evaluation and Capacity Assurance Plan Figure 3-1: Model Network
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City of Downey System Evaluation and Capacity Assurance Plan Chapter 4 Existing and Future Wastewater Flows
May 2009 4-1
Chapter 4 Existing and Future Wastewater Flows
This chapter describes the development of the existing (2006) and future (buildout) wastewater flow estimates. The flow estimates were based on the best available information on current and projected population and land use assumptions obtained from planning documents, metered water consumption records, and monitored wastewater flows. The flow monitoring data included temporary flow monitoring performed as part of this study and from flow metering data obtained from CSDLAC. Due to lack of rainfall during the temporary flow monitoring period, design wet weather flow parameters were developed based on flow monitoring data obtained from the Orange County Sanitation District.
4.1 Data Sources
A number of data sources were used in the process of estimating wastewater flows. These sources provided information on existing and projected population, dwelling units, employment, and land use, as well as metered water consumption and monitored wastewater flows. Table 4-1 provides brief descriptions of these data sources and how they were used in this study.
City of Downey System Evaluation and Capacity Assurance Plan Chapter 4 Existing and Future Wastewater Flows
May 2009 4-2
Table 4-1: Data Sources
Data Source Description
Geographic
Level Use
2000 Census U.S. Census
Bureau
Year 2000 Population
Counts
Census Block Establish population in 2000
Estimate household size by land use
category and block
Zoning Downey
Planning
Department
Existing land use (40
codes)
Generalized
Parcels
Determine existing land use if not
available in tax assessor’s database
Tax
Assessor’s
Database
Downey
Planning
Department
Database containing
existing #DUs and
detailed land use code
(275 codes)
Parcels Determine #DUs/parcel
Determine existing land use
Locate vacant properties
Vision 2025
General Plan
Downey
Planning
Department
Detailed planning
document describing
planned land use (13
codes), population
density, development,
redevelopment for
buildout
Parcels Assign parcels to planned land use for
calculation of buildout population and
commercial flow
Define #DU/acre for residential land
use types
Locate Second Unit Development
Areas
Downey
Landing
Specific Plan
and EIR
Downey
Planning
Department
Planned redevelopment
of former Downey
Landing area
Parcels Determine planned land use and
wastewater production of large
redevelopment area (not in General
Plan)
Water Billing
Data
Downey
Public Works
Department
Bimonthly water billing
data for all water
customers
Parcels Calculate gpd/acre for commercial
land use types (apply to buildout
scenario)
Distribute existing commercial flow to
parcels using street address
Temporary
Flow
Monitoring
Data
E2 and
CSDLAC
Downey flow data from
early 2007 (E2) and
2005-2007 (CSDLAC)
21 sites (E2)
26 sites
(CSDLAC)
Measure total flow entering Downey
system from Pico Rivera
Establish existing unit flows per capita
and diurnal flow patterns (calibration)
OCSD Flow
Monitoring
Data
OCSD and
ADS
OCSD flow data from wet
winter of 2004-2005
150 sites Establish representative
infiltration/inflow criteria (due to lack of
wet weather in 2007)
CSDLAC
Industrial
Waste
Permits
CSDLAC Wastewater production of
industrial dischargers
N/A Characterize Coca-Cola plant
wastewater flows
2030 Forecast Southern
California
Council of
Governments
(SCAG)
Population, household
count, and employment
projections by 5-yr
increments 2000-2030
City Establish growth of population and
employment by 2030 for Downey and
Pico Rivera
2006
Population
and
Employment
State
Department
of Finance
Population, household
count, and employment
figures for 2006
City Validate estimate of existing house
count and population from tax
assessor’s database and census
Establish existing population for Pico
Rivera
City of Downey System Evaluation and Capacity Assurance Plan Chapter 4 Existing and Future Wastewater Flows
May 2009 4-3
4.2 Temporary Flow Monitoring
A temporary flow monitoring program was conducted as part of this study by E2 Consulting Engineers, Inc. under subcontract to RMC. A total of 21 depth-velocity flow monitors were installed at strategic locations in both City and District trunk sewers to calibrate the flows generated by the hydraulic model.
The results of the flow monitoring program were used to determine City-specific unit flow rates (e.g., gallons per day per capita) and diurnal flow patterns for residential and non-residential land uses. The original intent was to also obtain flow data during wet weather events, but there was no significant rainfall during the monitoring period. Instead, wet weather flows were estimated by use of data obtained from the Orange County Sanitation District (described later in this chapter).
Table 4-2 documents the locations of the flow meters and the characteristics of pipes and tributary areas.
The meters were located so as to isolate specific land use types, measure flows in major sewers, verify flows downstream of flow splits, and measure flows from other cities in CSDLAC trunk sewers at the point where they enter Downey. Figure 4-1 shows the location of the flow meters. The meters were operational for a six-week period, with meters installed between February 2 and 6, 2007 and removed between March 16 and 20, 2007.
Further discussion of the use of the temporary flow monitoring data and additional monitoring data obtained from CSDLAC to calibrate the hydraulic model is presented later in this chapter and in Appendix A.
City of Downey System Evaluation and Capacity Assurance Plan Chapter 4 Existing and Future Wastewater Flows
May 2009 4-4
Table 4-2: Temporary Flow Meters
Meter
Name Manhole ID Land Use
Diam.
(inches) Location Reason for Including in Study
D1 SMN1707003 SFR5000c 10
Quill, Old River
School Road
Isolates SFR5000 land use.
Monitors Quill Dr. TS
D3A SMN0716002
SFR5000,
SFR7500d 10
Paramount,
Gallatin
Monitors city-owned portion of
Old River School Rd. TS
D4 SMN1954003 Mixed Use 15
Old River
School Rd,
Burns
Monitors Downey Ave. TS
D6 SMN2514002
SFR5000,
2FAMRESf 10
Paramount,
Priscilla
Partially isolates 2FAMRES
land use. Monitors Parrot Ave.
TS
D7 SMN1071003 SFR10000e 10
Florence,
Sideview
Isolates SFR10000 land use.
Monitors East Compton Blvd.
TS
D8 SMN0798002
SFR7500
MFRg, COMM 10
Lexington,
Gallatin Monitors Gallatin Rd. TS
D9 SMN0025003
SFR5000,
COMM, MFR 12
Imperial Hwy,
Rose Monitors Imperial Hwy TS
D10 SMN2505001 Mixed Use 15
Alameda,
Blodgett Monitors Alameda St. TS
D11 SMN0928007 MFR, IND 12
Bellflower,
Borson Monitors E. Bellflower Blvd. TS
D12 NAb Commercial 12
Bellflower,
Borson
Isolates commercial land use.
Monitors W. Bellflower Blvd. TS
C1 M23275a Mixed Use 27
Nada St,
Pernell Ave
Meters C1 Through C5, located
at the downstream end of major
trunks, monitor 89% of total
Downey flow.
C2 SMN0105004 Mixed Use 15
Devenir Ave,
Barlin Ave
C3 SMN017006 Mixed Use 21 Clark, Hoback
C4 SMN2089001 Mixed Use 27
Bellflower,
Muroc
C5 SMN2096002 Mixed Use 24
Cornuta,
Adoree
C6 SMN2047004 Mixed Use 15
Hopeland,
Florence
Meters C6 and C7 monitor flow
downstream of a major flow
split on the Old River School
TS. C7 SMN0355005 Mixed Use 27
Rives,
Irwingrove
C8 SMN0174003 Mixed Use 18
Firestone,
Lakewood
Monitors flow downstream of a
major flow split on Downey-
Bellflower TS.
C9 SMN0838002 Mixed Use 15
Nance,
Pangborn
Monitors flow on East Compton
Blvd Extension TS.
C10 SMN2050003 --- 15
Telegraph,
Lowman
Quantify flow entering Downey
at upstream end of system.
C11 SMN0177004 --- 18
Serapis,
Claymore
Quantify flow entering Downey
at upstream end of system.
a LACSD manhole ID. Downey Manhole ID not available.
b New sewer –Manhole IDs have not yed been defined
c SFR5000 = Single Family Residential, 5000 sq. ft. lot (high density) d SFR7500 = Single Family Residential, 7500 sq. ft. lot (medium density) e SFR10000 = Single Family Residential, 10000 sq. ft. lot (low density) f 2FAMRES = Two family Residential
g MFR = Multi Family Residential
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City of DowneySystem Evaluation and Capacity Assurance Plan Figure 4-1: Temporary Flow Meter Locations (Feb-Mar 2007) ´
Legend
#Meter Site
Model Network
Streets
Downey City Limits
City of Downey System Evaluation and Capacity Assurance Plan Chapter 4 Existing and Future Wastewater Flows
May 2009 4-6
4.3 Existing (2006) Dry Weather Flow
Both residential and non-residential dry weather wastewater flows were estimated using information compiled at the parcel level (23,500 parcels) and then aggregated into 179 subcatchents (load points in the hydraulic model). Parcels were determined to be residential or non-residential based on either the tax assessor’s land use code or from zoning data. Details of the procedure used to estimate and distribute the existing dry weather flows for residential flows, non-residential flows, major dischargers, and the City of Pico Rivera are described below.
4.3.1 Residential Flow
Existing residential dry weather flows were computed by multiplying the estimated 2006 population by per capita unit flow rates. The population estimates were made at the parcel level, based on Year 2000 census data, updated estimates by the State Department of Finance and SCAG, and the latest information on developed parcels from the tax assessor’s database.
The process consisted of the following steps:
• The Year 2000 census counts for population (cap) and dwelling units (DU) were used to establish the household size (cap/DU) in each of 932 census blocks. While the household sizes vary considerably by census block, the city-wide average was 3.15 cap/DU in 2000. • The SCAG city-wide population and household estimates for 2005 indicate that most of the increase in population since 2000 is attributable to an increase in average household size, rather than an increase in number of households (number of households increased by only 0.9 percent, while population increased by 4.5 percent). The State Department of Finance population estimate for 2006 confirms this increase in household size. The increase in household size from 2000 to 2006 was approximately 4 percent, up to a current city-wide average of 3.28 cap/DU. • The Year 2000 household sizes in each census block were increased by 4 percent to reflect the larger household sizes in 2006, while retaining the spatial variation in household size by census block.
• The number of dwelling units on each residential parcel in 2006 was extracted from the tax assessor’s database. This number was multiplied by the adjusted household size (based on the census block that parcel is in) to compute the 2006 population in each parcel. Residential parcels with zero dwelling units per parcel were assumed to be vacant. • The sum of the individual 2006 parcel populations was confirmed to equal the city-wide 2006 population estimate from the State Department of Finance. This outcome is assured because the number of dwelling units in the tax assessor’s database is consistent with the number of dwelling units in the California Department of Finance estimate. • The population in each model subcatchment was computed by summing the populations from each of the residential parcels within that subcatchment. • Per-capita unit flow rates and diurnal profiles (hourly variations) were assigned during model calibration to achieve a reasonable match to the 2007 temporary flow monitoring data. A per- capita flow rate of 65 gallons per day was determined to be appropriate for all parts of the City.
The calibrated diurnal profile for residential flows is shown on Figure 4-2. Additional information on model calibration is included in Appendix A.
City of Downey System Evaluation and Capacity Assurance Plan Chapter 4 Existing and Future Wastewater Flows
May 2009 4-7
Figure 4-2: Calibrated Diurnal Profiles
0 0.2
0.4 0.6
0.8 1
1.2 1.4
1.6 1.8
2 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Residential
Commercial
Coca-Cola Plant
Diurnal FactorHour of day
4.3.2 Non-Residential Flow
Metered water use most closely approximates wastewater generation during the winter months, when water demand is lowest due to reduced irrigation. Existing non-residential flow was estimated based on water consumption data and distributed to City parcels as follows:
• Figure 4-3 shows that water usage was at a minimum during the months of February through April, corresponding to the bimonthly meter readings taken in April and May. Water billing data for this period was geocoded to all non-residential parcels (approximately 1,000 parcels). • Water use was multiplied by a factor of 0.9 to account for residual irrigation and consumption.
This factor and the diurnal profiles (hourly variations) were finalized during calibration to the 2007 temporary flow monitoring data.
Diurnal profiles (hourly variations) were assigned during model calibration to achieve a reasonable match to the 2007 temporary flow monitoring data. The calibrated diurnal profile for non-residential flows is shown on Figure 4-2. Additional information on model calibration is included in Appendix A.
City of Downey System Evaluation and Capacity Assurance Plan Chapter 4 Existing and Future Wastewater Flows
May 2009 4-8
Figure 4-3: Metered Monthly Water Use (2005-2006)
0 10
20 30
40 50
60 Aug-05Sep-05Oct-05Nov-05Dec-05Jan-06Feb-06Mar-06Apr-06May-06Jun-06Jul-06Aug-06Sep-06Oct-06Nov-06Dec-06Water consumption, 100CF/meterMonth of water usage
4.3.3 Major Dischargers
Individual non-residential dischargers may vary in terms of the percentage of their water use discharged to the sewer system, but applying a uniform factor of 0.9 is adequate for typical dischargers. However, because of its extremely high and unique water usage, the Coca Cola Plant located at 11536 Patton Rd was researched further with the Industrial Waste Section of CSDLAC. Wastewater leaving the plant is directly metered, and the average flow for 2006 was 0.45 mgd. The diurnal flow profile (hourly variations) for this discharger was modeled as a constant (24 hours/day) flow. The plant discharges directly to CSDLAC’s Downey-Bellflower trunk sewer in Lakewood Blvd. at Cleta St.
4.3.4 City of Pico Rivera
Two CSDLAC trunk sewers (Old River School Trunk and Downey-Bellflower Trunk) collect wastewater from the City of Pico Rivera prior to entering Downey from the north. In order to estimate Pico Rivera’s flows, two flow meters were installed on those trunk sewers near the boundary between the cities as part of the 2007 temporary flow monitoring program. The monitored flows were directly input to the model at the two locations to represent existing Pico Rivera flows.
4.4 Buildout Dry Weather Flow
Similar to the existing (2006) dry weather flows, projected flows at buildout of the City were estimated at the parcel level and then aggregated into subcatchments for loading to the hydraulic model. The buildout land use category of each parcel was determined based on the 2025 General Plan database received from the City’s Planning Department. Figure 4-4 illustrates the land use designations from the General Plan.
Details follow on how the General Plan information was used to generate buildout dry weather flows for residential and non-residential land uses, as well as for major dischargers and Pico Rivera.
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City of DowneySystem Evaluation and Capacity Assurance Plan Figure 4-4: General Plan LandUse Designations
´Legend
Low Density Residential
Low - Med Density Residential
Medium Density Residential
Neighborhood Commercial
General Commercial
Commercial Manufacturing
Office
General Manufacturing
Open Space
Public
Schools
Mixed Use
City of Downey System Evaluation and Capacity Assurance Plan Chapter 4 Existing and Future Wastewater Flows
May 2009 4-10
4.4.1 Residential Flow
Buildout residential dry weather flow was estimated and distributed to City parcels as follows:
• In accordance with the City’s 2025 General Plan, it was assumed that all developed residential parcels would eventually increase in density to the maximum net densities specified in the 2025 General Plan for each land use category:
o Single Family Residential (SFR) = 1 DU/parcel
o Low-Medium Density Residential (LMDR) = 17 DU/acre
o Medium-Density Residential (MDR) = 24 DU/acre
o Mixed Use = 24 DU/acre
• All existing vacant parcels were also assumed to be developed at maximum density. • SFR units located within a Second Unit Development (SUD) Area were assigned a density of 2 DU/parcel.
• The number of DUs was multiplied by household size (cap/DU) to compute buildout population for each parcel. Since household sizes typically vary based on land use category, an analysis of current household sizes was performed using data from the Year 2000 census blocks which isolated each type of residential land use. The following were found to be the average household sizes (as adjusted by 4 percent to represent 2006 conditions):
o Single Family Residential (SFR) = 3.48 cap/DU (ranged from 1.56 to 5.45) o Low-Medium Density Residential (LMDR) = 3.78 cap/DU (ranged from 2.55 to 4.95) o Medium-Density Residential (MDR) = 3.04 cap/DU (ranged from 2.33 to 3.38) o Mixed Use = 3.04 cap/DU (assumed similar to MDR – no census data on this category) • Application of these category-specific household sizes to the General Plan land uses indicates that the average household size may further increase from 3.28 to 3.34 at buildout. • It was assumed the calibrated unit flow rates (gpd/cap) and diurnal profiles (hourly variations) based on the 2007 temporary flow monitoring data would also apply in the future. This effectively means that no further reductions in wastewater flows were assumed for future indoor water conservation efforts.
4.4.2 Non-Residential Flows
Buildout non-residential flow was estimated and distributed to City parcels as described below:
• For developed non-residential parcels that are not projected to change land use in the General Plan, the current wastewater flows based on water meter readings are assumed to remain the same at buildout.
• For vacant and redeveloping non-residential parcels (i.e. parcels with future land use that differs from existing land use), wastewater flows were estimated by applying category-specific per-acre flow factors (gpd/acre). The following factors were determined by summing the current parcel- based wastewater flows computed from water billing records within each land use category, and dividing by the total net acres of land in that category:
o Office = 1,000 gpd/acre
o Neighborhood Commercial = 1,300 gpd/acre
o General Commercial = 1,500 gpd/acre
o Manufacturing = 800 gpd/acre
o Schools = 15 gpd/student
City of Downey System Evaluation and Capacity Assurance Plan Chapter 4 Existing and Future Wastewater Flows
May 2009 4-11
• Special wastewater flow estimates for the Downey Landing Specific Plan were applied (flows come from the Downey Landing Specific Plan EIR) :
o Media center, museum and commerce center = 0.45 mgd 1 o Kaiser hospital = 0.2 mgd
2 4.4.3 Major Dischargers
Coca-Cola wastewater flow was assumed to remain the same as the current flow of 0.45 mgd. Although the plant has expanded to an adjacent 7-acre parcel, there are no plans to modify water consumption or wastewater flows.
4.4.4 City of Pico Rivera
Buildout flows from the two Pico Rivera basins were estimated by scaling up the measured existing flow hydrographs by factors that represent future growth. The scaling factors were computed by comparing the SCAG 2030 population and employment projections to the 2006 estimates for the appropriate census tracts. For the total of both basins, population is projected to increase by 12 percent and employment by 22 percent. These two percentage increases were combined by assuming that per-capita residential flows are 3 times per-employee flows (typical ratio observed in other cities). The composite scaling factor was thus computed to be 15 percent for the two Pico Rivera basins.
4.5 Dry Weather Flow Summary
Table 4-3 summarizes the existing and buildout population, dwelling units, household size, residential flow, non-residential flow, and total dry weather flow estimates.
Table 4-3: City of Downey Dry Weather Flow Summary
Existing (2006) Buildout (2030)
Population 112,985 125,245
Dwelling Units 34,490 37,457
Household Size 3.28 3.34
Average Residential Flow (mgd) 7.34 8.14
Non-Residential Flow,
excl. Coca-Cola Plant (mgd) 1.47 1.98
Coca-Cola Plant Flow (mgd) 0.45 0.45
Total Average Dry Weather Flow (mgd) 9.26 10.57
The existing population matches the State Department of Finance estimate for 2006, and the number of dwelling units and average household sizes are consistent with SCAG estimates. The projected buildout population reflects an 11 percent increase from 2006. That projection appears to be reasonable in comparison with SCAG’s projected increase of 9 percent between 2006 and 2030 (SCAG does not project buildout populations).
With regard to non-residential flows, the projected increase is due primarily to the projected flows in the Downey Landing redevelopment area. The projected increase in non-residential flow between 2006 and buildout, including the Coca-Cola Plant, is about 27 percent. This percentage increase is significantly
1 The retail center of the Downey Landing Specific Plan is already active; therefore, the flows associated with the center were included according to the Existing Flow methodology. 2 After completion of the hydraulic modeling analysis, hospital designers re-estimated an average water consumption of 750gpm for the hospital.
City of Downey System Evaluation and Capacity Assurance Plan Chapter 4 Existing and Future Wastewater Flows
May 2009 4-12
higher than SCAG’s projected increase in employment of 8 percent between 2006 and buildout. This is not unreasonable, however, as the SCAG employment projections were made prior to the release of the Downey Landing redevelopment plans, and non-residential flows are not necessarily proportional to employment numbers.
4.6 Wet Weather Flow Assumptions
Infiltration and inflow (I/I) of groundwater and storm water into sewers during and following wet weather events occur to varying degrees in all sewer systems. The magnitude of I/I varies widely from system to system depending on such factors as soils and topography, groundwater levels, rainfall depth and intensity, existence of illegal direct connections to the sewer system, and the prevalence of manhole and pipe defects. Many wastewater agencies include an allowance for I/I from a design event when analyzing sewer capacity and sizing new sewers, whether based on actual monitored I/I rates throughout the system, a higher peaking factor applied to dry weather flows, or a capacity criteria that reserves some of the pipe capacity beyond what is used by the peak dry weather flow.
An attempt was made to monitor actual wet weather flows throughout the City, but the lack of significant rainfall during the 2007 temporary flow monitoring period precluded developing I/I values specific to the City’s sewer system. Instead, the capacity analysis was performed based primarily on peak dry weather flows, but with relatively conservative hydraulic capacity criteria that effectively reserved some of the pipe capacity for I/I (as described in Chapter 5).
In addition to the dry weather flow analysis, a wet weather flow analysis was performed using “hypothetical” I/I hydrographs based on flow monitoring data obtained from the Orange County Sanitation District (OCSD). The wet weather flow analysis was not used to identify capacity deficiencies, but was performed to provide a more conservative peak flow for sizing of any relief sewers that might be required. The wet weather analysis also was used to identify areas that might be most at risk of SSOs during wet weather, where future flow monitoring efforts could be focused.
I/I hydrographs were based on data from OCSD, which performed an extensive amount of flow monitoring (up to 150 meters) between 2002 and 2005, and used the data to calibrate a wet weather flow model. OCSD also developed a 10-year return period design storm and applied it to develop I/I hydrographs in hundreds of subcatchments. Many of those subcatchments have similar characteristics to the City’s, including pipe age, material, topography, and climate. The OCSD wet weather peak design flows were analyzed and it was determined that the most common range of peak I/I in subcatchments was between 2,000 and 2,500 gallons per day per acre (gpad), with 37 percent of the subcatchments falling in this range. Also, slightly over half of the subcatchments had values less than or equal to 2,500 gpad.
Based on this analysis, I/I hydrographs having a peak flow rate of 2,500 gpad were applied to all the City’s subcatchments to represent “hypothetical” I/I from a severe storm event for use in the wet weather analysis. For the wet weather analysis, the I/I hydrographs were timed to coincide with the evening dry weather flows, which is consistent with the timing of the actual storm that OCSD used in their analysis.
Figure 4-5 illustrates a typical subcatchment wet weather hydrograph simulated using the above-described methodology. For subcatchments in the City, the “hypothetical” peak wet weather flows are generally in the range of 2 to 3 times the peak dry weather flows. It must be emphasized that there is no evidence from flow monitoring or observed water levels during storms that peak wet weather flows of this magnitude have occurred in the past or will occur in the future in the City’s sewer system. This limitation of the wet weather analysis was considered in the capacity analysis, which is presented in the following chapter.
City of Downey System Evaluation and Capacity Assurance Plan Chapter 4 Existing and Future Wastewater Flows
May 2009 4-13
Figure 4-5: Typical Subcatchment Wet Weather Hydrograph
City of Downey System Evaluation and Capacity Assurance Plan Chapter 5 Sewer System Capacity Analysis
May 2009 5-1
Chapter 5 Sewer System Capacity Analysis
The hydraulic capacity of the sewers must be sufficient to convey peak wastewater flows. The calibrated hydraulic model was used to generate design flows and to identify capacity deficiencies. This chapter presents the results of the capacity analysis performed for both dry and wet weather flows under existing and buildout conditions.
5.1 Capacity Analysis Criteria
A capacity deficiency requiring improvement was considered to exist when the ratio of flow depth to pipe diameter (d/D) at peak dry weather flow exceeded 75 percent under either existing or buildout conditions.
The rationale for applying this d/D ratio is that a pipe flowing that full during the peak hour of a dry weather day has a relatively high risk of surcharging under (as yet unmetered) peak wet weather flow conditions.
As noted previously, the wet weather modeling results were not used to identify capacity deficiencies since they are “hypothetical” and not supported by flow monitoring data. However, wet weather model runs were made to quantify d/D and the extent of potential surcharging in all pipes, and to estimate potential peak wet weather flows in deficient pipes for sizing improvements. Any required improvements would be sized to handle the design peak wet weather flow at a d/D of 75 percent. A Manning’s friction factor of 0.013 was assumed in all pipes for both dry and wet weather analyses.
5.2 Dry Weather Flow Analysis
The calibrated model was run for design dry weather flows under both existing and buildout conditions.
Figure 5-1 and Figure 5-2 present the maximum depth-to-diameter ratios for these two conditions.
The figures show that under both existing and buildout conditions, most of the City’s sewers and the CSDLAC trunk sewers flow at less than 50 percent full in dry weather. Some of the larger sewers, mostly trunk sewers, flow at 50 to 75 percent full. At buildout, there are two trunk sewers which are projected to exceed 75 percent of pipe diameter. These are the CSDLAC trunks on Burns Ave. and Lakewood Blvd.
In regards to the Lakewood Blvd. TS, there are two locations in the downstream reaches which are projected to exceed 75 percent of pipe diameter. Two of the City sewers connecting to this trunk sewer are affected by backwater at their connection points and a short distance upstream. The high water levels projected for those City sewers are due to backwater from the Lakewood Blvd. trunk sewer. Where a 12” City sewer on Stewart and Gray Road connects to the 21” trunk sewer on Lakewood Blvd., it was assumed that the inverts of the two lines matched, when in reality there is a drop. Where a City sewer on Clark Ave. connects to the Lakewood Blvd. trunk, a datum mismatch makes the Clark Ave. line appear to connect below the elevation of the Lakewood Blvd. trunk. Both of these cases are due to inconsistencies in the GIS data and are not actual capacity problems.
High depth-to-diameter ratios in the CSDLAC Burns Ave. trunk are seen in pipes located downstream of a flow split at Second Ave and New St. A temporary flow meter installed on this line indicated that all flow is diverted to the Burns Ave line at the flow split, which results in a capacity deficiency under buildout conditions. This deficiency could be avoided if the flow split were optimized to divert some flow to the Old River School Road TS on Second Ave. It is recommended that the City look into diverting more flow to CSDLAC’s Old River School Rd. trunk to resolve this deficiency.
Based on the dry weather flow analysis and the considerations described above, all of the City’s sewers meet the capacity criteria under both existing and buildout conditions. No improvement projects are required for the City’s sewer mains.
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!LAKEWOODFI
RE
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ROSECRANS
1 Miles
City of Downey
System Evaluation and Capacity
Assurance Plan
Figure 5-1: 2006 Dry Weather Flow
Maximum Depth-to-Diameter Ratio
Maximum Pipe d/D
0.5 - 0.75
Surcharged
!Modeled Manhole
R Overflowing Manhole
less than 0.5
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City Limits
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!LAKEWOODFI
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P
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ROSECRANS
1 Miles
City of Downey
System Evaluation and Capacity
Assurance Plan
Figure 5-2: 2030 Dry Weather Flow
Maximum Depth-to-Diameter Ratio
Maximum Pipe d/D
0.5 - 0.75
Surcharged
!Modeled Manhole
R Overflowing Manhole
less than 0.5
Unmodeled Sewers0.75 - 1.0
City Limits
City of Downey System Evaluation and Capacity Assurance Plan Chapter 5 Sewer System Capacity Analysis
May 2009 5-4
5.3 Wet Weather Flow Analysis
The model was also run for the “hypothetical” 10-year return period peak wet weather flows under both existing and buildout scenarios. As emphasized previously, there is no flow monitoring or other evidence to indicate that peak flows of this magnitude have or will occur in Downey. Due to this limitation, the wet weather flow analysis was not used to identify capacity deficiencies, but was performed to identify areas that might be most at risk of SSOs during wet weather, where future flow monitoring efforts could be focused. The wet weather flow analysis was also intended to provide a more conservative peak flow for sizing of any relief sewers that might be required based on dry weather flow, but no relief sewer projects were found to be necessary. Figure 5-3 and Figure 5-4 present the maximum depth-to-diameter results of the “hypothetical” wet weather flow analysis under existing and buildout conditions.
The wet weather analysis indicated that for both existing and buildout peak wet weather conditions, many sewers could potentially flow full or surcharge, particularly the CSDLAC trunk sewers. However, despite widespread surcharging in the model, overflows were not predicted. Additional monitoring and capacity analysis should focus on the Lakewood Blvd. trunk sewer, as recommended in the capacity assurance plan presented in Chapter 6.
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City of Downey
System Evaluation and Capacity
Assurance Plan
Figure 5-3: "Hypothetical" 2006
Wet Weather Flow Capacity Analysis
Maximum Pipe d/D
0.5 - 0.75
Surcharged
!Modeled Manhole
R Overflowing Manhole
less than 0.5
Unmodeled Sewers0.75 - 1.0
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City of Downey
System Evaluation and Capacity
Assurance Plan
Figure 5-4: "Hypothetical"2030
Wet Weather Flow Capacity Analysis
Maximum Pipe d/D
0.5 - 0.75
Surcharged
!Modeled Manhole
R Overflowing Manhole
less than 0.5
Unmodeled Sewers0.75 - 1.0
City Limits
City of Downey System Evaluation and Capacity Assurance Plan Chapter 6 Recommended Capacity Assurance Plan
May 2009 6-1
Chapter 6 Recommended Capacity Assurance Plan
The capacity analysis indicated that the City’s sewer system has adequate capacity under existing (2006) and buildout (2030) peak dry weather flow conditions, with some reserve capacity for conveying I/I.
Therefore, no capital improvement projects are required to relieve the system.
The wet weather flow analysis, based on “hypothetical” I/I hydrographs for a 10-year return period storm taken from the OCSD monitoring and modeling study, indicates a potential for surcharging in several of the CSDLAC trunk sewers and some of the City’s sewers. The overflow risk appears to be highest in the upper reaches of the Lakewood Blvd. trunk sewer and City sewers connected to that trunk. Since the wet weather analysis was not based on actual monitored wet weather flows in the City, the results are most appropriately used as a basis for prioritizing future monitoring efforts. To this end, the modeled peak depth of flow in all City sewers was examined to identify locations having the highest likelihood of significant surcharging during a major wet weather event.
Wet weather flow monitoring is costly due to the amount of time the monitors must be operated in order to have a reasonable chance of capturing a major storm event. As evidenced by the City’s 2007 temporary flow monitoring program, there is a risk of not capturing any useful wet weather data at all.
Rather than implement another wet weather flow monitoring program, we recommend that the City first install several surcharge monitors at the 25 locations indicated in Figure 6-1 and Table 6-1, which are the manholes most likely to surcharge significantly based on the wet weather analysis.
Surcharge monitors are passive devices that record only the highest water levels experienced during a storm event. Examples of surcharge monitors would be a series of small cups attached at various depths in a manhole, which could be inspected following a storm to determine the depth of surcharging by observing the highest cup that is filled. Another type of monitor is a special paint or coating placed on the manhole wall that changes in a visible way when wetted by surcharging. The surcharge monitors should be set prior to the wet weather season and then checked after major storms and re-set (i.e., empty cups or replace coating) if surcharging occurs.
Surcharge monitoring should be continued until the extent of surcharging during major storms can be ascertained. In locations where surcharging does not occur or is not sufficient to pose an overflow threat (remains five feet below ground level) during a projected design event, the monitors could be removed. If any sewers were found to surcharge enough to pose an overflow risk, additional action should be taken.
The likely first step would be to install regular temporary flow meters upstream of the surcharged sewer to determine the source and magnitude of the I/I. Following that determination, the next step could be the design of a City relief sewer, notification to CSDLAC of the need to relieve their trunk sewer, or additional field investigations aimed at identifying and reducing the sources of I/I.
In addition to surcharge and flow monitoring, the City should use the hydraulic model to assess the impacts of future developments that deviate significantly from those that are currently included in the model. The existing model should be maintained and refined according to the specific recommendations presented in Appendix A. Since the CSDLAC-owned Lakewood Blvd. trunk sewer system has been identified as having the highest risk of overflows, it should be the highest priority for model refinement as well as monitoring.
City of Downey System Evaluation and Capacity Assurance Plan Chapter 6 Recommended Capacity Assurance Plan
May 2009 6-2
Table 6-1: Recommended Surcharge Monitoring Locations
Downey Manhole ID
SMN0703003
SMN2019004
SMN0782003
SMN0798003
SMN0811004
SMN1084002
SMN2398001
SMN1117001
SMN1171003
SMN2483003
SMN0394001
SMN1517003
SMN1346003
SMN1706001
SMN2016004
SMN0595004
SMN1954003
SMN2282002
SMN2300003
SMN2496001
SMN0060002
SMN0055001
SMN2512003
SMN2514004
SMN2505001
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City of DowneySystem Evaluation and Capacity Assurance Plan Figure 6-1: Recommended Surcharge Monitoring Locations
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Downey City Limits
Major Streets
County Trunks
Downey Sewers
Appendix A - Dry Weather Model
Calibration
1 Memorandum Wat er andEnvironment
Downey SSMP
Subject: Model Calibration Notes
Prepared For: Paul Giguere
Prepared by: Alison Hill
Date: August 27, 2007 (REVISED May 2009)
This memo is a summary of the model calibration results by flow meter. Tables 1 through 3 compare metered vs. modeled flow for each of the meters under average and peak conditions. The tables show that 17 of the 21 meters are within 20% of average modeled flow, and that 18 of the 21 meters are within 20% of peak modeled flow.
Metering data from the first week of March was used for the initial calibration (metering period was from the beginning of February to the end of March). Upon further review of the data, it was discovered that the reported flows for several of the meters had increased over time. The initial flows at the start of the monitoring period, which had been field-checked when the meters were installed, are considered to be more accurate. To correct the effects of drifting, data from before the drifting started (usually at the beginning of February) was used for meters C1, C2, C3, C5, C9, and D4. This change significantly improved the original calibration results.
Theoretical flows based on application of Manning’s formula were computed for all meters, and are reported on Table 1 for comparison to the depth-velocity flows. The accuracy of these theoretical flows is subject to the validity of the assumed slope and friction factors, and the existence of uniform flow conditions at the meter (i.e., no disturbances that result in backwater or hydraulic drops). If the sensors are operating properly, the flows based on the measured depth and velocity (before drifting) should be more accurate since they do not depend on those limiting assumptions. Following the revisions to minimize the drifting effect, the measured velocities are likely to be reasonably accurate, and so the depth-velocity flows were used to compute the % differences in the tables and are the flows shown on the calibration plots.
The following paragraphs are comments on the calibration results for each of the meters. Following these comments are Tables 1-3, meter location maps, and plots comparing the metered flows to the modeled flows.
Meter C1: Meter C1 is located on the Old River School Road Relief TS. The Old River School Road Relief TS and the Old River School Road TS are the two county trunks which accept flow from the western half of Downey. It is unknown how flow is split between these two trunks. CSDLAC Meter 712 is on the Old River School Road TS and agrees with the model. CSDLAC Meter 834 is on the Old River School Road Relief TS and agrees with the model. Meter C1 reads 1cfs higher than the model, but is still within 20% of the model.
Meters C2 and C3: Meters C2 and C3 are downstream of the flow split at Lakewood and Clark. The sum of these meters approximately matches the model. Invert elevation data for this flow split was not available, so the exact configuration of this flow split is unknown. In order to get the correct distribution of flow to Meters C2 and C3, the invert elevation of the pipe to Meter C2 was raised by 0.25ft. This resulted in a good match at both meters; however, the relative inverts of this line should be investigated further.
Downey SSMP
Model Calibration
2 Meters C4 and C5: According to conversations with Darrel Hatch of CSDLAC, Meters C4 and C5 measure all flow from the Woodruff Ave TS and the East Compton Blvd TS. Data from CSDLAC Meter 344 in December of 2006, however, indicates that 0.5 cfs exits the system through an additional trunk line that was not considered in the modeling analysis. There are several flow splits upstream of these metering sites, so the origin of this additional flow is difficult to pinpoint. There is a very good match between model and meter at sites C4 and C5.
Meters C6 and C7: Meters C6 and C7 are downstream of a flow split at Florence and Rives. All flow goes south on Rives Ave. towards Meter C7. The model agrees with the meter that there should be zero flow at Meter C6. The average modeled flow is within 20% of the metered flow at C7. Modeled flow is a little low.
Meter C8: Meter C8 is downstream of a flow split at Lakewood and Cecilia. There is a satisfactory match between meter and model, at peak flow the match is within 20%. Modeled flow is a little high.
CSDLAC Meter 190 agrees with Meter C8.
Meter C9: Metered and modeled flows are within 20% for average and peak.
Meter C10: The flow for this meter was input directly into the model.
Meter C11: The flow for this meter was input directly into the model.
Meter D1: Metered and modeled flows are within 15% for average and peak.
Meter D3: Meter D3 was installed in two different locations during the monitoring period. The first location was on Paramount Blvd, north of Gallatin, and is referred to as Site D3A. The second location was on Samoline Ave, south of Gallatin, and is referred to as Site D3B. Site D3B was the intended site for the model calibration. Upon comparing the data for Sites D3A and D3B, it was observed that D3A flow was higher than D3B, which is difficult to understand because Site D3A is upstream of Site D3B. It was concluded that the data for these two sites was accidentally switched. The model confirms that this was the case as there is a good match between the D3A flows at the D3B site. Therefore, D3A flows were used for the model calibration, and D3B flows were disregarded.
Meter D4: Meter D4 is downstream of a flow split at Second St and New St. A field survey was conducted to validate the operation of this flow split; however, it was not possible to accurately simulate the field conditions using the model. The metering indicates that flow must have been blocked in the pipe headed west from the flow split. Assuming that flow is blocked to the west, a good match between model and meter is achieved.
Meter D6: Metered and modeled flows are within 10% for average and peak.
Meter D7: There is very low flow at this metering site, which exaggerates the percent matching of average flow between meter and model. The peak flows are within 10% of each other.
Meter D8: Metered and modeled flows are within 20% for average and peak.
Meter D9: Metered and modeled flows are within 20% for average and peak.
Meter D10: Initially, the modeled flows were much higher than metered flows at this site. A field investigation showed that there was a connection to a county line that was not indicated as such in the GIS. This connection is just upstream of Meter D10 and diverts a high quantity of flow away from D10.
Although there still appears to be an overestimate of commercial flow in the area, the peak modeled and metered flows are within 5% of each other.
Meter D11: Metered and modeled flows are within 15% for average and peak.
Meter D12: Meter D12 was installed in a line parallel to the Meter D11 line. It was thought that the two lines both carried flow from development along Bellflower Blvd. Meter D12 indicates that little to no
Downey SSMP
Model Calibration
3 flow is conveyed in the western line. The model agrees that there should be an insignificant amount of flow in this line.
Recommendations for model refinement:
1. Update the GIS to reflect sewer changes resulting from construction of Century Freeway.
2. Perform field survey of all flow splits. Get invert elevations.
3. Update the GIS to include all county trunks that accept flow from Downey, and ensure that all connections are correct.
Table 1: Meter vs. Model Average Flow Comparison – E2 Meters Meter Name
Ave Meter
Flow (cfs)
Ave Model
Flow (cfs)
Manning’s
Flow (cfs) % Difference
C1 4.645 3.784 5.575 -19%
C2 0.569 0.521 0.569 -8%
C3 3.765 3.362 2.636 -11%
C4 3.608 3.408 2.706 -6%
C5 1.641 1.576 1.559 -4%
C6 0.010 0.000 0.019 NA
C7 1.823 1.484 2.005 -19%
C8 1.342 1.641 1.476 22%
C9 0.631 0.674 0.467 7%
C10 0.593 0.588 0.653 -1%
C11 0.047 0.046 0.039 -2%
D1 0.276 0.315 0.469 14%
D3A 0.34 0.31 0.26 -9%
D4 0.778 0.805 0.544 3%
D6 0.558 0.572 0.558 2%
D7 0.103 0.137 0.113 34%
D8 0.214 0.212 0.152 -1%
D9 0.348 0.416 0.487 20%
D10 0.354 0.462 0.443 30%
D11 0.567 0.534 0.510 -6%
D12 0.013 0.000 0.026 NA
Total 22.125 20.447 -8%
Downey SSMP
Model Calibration
4 Table 2: Meter vs. Model Peak Flow Comparison – E2 Meters Meter Name
Peak Meter
Flow (cfs)
Peak Model
Flow (cfs) % Difference
C1 7.030 5.475 -22%
C2 0.940 0.698 -26%
C3 5.241 4.504 -14%
C4 5.368 4.917 -8%
C5 2.560 2.292 -10%
C6 0.217 0.000 NA
C7 2.606 2.159 -17%
C8 1.994 2.351 18%
C9 1.110 1.032 -7%
C10 0.954 0.842 -12%
C11 0.080 0.065 -18%
D1 0.434 0.474 9%
D3A 0.698 0.577 -17%
D4 1.240 1.125 -9%
D6 0.925 0.862 -7%
D7 0.198 0.217 9%
D8 0.379 0.313 -17%
D9 0.628 0.637 2%
D10 0.680 0.667 -2%
D11 0.900 0.794 -12%
D12 0.050 0.000 NA
Table 3: Meter vs. Model Comparison – CSDLAC Meters
Meter Name
Meter Flow
(cfs)
Model Flow
(cfs) % Difference
712 1.5 1.7 12%
834 4.0 3.8 -5%
M02919
M03027
M02378
M03026
M03025
M03028
M02918
M08435
M02377
M02917
M02376
M04404
M03024
M03029
M04147
M02916
M02915
M03022
M02914M03023M03021
M04148
M02375
M04403
M03046
M08434
M02912M03020
M04149
M03047
M02374
M02911
M04150
M03048
M04402
M03019
M04151
M02373
M03049
M08433
M02910
M08432
M02909
M04152M08431
M03050
M02908
M03018
M02372
M04401
M02907
M04153
M02371
M03051
M02906
M03017
M02905
M02370
M03052M08430
M04400
M02904
M04154
M02903
M03016
M03053
M04155
M02369
M02368
M02902
M03054
M04156
M02901
M04157
M04399
M03015
M03061
M03055
M03060
M02367
M03056
M08429
M04158
M03059
M03062
M02900
M03057
M02899M03014
M04159
M04398
M03063
M02830
M02366
M03058
M02898
M04160
M03064
M03013
M08428
M03005
M03004
M03003
M02656
M02897
M03065
M02365
M03006
M04397
M02829
M03066
M02655
M03012
M02364
M03007
M02896
M02363
M08427
M04396
M02828
M03008
M03011
M02895
M02894
M02654
M03009
M02362
M02361
M02865
M02893M03010
M02864
M08426
M02827
M04395
M02360
M02653
M02892
M02826
M04394
M02825
M02359
M08425
M02891
M02652
M02863
M02824
M02358
M02890
M04393
M02862
M08424
M02651
M02823
M02357
M02889
M02356
M02888
M02861M02860
M02822
M02859
M02887
M04392
M02886
M02821
M02858
M08423
M02820
M02355
M02885
M04391
M02819
M04390
M02857
M02354
M07603
M08422
M02353
M02884
M02818
M02856
M04389
M02883
M02817
M02855
M02352
M02882
M02881
M08421
M02351
M02854
M02816
M02880
M04388
M02815
M02853
M04387
M02350
M02813
M04386
M02812
M02814
M02807
M02808
M07602
M02879
M08420
M02878
M02811
M02809
M02349
M02348
M02852
M02877
M02810
M02806
M04385
M07601
M02873
M02347
M02874
M02875
M02876
M08419
M02805
M02851
M07599
M07598
M04384
M08418
M02804
M02346
M02803M02850
M04383
M07597
M02802
M07596
M07595
M02345
M07403
M02642
M04382
M02344
M02801
M02849
M07594M08417
M04381
M02343
M02800
M02641
M02342
M02848
M02799
M04380
M02798
M07593
M19854
M02341
M07592
M08416
M02797
M04379
M02640
M02796
M02340
M02847
M08415
M02795
M02339
M04378
M04377
M02846
M02794
M02338
M07591
M07614M08414
M07590
M02845
M04376
M02793M02792
M08413
M02337
M02791M02844
M02843
M07589
M02842
M02790
M04375
M02789
M02336
M07588
M02335
M02841
M07587
M02788
M04374
M02334
M07586
M02840
M02787
M02333M02332
M02786
M02576
M02585
M02331
M02584
M02583
M02582
M02839
M02575
M02577
M02785
M02581
M04373
M04370
M07585
M02330
M02574
M02580
M02578
M02838
M04371
M02329
M02579
M02784
M02573
M02328
M02837
M04369
M02572
M04368
M04367
M04359
M04360
M04366
M04365
M04364
M04363
M04362
M04361
M04491
M04497
M04496
M04495
M02327
M04492
M04446
M04494
M04445
M08297
M04493
M02783M02782
M19789
M02568
M02569
M04526
M02836
M08296
M02567
M04444
M04358
M04443
M02781
M02570
M02566
M02326
M02835
M02780
M07583
M02779
M04357
M02325
M02834
M02833
M02778
M02565
M02775
M02832
M02774
M02776
M02777
M07582
M02773
M04356
M02324
M02563
M02564
M02562
M02561
M02560
M02559
M20040
F00000
F00000
M07522
M07521
M07520
M19900
M21181
M21180
M21179
M21178
M21177
M21176
M21175
M21174
M21173
M21864
M21863
M21867M21866
M21873
M21876
M21875
M21874
M21871M21870
M21869M21868
M22681
M23268
M23275
M23310
M21865
M23967LAKEWOOD
BLVDCENTURYIMPERIAL
AV
R
D
FLORENCEAVFIRESTONEHWYPARAMOUNTB
L
BLVDBELLFLOWER
SANTAANABLVDFRWY)FRWYWOODRUFF DOWNEY
A
V OLD
RIV
ER
SCHOOLH289B156A1959897756A438874834728884890A197B123A18821832266405407424190614615626632640688648NDISTRICTS SEWERSLOCAL SEWERSLEGENDcompton\jganz\flomegterloc.dgnLOS ANGELES COUNTY SANITATION DISTRICTS METER LOCATIONSCITY OF DOWNEYM04372 H1018 FLOW DIRECTION3442164395712260
C1 Flow Data vs Model Data0.001.002.003.004.005.006.007.008.0012:00:00 AM 12:00:00 PM 12:00:00 AM 12:00:00 PM 12:00:00 AMDateFlow (cfs)Flow DataModel Data
C2 Flow Data vs Model Data0.00.10.20.30.40.50.60.70.80.91.012:00:00 AM 12:00:00 PM 12:00:00 AM 12:00:00 PM 12:00:00 AMDateFlow (cfs)Flow DataModel Data
C3 Flow Data vs Model Data0.0001.0002.0003.0004.0005.0006.00012:00:00 AM 12:00:00 PM 12:00:00 AM 12:00:00 PM 12:00:00 AMDateFlow (cfs)Model DataFlow Data
C4 Flow Data vs Model Data0.001.002.003.004.005.006.0012:00:00 AM 12:00:00 PM 12:00:00 AM 12:00:00 PM 12:00:00 AMDateFlow (cfs)Flow DataModel Data
C5 Flow Data vs Model Data0.000.501.001.502.002.503.0012:00:00 AM 12:00:00 PM 12:00:00 AM 12:00:00 PM 12:00:00 AMDateFlow (cfs)Flow DataModel Flows
C6 Flow Data vs Model Data0.000.050.100.150.200.250.300.350.400.450.5012:00:00 AM 12:00:00 PM 12:00:00 AM 12:00:00 PM 12:00:00 AMDateFlow (cfs)Flow DataModel Flows
C7 Flow Data vs Model Data0.000.501.001.502.002.503.0012:00:00 AM 12:00:00 PM 12:00:00 AM 12:00:00 PM 12:00:00 AMDateFlow (cfs)Flow DataModel Data
C8 Flow Data vs. Model Data0.000.501.001.502.002.5012:00:00 AM 12:00:00 PM 12:00:00 AM 12:00:00 PM 12:00:00 AMDateFlow (cfs)Flow DataModel Flows
C9 Flow Data vs. Model Data0.000.200.400.600.801.001.2012:00:00 AM 12:00:00 PM 12:00:00 AM 12:00:00 PM 12:00:00 AMDateFlow (cfs)Flow DataMeter Data
C100.000.200.400.600.801.001.2012:00:00 AM 12:00:00 PM 12:00:00 AM 12:00:00 PM 12:00:00 AMDateFlow (cfs)Flow DataModel Data
C11 Flow Data vs. Model Data0.000.020.040.060.080.100.1212:00:00 AM 12:00:00 PM 12:00:00 AM 12:00:00 PM 12:00:00 AMDateFlow (cfs)Flow DataModel Data
D1 Flow Data vs. Model Data0.000.050.100.150.200.250.300.350.400.450.5012:00:00 AM 12:00:00 PM 12:00:00 AM 12:00:00 PM 12:00:00 AMDateFlow (cfs)Flow DataModel Data
D3 Model Data vs. Flow Data0.000.100.200.300.400.500.600.7012:00:00 AM 12:00:00 PM 12:00:00 AM 12:00:00 PM 12:00:00 AMDateFlow (cfs)Flow DataModel Data
D4 Flow Data vs. Model Data0.000.200.400.600.801.001.201.4012:00:00 AM 12:00:00 PM 12:00:00 AM 12:00:00 PM 12:00:00 AMDateFlow (cfs)Flow DataModel Data
D6 Flow Data vs. Model Data0.000.100.200.300.400.500.600.700.800.901.0012:00:00 AM 12:00:00 PM 12:00:00 AM 12:00:00 PM 12:00:00 AMDateFlow (cfs)Flow DataModel Data
D7 Flow Data vs. Model Data0.000.050.100.150.200.2512:00:00 AM 12:00:00 PM 12:00:00 AM 12:00:00 PM 12:00:00 AMDateFlow (cfs)Flow DataModel Data
D8 Flow Data vs. Model Data0.000.050.100.150.200.250.300.350.4012:00:00 AM 12:00:00 PM 12:00:00 AM 12:00:00 PM 12:00:00 AMDateFlow (cfs)Flow DataModel Data
D9 Flow Data vs. Model Data0.000.100.200.300.400.500.600.7012:00:00 AM 12:00:00 PM 12:00:00 AM 12:00:00 PM 12:00:00 AMDateFlow (cfs)Flow DataModel Data
D10 Flow Data vs. Model Data0.000.100.200.300.400.500.600.700.8012:00:00 AM 12:00:00 PM 12:00:00 AM 12:00:00 PM 12:00:00 AMDateFlow (cfs)Flow DataModel Data
D11 Flow Data vs. Model Data0.00000.10000.20000.30000.40000.50000.60000.70000.80000.90001.000012:00:00 AM 12:00:00 PM 12:00:00 AM 12:00:00 PM 12:00:00 AMDateFlow (cfs)Flow DataModel Data
D12 Flow Data vs. Model Data0.000.050.100.150.200.250.300.350.400.450.5012:00:00 AM 12:00:00 PM 12:00:00 AM 12:00:00 PM 12:00:00 AMDateFlow (cfs)Flow DataModel Data
Appendix
B Sewer Rehabilitation and Replacement Plan
City of Downey
Sewer Rehabilitation and
Replacement Plan
Prepared by:
May 2023
May 2023
Table of Contents
Introduction ................................................................................................................................ i Chapter 1 Sewer System Characteristics ............................................................................1-1 Chapter 2 Video Inspection Program ..................................................................................2-1
2.1 Characteristics of Pipes Selected ..........................................................................2-1
2.2 Inspections Performed ...........................................................................................2-4
2.3 Quality of Data .......................................................................................................2-4 Chapter 3 Assessment Methodology ..................................................................................3-1
3.1 Condition Grades ...................................................................................................3-1
3.2 Pipe Ratings ..........................................................................................................3-1
3.3 Recommended Actions for Structural Defects .......................................................3-2
3.4 Recommended Actions for Maintenance Defects ..................................................3-5 Chapter 4 Inspection Results and Short-Term Projects.....................................................4-1
4.1 Structural Condition ...............................................................................................4-1
4.2 Maintenance Condition ..........................................................................................4-1 Chapter 5 Long-Term Inspection, Rehabilitation and Replacement Program ..................5-3
5.1 Analysis of Results of Initial Inspections ................................................................5-3
5.2 Generalized Outcomes of Future Inspections ........................................................5-3
5.3 Projected 5-Year Inspection and Rehabilitation Requirements ..............................5-4
5.4 Projected Capital Costs .........................................................................................5-5 Chapter 6 Summary of Findings and Recommendations ..................................................6-1
6.1 Structural Condition ...............................................................................................6-1
6.2 Maintenance Condition ..........................................................................................6-1
6.3 Long-Term Inspection and Rehabilitation and Replacement Program ...................6-1
List of Tables
Table 1-1: Sewer System Characteristics 1-1
Table 2-1: Diameter of Sewers Selected for Initial Inspections 2-1 Table 2-2: Age of Sewers Selected for Initial Inspections 2-2 Table 3-1: PACP Condition Grading System 3-1
Table 3-2: PACP Pipe Condition Ratings 3-2
Table 3-3: Maintenance Condition Ratings 3-6
Table 4-1: Summary of Baseline Structural Condition Findings 4-1 Table 4-2: Summary of Baseline Maintenance Condition Findings 4-1 Table 5-1: Summary of Recommended Actions and Priorities by Pipe Generation 5-3 Table 5-2: Generalized Outcomes of Future Inspections by Clay Pipe Generation 5-4 Table 5-3: Recommended Re-inspection Intervals in Years 5-5 Table 5-4: Unit Costs for Video Inspection and Rehabilitation 5-6 Table 5-5: Annual Inspection and Rehabilitation/Replacement/Repair Costs 5-6
List of Figures
Figure 1-1: Distribution of Sewer by Clay Pipe Generation 1-2 Figure 2-1: Recommended Actions for Structural Defects 2-3 Figure 3-1: Recommended Actions for Structural Defects 3-4 Figure 3-2: Recommended Actions for Maintenance Defects 3-5
May 2023
Appendices
Appendix A - Hotspot Cleaning List
Appendix B - Root Control List
May 2023
List of Abbreviations
DSI Downstream Services Incorporated
MPR Maintenance Pipe Rating
MPRI Maintenance Pipe Rating Index
NASSCO National Association of Sewer Service Companies
OPR Overall Pipe Rating
OPRI Overall Pipe Rating Index
PACP Pipeline Assessment and Certification Program
QMR Quick Maintenance Rating
QSR Quick Structural Rating
RRP Rehabilitation and Replacement Plan
SPR Structural Pipe Rating
SPRI Structural Pipe Rating Index
SSMP Sewer System Management Plan
City of Downey Sewer Rehabilitation and Replacement Plan Introduction
May 2023 i
Introduction
This Sewer Rehabilitation and Replacement Plan (RRP) is updated in conjunction with updates to the City’s Sewer System Management Plan (SSMP). The RRP identifies specific short-term rehabilitation and replacement projects, and also provides estimates of future long-term needs that the City should anticipate and budget for over a five-year period. The RRP has been based on the characteristics of the City’s gravity sewer system, the baseline analysis of the results of video inspections of 5 percent of the system performed between April and July of 2007, and subsequent analyses conducted on an annual basis based on the City’s annual cleaning and video inspection programs. Video inspections are also analyzed to identify maintenance problems, and specific recommendations are made for addressing those problems.
The RRP also includes descriptions of the City’s current programs for video inspections and assessments of the sewer system.
The preparation of this RRP involved performing the following specific tasks:
· Baseline characterization of the existing sewers and selection of specific sewer pipes to be inspected (50,000 feet – 5% of the system).
· Establishment of standards for video inspections, including the defect coding system, data capture software, pipe and manhole identifiers, and video and image file formats. · Coordinating and performing quality control on the video inspections performed by contractors and City staff.
· Developing and implementing a system for quantifying the structural and maintenance condition and needs of individual sewer lines, selecting the appropriate action to be taken, and prioritizing and scheduling those actions.
· Establishing a program for video inspection and assessment of the sewer system. · Establishing a process for providing planning-level cost estimates for short-term and long-term inspections and rehabilitation and replacement projects.
This report is organized into the following chapters:
1. Sewer System Characteristics
2. Video Inspection Program
3. Assessment Methodology
4. Inspection Results and Short-Term Projects
5. Long-Term Inspection and Rehabilitation and Replacement Program
6. Summary of Findings and Recommendations
City of Downey Sewer Rehabilitation and
Replacement Plan
Chapter 1
Sewer System Characteristics
May 2023 1-1
Chapter 1 Sewer System Characteristics
The City’s sanitary sewer system is notable in that it is relatively old with an average age of over 60 years, the gravity sewers are all constructed of clay pipe, and there is very little pipe less than eight inches in diameter. The characteristics of the City’s sewer system are summarized in Table 1–1.
Table 1-1: Sewer System Characteristics
Characteristic Value
Total Length 193 miles
Range of Pipe Sizes 6 to 21 inch diameter; 93% is 8 inch diameter Material of Construction All gravity sewers are constructed of clay pipe Average Age 67 years; oldest sewer was installed in 1929; 85% installed prior to 1958
Due to the relative uniformity of the City’s sewer system in terms of pipe size and material, the year of construction is the most significant characteristic that should be an indicator of pipe condition. Besides the fact that older pipe has had a longer period in which to deteriorate, there are also differences in the pipe and joint materials that were commonly used during different historical periods in the evolution of clay pipe. Based on information provided by the National Clay Pipe Institute1, there have been three generations of clay sewer pipe:
· Generation 1 - Clay pipe manufactured before 1950 consists of short sections with joints every two to three feet. When compared with modern clay pipe, it has relatively thin walls and is only partially fired. This pipe is commonly referred to as “terra cotta” pipe. The joints are rigid and typically consist of cement mortar. The fragile nature of the pipes resulted in damage during construction and subsequent damage from earth movement and loss of support due to migration of fine soil particles and nearby underground construction. The cement mortar joints tend to deteriorate due to microbial-induced corrosion and cracking due to soil movement. Roots exploit the cracks and failed joints to gain access to water and nutrients and thereby cause further damage to the pipe.
· Generation 2 - Clay pipe manufactured between 1950 and 1958 consists of longer sections with joints every five to six feet. The pipe walls are thicker and the clay is fired to a greater extent.
This pipe is commonly referred to as vitrified clay pipe. The joints are rigid and typically consist of cement mortar. Sewers of this generation are less susceptible to damage during construction, but they are problematic due to the durability of the joints, as described above for terra cotta pipe. · Generation 3 - Clay pipe manufactured after 1958 was designed with flexible joints made of polyvinyl chloride and, later, synthetic rubber (polyurethane). Sewers of this generation perform well from an infiltration perspective.
The distribution of the City’s sanitary sewer system with respect to the generations of clay pipe is shown on Figure 1-1. The 5 percent of the pipes with unknown year of construction were assumed to be in Generation 1.
1 Adapted from National Clay Pipe Institute Chronology prepared by John Butler, dated August 23, 2005.
City of Downey Sewer Rehabilitation and
Replacement Plan
Chapter 1
Sewer System Characteristics
May 2023 1-2
Figure 1-1: Distribution of Sewer by Clay Pipe Generation Generation 1
29%
Generation 2
56%
Generation 3
15%
City of Downey Sewer Rehabilitation and
Replacement Plan
Chapter 2
Video Inspection Program
May 2023 2-1
Chapter 2 Video Inspection Program
As part of the baseline analysis, City Staff and consultant selected gravity sewers for inspection in 2007, with the target of inspecting 50,000 feet of pipe, approximately 5% of the City’s sewer system. The initial video inspection effort was intended to characterize the overall condition of the system to allow for a realistic projection of future rehabilitation and replacement needs. Subsequent year inspections were conducted via procurement of a contractor or using City sewer and stormwater operations staff with sewer location emphasis placed on recommendations from the baseline analysis and data collected from the City’s annual sewer cleaning program.
2.1 Characteristics of Pipes Selected
Sewers selected for the baseline inspection included a sampling of sewers built in various time periods, having the full range of diameters, and located in all parts of the city. Also included were the sewers from the City’s “Hotspot” preventive maintenance program, to assist in assessing maintenance requirements.
Table 2-1 shows the size of the sewers selected for inspection and the percentage of the collection system represented. Table 2-2 shows the age statistics of the sewers selected for inspection in comparison to the overall sewer system. Figure 2-1 shows the location of the pipes selected for inspection (actual pipes inspected differed somewhat from these selected pipes, as described later in this chapter). As can be seen, the selected pipes were located in all parts of the City and all pipe sizes were represented in approximately the same proportion as in the entire system. In terms of age, some of the older pipe categories were intentionally somewhat overrepresented to ensure an adequately sized sample to allow for generalizing the condition of those important older pipes.
Table 2-1: Diameter of Sewers Selected for Initial Inspections Pipe Diameter
(inches)
Number of
Pipe
Segments in
Downey
Length
(feet)
Percentage
of Entire
System
Number of
Pipe
Segments
Inspected
Length
(feet)
Percentage
Inspected
6 13 2,183 0.2% 2 415 0.8%
8 4,291 952,400 93.4% 178 46,744 90.2%
10 147 31,274 3.1% 7 1,308 2.5%
12 59 10,930 1.1% 6 1,597 3.1%
15 87 20,622 2.0% 8 1,787 3.4%
21 13 2,603 0.2% 0 0 0.0%
TOTAL 4,610 1,020,012 100.0% 201 51,851 100.0%
City of Downey Sewer Rehabilitation and
Replacement Plan
Chapter 2
Video Inspection Program
May 2023 2-2
Table 2-2: Age of Sewers Selected for Initial Inspections Year
Constructed
Number of
Pipe
Segments in
Downey
Length
(feet)
Percentage
of Entire
System
Number of
Pipe
Segments
Inspected
Length
(feet)
Percentage
Inspected
Unknown 232 52,866 5.2% 5 1,048 2.0%
1927 108 24,056 2.4% 21 5,081 9.8%
1928-1944 88 20,106 2.0% 20 4,932 9.5%
1945-1955 3,077 706,665 69.3% 116 31,213 60.2%
1956-1964 814 162,954 16.0% 24 5,902 11.4%
1965+ 291 53,366 5.25% 15 3,676 7.1%
TOTAL 4,610 1,020,012 100.0% 201 51,851 100.0%
City of Downey Sewer Rehabilitation and
Replacement Plan
Chapter 2
Video Inspection Program
May 2023 2-3
Figure 2-1: Recommended Actions for Structural Defects
City of Downey Sewer Rehabilitation and
Replacement Plan
Chapter 2
Video Inspection Program
May 2023 2-4
2.2 Inspections Performed
Before baseline inspections began, the decision was made to utilize the NASSCO Pipeline Assessment and Certification Program (PACP) Condition Grading System standards and WinCan software for data capture. Video/audio (mpeg4) and image (jpg) file formats were established and care was taken to ensure that the pipe and manhole identifiers were recorded with each inspection to allow future linkage to the City’s GIS. The City currently uses Cues, GraniteNet sewer inspection software.
The baseline inspections were performed by Downstream Services Inc. (DSI), under subcontract to the City’s consultant, RMC. Throughout the course of the inspection program, some of the selected pipes could not be inspected due to a variety of reasons, including traffic and access limitations. In addition, some pipes could not be completely inspected due to partial blockages that would not allow the camera to pass (pipes were not cleaned prior to inspection, in order to identify maintenance defects as well as structural defects). Substitute pipes were selected in those cases, located nearby and having similar size and age characteristics. Also, some of the blocked pipes were cleaned and later re-inspected.
Inspection of 205 gravity sewers with a total length of 53,241 feet was attempted in 242 runs. Of those, 179 gravity sewers, with a total length of 46,959 feet, were inspected from manhole to manhole. The reasons for the incomplete inspections included debris and/or roots that needed to be cleaned or structural defect causing pipe blockage. All such pipe segments were eventually cleaned by sewer and stormwater operations staff with adjustments made to the City’s cleaning frequency and root control programs. Any such pipe segments requirement spot repairs and/or CIPP liners have since been addressed through procurement of contractors. In all, a total of approximately 50,000 feet of sewer were inspected under the baseline assessment, including partial inspections and overlapping inspections where incomplete inspections were later completed.
2.3 Quality of Data
Videos from the first week of production during baseline inspections were reviewed on a daily basis to assess the quality of the videos and the accuracy of the operators in identifying and characterizing the defects found during the inspections. Additional videos were reviewed during the course of the baseline work. Videos and the associated databases representing approximately 6,600 feet of sewers (14% of the total quantity inspected) were critically reviewed and feedback was provided to the City and DSI. The quality of the videos and accuracy of the operator are considered very good.
There are two noteworthy issues regarding the quality of the final product developed during the quality assurance review and during subsequent assessment of the baseline data. Those issues are:
· The operator used a more conservative definition of a fracture than is commonly used so the severity of defects was overly conservative for use in the repair/rehabilitate/replace decision- making and a defect-by-defect review was required to more realistically represent the condition of the line segments. The baseline data that is presented in this report and the database used for projecting future needs has been updated to conform to the less conservative definition. · There were inconsistencies between the DSI summary reports and the databases that were delivered, and some data was missing from the database, but included in the summary reports.
These issues were resolved and corrections were made to the database to the extent possible.
City of Downey Sewer Rehabilitation and
Replacement Plan
Chapter 3
Assessment Methodology
May 2023 3-1
Chapter 3 Assessment Methodology
This chapter describes the methodology that was used during the baseline inspections and is currently used by the current video inspection program to assess the structural and maintenance condition of individual sewer lines, select the appropriate action to be taken, and prioritize and schedule those actions.
3.1 Condition Grades
Each unique observation and defect was assigned a code by the operator and recorded in an Access database via the WinCan software. The observation codes followed the NASSCO Pipeline Assessment and Certification Program (PACP) Condition Grading System standards. In addition to the nature of the defects observed, the severity of the defect was assigned a condition grade of 1 to 5 for both structural and maintenance types of defects. The condition grade indicates the importance of the defect based on the potential for further deterioration and the possible timeframe for pipe failure.
Pipe failure is defined as when the pipe can no longer convey its design capacity. The mechanisms and rates of actual pipeline deterioration will depend on local conditions, but the generalized PACP standards for condition grade definitions are shown in Table 3-1.
Table 3-1: PACP Condition Grading System
Individual Defect
Condition Grade Condition Grade Definitions
1 No or minor defects observed. Pipe failure unlikely in the foreseeable future. 2 Defects observed that have not begun to deteriorate. Pipe unlikely to fail for at least 20 years.
3 Moderate defects that will continue to deteriorate. Pipe may fail in 10 to 20 years.
4 Severe defects are present that will become Grade 5 defects within the foreseeable future. Pipe will probably fail in 5 to 10 years. 5 Pipe has failed or is likely to fail within the next 5 years. Defects require immediate attention.
3.2 Pipe Ratings
The PACP standard defines three methods for rating the condition of manhole-to-manhole pipe segments based on the individual defects found along the segment. Those methods are described in Table 3-2.
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Table 3-2: PACP Pipe Condition Ratings
Description Rating Purpose Sample Score
Pipe Segment
Score
OPR: Overall Pipe Rating
SPR: Structural Pipe
Rating
MPR: Maintenance Pipe
Rating
The rating is calculated by
multiplying the number of
occurrences of each pipe grade by
the grade and summing the
results. Computed separately for
structural and maintenance
defects. Overall rating is sum of
both.
(4*2)+(2*6) =
20 Pipe Rating Index
OPRI: Overall Pipe Rating
Index
SPRI: Structural Pipe
Rating Index
MPRI: Maintenance Pipe
Rating Index
Indicates the average defect
condition rating for all defects.
Rating indices are calculated by
dividing the total, structural, and
maintenance Segment Score by
the number of defects in each
category and rounding the result
up to the next whole number.
20 / 8
= 3
Quick Rating
QSR: Quick Structural
Rating
QMR: Quick Maintenance
Rating
Indicates the number of
occurrences for the two highest
severity grades. The order of the
numbers is highest grade, number
of occurrences of highest grade,
next-highest grade, and number of
occurrences of next-highest grade.
Letters are used for numbers
greater than 9 (A: 10-14, B: 15-19,
C: 20-24, etc.)
4226
Note: Example is based on pipe segment with: 2 defects at condition grade level 4 and 6 defects at condition grade level 2; no defects at grade levels 5, 3, or 1.
3.3 Recommended Actions for Structural Defects
Priority rankings of pipe segments and the timeframes for action are determined using the Quick Structural Rating (QSR). The QSR was selected because it focuses on the severity and the number of defects having the two highest condition grades, which are the defects that drive the need for near-term action. In particular, the QSR indicates clearly if there are a number of Grade 4 or 5 defects, which are the only defects that may need attention within the next 5 years. The other PACP condition ratings are found to be less well suited as the basis for decision making. The Structural Pipe Rating (SPR) fails to differentiate pipes that have a large number of minor defects (that do not require action in the short-term) from pipes that have a small number of major defects (which do require action). It also fails to account for differences in segment length, resulting in higher ratings in longer pipe segments than in shorter segments that are in equivalent condition. The Structural Pipe Rating Index (SPRI), which is the average condition rating for all the defects present, dilutes the importance of the more severe defects resulting in low ratings for pipe segments with a few severe defects and many minor defects.
Where the QSR indicates a pipe has one or more Grade 4 or 5 defects, the defects are further examined to determine if the pipe is likely to fail within the next 5 years. If it is judged likely to fail, the pipe is recommended for action within the next year (urgent priority) or two years (high priority). The type of action (spot repair or manhole-to-manhole rehabilitation or replacement) depends primarily on the number of spot repairs required. Sewer line segments that would need more than two spot repairs per 100 feet of pipe are further reviewed for potential manhole-to-manhole rehabilitation or replacement.
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Performing a greater number of spot repairs can in some cases be more expensive than a complete manhole-to-manhole rehabilitation.
It is assumed that spot repairs can be successfully performed on all pipes, including Generation 1 clay pipe (pre-1950). Experience in other systems indicates that attempts to complete spot repairs in these older and more fragile pipes can sometimes be problematic. The pipe can fail during the excavation process and it can require extensive additional excavation to expose competent pipe to connect to the replacement pipe. If this problem is severe enough, a complete manhole-to-manhole rehabilitation would be more cost-effective. The City will continue to evaluate this issue based on the results of spot repairs on its Generation 1 clay pipes, and make appropriate adjustments to future projects if necessary.
Generation 2 (1950-1958) and Generation 3 (post-1958) clay pipe are stronger and there is a high probability of success in completing a spot repair.
Manhole-to-manhole rehabilitation is typically performed using the lowest-cost method that is feasible in each situation. In general, trenchless technologies like pipe bursting and cured-in-place pipe (CIPP) would be employed where feasible since they are generally less costly and disruptive than the dig and replace method. However, dig and replace may be required in some situations, such as where the existing pipe has significant sagging or multiple severe offset joints.
Pipes with Grade 4 or 5 defects that are judged unlikely to fail in the next 5 years are recommended for re-inspection in 5 years. Pipes receiving spot repairs are also recommended for re-inspection in 5 years.
Pipes that are rehabilitated or replaced are scheduled for re-inspection in 10 years.
Pipes with no Grade 4 or 5 defects are unlikely to fail for at least 10 years and require only re-inspection at an appropriate interval depending on the maximum defect severity observed and the pipe generation.
The recommended intervals range from 7 to 30 years, and are be discussed further in Chapter 5 (long- term inspection program). In addition, Generation 1 pipes with Grade 3 or higher root defects in cracks and joints are reviewed are addressed and added to the chemical root control program as/if determined necessary. Figure 3-1 illustrates the decision logic described above.
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Figure 3-1: Recommended Actions for Structural Defects
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Assessment Methodology
May 2023 3-5
3.4 Recommended Actions for Maintenance Defects
Video inspections are also be used to determine appropriate actions to respond to observed maintenance defects. The intent of the maintenance recommendations is to provide the recommended maintenance method and the initial frequency that is then modified over time based on the field crew observations.
The Quick Maintenance Rating (QMR) is used as the basis to determine the pipe segments that would benefit from more frequent maintenance. The other PACP maintenance ratings suffers from the same limitations described above for the structural ratings, and are not used. The maintenance evaluation process is shown graphically in Figure 3-2. The PACP score per maintenance defect is verified to ensure the defect rating is consistent with the definitions in Table 3-3.
Figure 3-2: Recommended Actions for Maintenance Defects
Identified
Maintenance
Issues?
Maintenance
Issue Type?
Yes
Severity?
Roots
Severity?
Grease or Debris
Schedule cleaning
at maximum
interval
No
Start Here
Re-inspect in 5
years
Medium or Heavy
Chemical Root
Control
Sag > 50%
depth ?
Re-inspect in 10
yearsLight
Medium or Heavy
Eliminate Sag
Yes
Initial cleaning
frequency = 6
months
Light
Severity
No
Initial cleaning
frequency = 12
months
Heavy Medium
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Table 3-3: Maintenance Condition Ratings
Rating Debris Grease Roots PACP Score
Heavy 45% to 100% 25% to 100% 25% to 100% 4 or 5
Medium 10% to 20% 10% to 20% 10% to 20% 3
Light <15% <15% <15% 1 or 2
Clear None None None 0
Sewer cleaning is accomplished using a combination high velocity cleaning unit. The City’s current combination cleaner is used along with a trailer-mounted hydro jetter unit to allow cleaning of sewers in alleys and tight streets that cannot be reached by the combination cleaner. The procedure follows the Standard Operating Procedure included in SSMP Section IV Operations and Maintenance Program and Appendix. Routine cleaning and preventive maintenance cleaning for grease and debris is accomplished using a “Grenade Bomb”, “Chisel Point”, “Bulldog”, or “Warthog” nozzle. Mechanical root removal, when required, is accomplished using a root cutter nozzle.
Sewer line segments with moderate to severe root intrusion are recommended for treatment with root control herbicides. Roots enter through defects (e.g. failed joints, cracks) and they increase in size over time causing the existing defects to change in both nature and severity (e.g. cracks with roots progress to fractures, holes, and collapse). The application of root control herbicide stops the growth process and slows the deterioration process. Mechanical root removal is an option; however, it is not always recommended except because it is thought to potentially stimulate root growth and thereby accelerate structural deterioration of the pipe.
Grease and debris accumulate in sags. Sewer line segments with severe sags (depth of sag greater than 50% of the pipe diameter) are corrected in order to reduce the frequency of maintenance and the likelihood of a blockage and/or spill. Sags where the depth is less than 50% are be considered for potential correction depending on likelihood of failure and cost.
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Chapter 4
Inspection Results and Short-Term Projects
May 2023 4-1
Chapter 4 Inspection Results and Short-Term Projects
The assessment methodology described above was applied to all 179 completed baseline video inspections and is utilized as part of the current video inspection program. Baseline findings are presented in this chapter. Sewer line segments where the inspections are not completed, or where they are completed but require follow-up due to root intrusion or other reasons, are addressed on a regular basis as part of the sewer cleaning program.
4.1 Structural Condition
The structural conditions identified during the baseline video inspections are summarized in Table 4-1.
Of all the inspected sewers, 13 sewers (7.3 percent) warranted repair or rehabilitation at an urgent or high priority and have since been addressed. 37 sewers (21 percent) with Grade 4 or 5 defects did not require repair or rehabilitation at the time. These sewers were assigned medium priority and were re-inspected and re-assessed in 5 years.
Pipes with maximum defects less severe than Grade 4 were assigned low priority and were assigned re- inspection at intervals from 7 to 30 years depending on the defects and pipe generation, as further detailed in Chapter 5.
Table 4-1: Summary of Baseline Structural Condition Findings Priority
Recommended
Timeframe/Corrective
Action
Number of Gravity
Sewers, Inspection
Complete
Percentage of
Sewer Inspected
Urgent Repair within 1 year 3 1.7%
High Repair within 2 years 10 5.6%
Medium Re-inspect in 5 years 37 21%
Low Re-inspect in 7-30 years 129 72%
Total -- 179 100%
4.2 Maintenance Condition
Currently recommended maintenance activities and frequencies are shown for all of the City’s inspected pipe segments in Appendix A. Maintenance issues identified during the initial baseline inspections are summarized on Table 4-2 for the 179 pipe segments where the inspection was completed from manhole to manhole in order to provide an estimate of the typical maintenance findings throughout the City’s sewer system.
Table 4-2: Summary of Baseline Maintenance Condition Findings Severity Roots Grease Debris
Heavy 30 1 8
Medium 11 4 22
Light 61 153 36
Clear 77 21 113
The primary maintenance issue that identified during the baseline assessment was root intrusion with 57% of the gravity sewers inspected showing some level of root growth. This warranted the development and
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Inspection Results and Short-Term Projects
May 2023 4-2
implementation of a chemical root control program. With the frequent cracks and tight fractures observed, controlling root growth is especially significant to maintaining the longevity of the pipe.
The City has implemented a semi-annual chemical root control program with the initial 41 gravity sewers (11,800 feet) with medium to heavy root intrusion reassessed and addressed through root maintenance and/or inclusion in the root control program. As part of the program, roots are cut with a mechanical cutter approximately two months before application of the root control chemical. The chemical is most effective when applied during the hot, dry months when the roots take up the maximum dose of the herbicide. The treated sewers are re-inspected 24 months after application to evaluate the effectiveness of the program. The program is expanded as the video inspection program identifies additional sewers with significant root problems.
Roots growing in through the private laterals were observed in 72 line segments during the baseline assessment. For seven of these line segments, the only root defects were from 16 laterals. These root intrusions are capable of causing a blockage and possibly an overflow and are therefore addressed via the sewer cleaning and/or root control program. .
Grease and debris accumulation are lesser maintenance problems. There were 35 gravity sewers (12,100 feet) identified during the baseline assessment with a severity rating of medium or heavy for grease and/or debris which were either placed in the “Hotspot” cleaning program or reassessed at a later date and reassigned an appropriate cleaning frequency. Current pipe segments included in the “Hotspot” cleaning program and their associated cleaning frequency are shown in Appendix A.
Low flows were observed in 79% of the baseline gravity sewers inspected. These sewers are not expected to generate self-cleansing velocities on a daily basis, resulting in the accumulation of debris. This suggests that the City would benefit from a system-wide sewer cleaning program on a three-year frequency. The City has since implemented such a cleaning program which is completed on a regular basis in three years or less.
Vectors (cockroaches and rats) were observed in 25% of the baseline gravity sewers inspected. The City currently hires a contractor to apply pesticides on an annual basis with the entire system being addressed in three years or less. The City continues to monitor this vector control program and will modify the program as/if necessary based on future inspections.
The City ensured that all of the problems that prevented complete baseline inspections have been corrected. These included cleaning sewers, locating manholes, and correcting maps. Sewer and stormwater operations staff continue to flag any such issues that arise during its current video inspection and cleaning programs and follows up as/if necessary to address the issues discovered at that time.
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Chapter 5
Long-Term Inspection, Rehabilitation and Replacement
Program
May 2023 5-3
Chapter 5 Long-Term Inspection, Rehabilitation and
Replacement Program
The City’s initial baseline video inspection program provided a good indication of the structural and maintenance condition of the gravity sewer system, and identified several short-term rehabilitation projects and maintenance needs. Based on an analysis of this baseline sample of 5 percent of the total system footage, an estimate was made of the future rehabilitation and inspection requirements over subsequent years which have since been reassessed and implemented on a fiscal year basis. The long- term program described in this chapter provides a basis for capital program budgeting, and is updated annually as additional inspections and rehabilitation projects are performed.
5.1 Analysis of Results of Initial Inspections
Table 5-1 summarizes the recommended actions and priorities to address structural defects on the 179 manhole-to-manhole pipe segments that were inspected and assessed in 2007, differentiated by clay pipe generation. Two conclusions can be drawn with respect to the pipe generations:
· Generation 3 pipes are much more likely (64 percent) to have no defects than Generation 1 (37 percent) or Generation 2 (33 percent) pipes.
· Pipes requiring manhole-to-manhole rehabilitation or repair with urgent or high priority amount to 9 percent of Generation 1 pipes and 5 percent of Generation 2 pipes. Although 11 percent of Generation 3 pipes are in this category, this result is based on only two defective pipes due to the small sample size.
Table 5-1: Summary of Recommended Actions and Priorities by Pipe Generation Pipe Generation Urgent Priority Rehab Urgent Priority Repair High Priority Rehab High Priority Repair Medium Priority (max Grade 4/5) Low Priority (max Grade 3) Low Priority (max Grade 1 or 2) Low Priority (No Defects) Total 1 Pipe Segments 0 1 2 4 16 15 12 29 79 Percentage 0 1.3 2.6 5.1 20 19 15 37 100
2 Pipe Segments 1 1 0 2 19 18 13 27 81
Percentage 1.2 1.2 0 2.5 23 23 16 33 100
3 Pipe Segments 0 0 0 2 2 2 1 12 19
Percentage 0 0 0 11 11 11 5.2 64 100
5.2 Generalized Outcomes of Future Inspections
Based on the baseline analysis, the anticipated outcomes of future inspections of all pipes were generalized for each clay pipe generation, and are shown on Table 5-2. These percentages were based on the results of the baseline inspections, but were rounded and adjusted considering the sample sizes and engineering judgment.
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The most important assumptions were that manhole-to-manhole rehabilitation with either urgent or high priority would be required in 4 percent of Generation 1 sewers, 2 percent of Generation 2 sewers, and none of the Generation 3 sewers. Spot repairs were anticipated in 6 percent of the Generation 1 sewers, 3 percent of the Generation 2 sewers, and 5 percent of the Generation 3 sewers. Finally, medium priority Grade 4 or 5 defects (not requiring rehabilitation or repair, but to be re-inspected in 5 years) were assumed for 20 percent of Generation 1 sewers, 25 percent of Generation 2 sewers, and 10 percent of Generation 3 sewers.
Table 5-2: Generalized Outcomes of Future Inspections by Clay Pipe Generation (Percentage of inspected pipes) Pipe Generation Urgent Priority Rehab Urgent Priority Repair High Priority Rehab High Priority Repair Medium Priority (max Grade 4/5) Low Priority (max Grade 3) Low Priority (max Grade 1 or 2) Low Priority (No Defects) Total 1 1 1 3 5 20 20 15 35 100 2 1 1 1 2 25 25 15 30 100
3 0 0 0 5 10 10 10 65 100
5.3 Projected 5-Year Inspection and Rehabilitation Requirements The above-described generalized outcome model was used to estimate the initial annual sewer rehabilitation, repair and re-inspection requirements. Those annual requirements have since been modified based on the findings of the system-wide sewer cleaning program and video inspection program which have been implemented. Video inspections continue to be completed on an annual basis. Each fiscal year the latest available sewer system CCTV data collected from outside contractors and/or Sewer and Stormwater Section operations staff are analyzed. Manhole to manhole pipe segments are first sorted by those with the highest Quick Structural Rating (QSR) which focuses on severity and number of pipe defects having the two highest condition grades. CCTV data for pipe segments with the highest QSR rating are then reviewed by both Utilities Division engineering and sewer/stormwater operations staff to confirm whether such pipe segments and/or specific defects are candidates for repair/rehabilitation or can be reassessed via jetting/cleaning and CCTV at a later date to determine whether the pipe segment and/or defect has further degraded. Those pipe segments and/or defects that require repair/rehabilitation are then grouped according to the type of repair/rehabilitation determined necessary which include: spot repairs, manhole to manhole replacement, and Cured In Place Pipe (CIPP) liners. Pipe segments are then scheduled for rehabilitation or maintenance accordingly.
Re-inspections are performed based on the intervals presented in Table 5-3, which considers the results of the initial inspection (maximum grade of defects observed) and the pipe generation. In general, older pipes and pipes having more severe defects are inspected more often. Any pipe with Grade 4 or 5 defects are typically re-inspected in 5 years, included pipes that receive spot repairs. Pipes that are rehabilitated
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May 2023 5-5
or replaced from manhole-to-manhole are initially re-inspected in 10 years, with future re-inspection intervals based on observed defects.
Table 5-3: Recommended Re-inspection Intervals in Years Maximum Defect Grade from
Initial Inspection Generation 1 Generation 2 Generation 3 No Defects 15 20 30
Grade 1 or 2 10 15 20
Grade 3 7 12 15
Grade 4/5 (incl. spot repairs) 5 5 5
The annual inspection and rehabilitation/repair requirements are updated each fiscal year based on staff findings and subsequent modifications made to the recommended 5-year inspection program.
The program results in annual video inspections and repair/rehabilitation projects including: spot repairs, manhole to manhole rehabilitation/replacement, and Cured In Place Pipe (CIPP) liners as/if determined necessary based on review of the latest CCTV data..
The City assumes that sewers will continue to deteriorate over time, so that future inspections and assessments may include higher percentages of the system that need to be rehabilitated or repaired in subsequent planning periods. The City therefore anticipates that its program will grow and continue to be modified over time.
5.4 5.4 Projected Capital Costs
Planning-level construction and capital costs were estimated for inspection, rehabilitation/replacement, and repair, using the unit costs shown in Table 5-5. These unit costs were based on recent project bids and are intended to represent a long-term average cost of many projects. The inspection costs cover the cost of hiring a contractor to perform the inspections, but do not include capital costs for reviewing the inspection results and determining the appropriate action for each pipe segment, which is assumed to be performed by City staff.
The basic unit cost for rehabilitation/replacement of $130 per foot is based on the following assumptions:
· Very high percentage of projects are on small diameter (8 and 10 inch) pipes in streets with low traffic and favorable soil
· Cut and cover pipe replacement as well as trenchless technologies such as pipe bursting and CIPP are applied as determined by local conditions. The unit cost is a composite for all types of projects.
· Most manholes will not need to be replaced - minor repair and benching will be adequate. · The projects will be over a mile in length, allowing for economies of scale. · Reconnection of laterals.
Engineering costs for these projects are generally lower than for more complex construction projects.
Thus, multipliers of 8% rather than the more customary 10% were applied to construction costs to compute design and construction engineering costs.
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Table 5-4: Unit Costs for Video Inspection and Rehabilitation Item Description
Spot Repair
(cost per
repair)
Rehabilitation/
Replacement
(cost per LF)
Video Inspection
(cost per LF)
Construction Cost $7,000 $130 $1.10
Legal/Administrative
(5% of construction cost) $350 $7
Design
(8% of construction cost) $560 $10
Engineering Services during
Construction
(8% of construction cost) $560 $10
Total Capital Cost $8,470 $157 $1.10
The cost per spot repair was converted to a cost of $37 per linear foot, assuming one spot repair per typical 230-foot manhole-to-manhole section. The resulting annual capital costs are shown in Table 5-5.
Table 5-5: Annual Inspection and Rehabilitation/Replacement/Repair Costs Program
FY
2023/24
FY
2024/25
FY
2025/26
FY
2026/27
FY
2027/28 Totals
Sewer Main Rehabilitation and
Repair Program 1,000,000 900,000 1,000,000 1,000,000 1,000,000 4,900,000 Sewer Video Assessment 400,000 400,000 --- --- --- 800,000 Totals 1,400,000 1,300,000 1,000,000 1,000,000 1,000,000 5,700,000
As the program proceeds, the projections are refined and the capital cost projections updated to reflect the latest findings and also the actual unit costs from the latest projects. Annual capital cost requirements depend on the findings of subsequent re-inspections, which depend on the extent to which the pipes deteriorate over time.
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Chapter 6
Summary of Findings and Recommendations
May 2023 6-1
Chapter 6 Summary of Findings and Recommendations
6.1 Structural Condition
The structural condition of the City’s sanitary sewer system, considering the age and materials of construction, is generally good. Nevertheless, a number of gravity sewers inspected continue to warrant repair or rehabilitation. The structural issues observed to date can and are corrected using spot repairs, cut and cover pipe replacement, or in-situ rehabilitation technologies such as CIPP or pipe bursting.
6.2 Maintenance Condition
The City should has implemented an aggressive preventive maintenance program, particularly to deal with the root intrusion that has been observed during the video inspections. Semi-annual chemical root control and “Hotspot” cleaning of the problem sewers on a frequency up to four times per year have been implemented and such programs modified as necessary each year. The current maintenance activities and initial frequencies are shown in Appendix A and B.
Over two-thirds of the gravity sewers inspected had low flows at the time of the baseline inspections. The City has since implemented a system-wide cleaning program on a three-year frequency to maintain the maximum hydraulic capacity of its sanitary sewer system. Cleaning frequencies are adjusted for each pipe based on findings during subsequent cleanings.
Vectors were observed in nearly one-quarter of the baseline gravity sewers inspected. The City has therefore implemented an annual vector control program and considers changes based on each year’s inspections.
Finally, the City ensures that all of the problems that prevent complete inspections are followed up with subsequent inspections and appropriate rehabilitation implemented as/if determined necessary.
6.3 Long-Term Inspection and Rehabilitation and Replacement Program
While the condition of the gravity sewers that inspected to date have been found to be generally good, the frequency of problems observed during this inspection effort warranted implementation of an annual video inspection program.
This inspection effort and future inspections helps identify defects in gravity sewers that did not require correction at the time they were initially inspected. The City continuing to re-inspect defects periodically to identify the rate of progression of the structural defects. The City use this data to act in a timely manner when corrective action is warranted.
The CIP budget is reviewed annually and adjusted based on the results of the ongoing video inspections and the actual costs of the rehabilitation and replacement projects.
May 2023 A
Appendix A - Hotspot Cleaning List
City of Downey Sewer Rehabilitation and
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Appendix A
Hotspot Cleaning List
May 2023 A
ID
Area Location Length (ft)
1 79 Brookpark Rd & Samoline Ave, MH9 to MH3 (584ft) West 584 2 79 W/S Paramount Blvd & S/S of 5Fwy at Off Ramp, MH23 to MH9 (630ft) / MH23 East to MH22 (400ft)
400
3 80 Parrot Ave & Brookpark Rd, MH58 to MH45 (420ft) / MH58 to MH56 (210ft)
630
4 111 Telegraph Rd & Passions Blvd, Service Rd - MH22 to MH34 (308ft) / MH22 to MH26 (270ft) / On Teleg - MH21 to MH22 (55ft)
633
5 111 Telegraph Rd & Hasty Ave, MH17 to MH23 (210ft) South 210 6 109 Gallatin Rd & Lakewood Blvd, MH9 to MH8 (625 ft) / MH14 to MH9 (350ft)
975
7 92 Old River School Rd & Florence Ave, MH40 to MH45 (300ft) 300 8 117
&
107
10304 Paramount Blvd, MH25 to MH55 (545ft)
545
9 140 Downey Sanford Bridge Rd & Florence Ave, Siphon - MH14 North to MH13 (65ft) / MH13 to MH4 (300ft)
365
10 141 Newville Ave & Florence Ave, Siphon - MH29 to MH27 (65ft) 65 11 141
&
140
Pangborn Ave & Florence Ave to County Line, MH11 to MH10 (600ft) / MH11 to MH33 (600ft)
1,200
12 141 10051 Mattock Ave, MH25 to MH18 (305ft) 305
13 137 11016 New St, MH48 East to MH43 (144ft) 144
14 126
&
136
On Myrtle St from 5th St to Firestone Blvd, MH19 East to MH66 (256ft) / Siphon - MH19 to MH# UNKN (50ft)
306
15 126 4th St & Myrtle St, MH25 North to MH19 (271ft) 271 16 136 3rd St & Myrtle St, MH3 North to MH25 (530ft)
17 136 11016 Myrtle St, MH8 North to MH3 (180ft) / MH8 West to MH50 (390ft)
570
18 136 2nd St & Myrtle St, MH16 North to MH8 (200ft) 200 19 136 Behind 8041 Firestone in Alley Enter at Myrtle St, MH19 West to MH31 (390ft) / MH19 North to MH16 (200ft)
590
20 136* Paramount Blvd & Firestone Blvd, MH35 West to MH50 (650ft) / MH35 North to MH27 (350ft)
1,000
21 147
Embassy Suites on Firestone Blvd, MH11 to MH4 (325ft) / MH12 to MH11 (68ft) / MH# to MH12 (13ft) / MH46 to MH# (200ft) / MH44 to MH46 (60ft)
666
22 148* Lakewood Blvd & Firestone Blvd, MH35 West to MH40 (515ft) 515 23 159 Woodruff Ave & Firestone Blvd, MH40 to MH45 (300ft) 300 24 145 7862 Brookmill Rd, MH13 to MH7 (690ft) 690
25 144 Stewart & Gray Rd & Rives Ave, MH15 to MH61 (350ft) / MH15 to MH59 (350ft) / MH14 to MH15 (30ft)
380
26 157 Patton Rd & Cleta St, MH19 to MH6 (284ft) 284
27 155 Paramount Blvd & Alameda St, MH73 to MH57 (680ft) 680
City of Downey Sewer Rehabilitation and
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Appendix A
Hotspot Cleaning List
May 2023 A
ID
Area Location Length (ft)
28 165 Rives Ave & Quill Dr, MH45 to MH39 (280ft) / MH46 to MH45 (30ft) 310 29 166 On Alameda St from Paramount Blvd to Downey Ave, MH73 to MH16 (1,565ft)
1,565
30 177 Alley S/O Imperial Hwy E/O Paramount Blvd, MH37 to MH40 (333ft) / MH37 to MH22 (350ft) / Reverse Flush - MH37 to MH49 (275ft) 958
31 191 8039 Adoree St, MH38 North to MH49 (555ft) / MH38 East to MH34 (257ft)
812
32 190 Gardendale St & Paramount Blvd, MH31 to MH12 (660ft) 660 33 206
Downey Ave & Gardendale St, MH40 East to MH# (15ft) / MH# East to 8329 Gardendale St (325ft) / Reverse Flush - MH40 West to MH# (50ft)
390
34 192 Brookshire Ave & Imperial Hwy, MH28 to MH41 (400ft) / MH28 to MH58 (660ft) / MH27 East to MH28 (100ft)
1160
35 192
N/O Imperial Hwy & Verdura Ave, MH14 West to MH15 (300ft) / MH14 South to MH21 (100ft) / Southside Imperial Hwy - MH21 to MH27 (600ft) / MH21 to MH44 (490ft)
1,490
36 168 12102 Marbel Ave, MH9 to MH57 (713ft) S/O Cavel MH9 to MH8 (32ft) / Reverse Flush
745
37 180 Marbel Ave & Alameda St, MH10 to MH8 (668ft) 668 38 195 Imperial Hwy & Bellflower Blvd S/E Corner, MH33 to MH29 (328ft) 328 39 195 9530 Imperial Hwy, MH29 to MH30 (15ft)
40 195 Imperial Hwy & Dunrobin Ave, MH# West to MH21 (600ft) / MH13 West to MH# (50ft) / MH13 to MH10 (275ft)
925
41 196 12310 Woodruff Ave, Service Rd - MH10 East to MH8 (690ft) 690 42 211 Faust Ave & Laurelwood Ln, MH24 to MH16 (300ft) / E/O Faust Ave MH16 to MH11 (350ft)
650
43 148 9021 Firestone Blvd. East of Lakewood Blvd MH 30 to MH29 (175') (Acapulco Restaurant)
175
44 168 Alley Behind 11837 Lakewood Blvd MH 31 to MH 33 - ( 95') 95
* The noted cells represent locations that are maintained overnight due to the heavy traffic on those streets.
May 2023 B
Appendix B - Root Control List
City of Downey Sewer Rehabilitation and
Replacement Plan
Appendix B
Root Control List
May 2023 B
ID Area Location Length (ft)
1 63 Bangle Rd (between Guatemala Ave & 7866 Bangle
Rd) MH N0559 - MH N0554, 685.93ft 685
2 63 Alderdale St (between 7837 Alderdale St & Botany
St) MH N0053 - MH N0460, 775ft 775
3 63 Botany St (between 7706 Botany St & Smallwood
Ave) MH N0543 - MH N0460, 752ft 752
4 63 Danvers St (between 7706 Danvers St & Smallwood
Ave) MH N0558 - MH N0459, 902ft 920
5 62,
63, 79
Bairnsdale St (between 7706 Bairnsdale St &
Smallwood Ave) MH N2081 - MH N0458, 1,050ft 1,050
6 63, 79 Smallwood Ave (between Bairnsdale St & Botanny St) MH N0458 - MH N0460, 545ft 545
7 62,
63, 79
Allengrove St (between Guatemala Ave & Tweedy
Ln) MH N2398 - MH N0464, 1565.28ft 1,565
8 78 Coolgrove Dr (between 7606 Coolgrove Dr & Horley
Ave) MH N1922 - MH N1920, 570ft 570
9 78 Shadyoak Dr (between 7606 Shadyoak Dr & Horley
Ave) MH N2113 - MH N2110, 725ft 725
10 78 Finevale Dr (between 7506 Finevale Dr & Horley Ave) MH N2118 - MH N2122, 787ft 787
11 78 Calmcrest Dr (between 7506 Calmcrest Dr & Horley
Ave) MH N2105 - MH N2101, 1,200ft 1,200
12 77 Ivo St (between Guatemala Ave & Norlain Ave) MH
N2167 - MH N2230, 340.22ft 340
13 77, 93 Norlain Ave (between Ivo St & Lubec St) MH N2230 - MH N2228, 521.68ft 521
14 96,
109
Manzanar Ave (between 9117 Manzanar Ave &
Gallatin Rd) MH N0131 - MH N0522, 994.88ft 995
15 110 Arrington Ave (between 9129 Arrington Rd & Gallatin Rd) MH N0345 - MH N0342, 909.84ft 910
16 110
120
Haledon Rd(Between 9102 Haledon & Appleby St)
MH N0205 - MH N0352 801.33 FT
801
City of Downey Sewer Rehabilitation and
Replacement Plan
Appendix B
Root Control List
May 2023 B
17 120 Appleby St (between 9339 Appleby St & Lemoran
Ave) MH N0821 - MH N0800, 391.73ft 392
18 130 Otto St (between 9217 Otto St & Garnish Dr) MH
N0927 - MH N0926, 240ft 240
19 130 Garnish Dr (between N Otto St & S Otto St) MH
N0926 - MH N0925, 138ft 138
20 118 Dolan Ave (between 9914 Dolan Ave & Dinsdale St) MH N0262 - MH N1046, 590ft 590
21 160 Buell St (between 9514 Buell St & Lesterford Ave) MH N1839 - MH N1836, 813ft 813
22 92 Irwingrove Dr (between Sherry Ave & Alley) MH
N2301 - MH N2298, 1058.86ft 1,058
23 135 Brookmill Rd (between 7733 Brookmill Rd & 7621
Brookmill Rd) MH N2847 - MH N2514, 686ft 686
24 145 Cleta St (between 7986 Cleta St & Pruess Ave) MH N2604 - MH 2601, 634ft 634
25 145 Rives Ave (between Benares St & Luxor St) MH
N2598 - MH N1526, 450ft 450
26 211 Laurelwood Ln (between 10260 Laurelwood Ln &
10228 Laurelwood Ln) MH N4031 - MH N4030, 350ft 350
27 196
12321 Woodruff Ave, Service Road (between
Woodruff Ave & MH N4198) MH N3942 - MH N4198,
929ft
929
28 211 Branscomb St (between 10263 Branscomb St &
Carfax Ave) MH N4019 - MH N4014, 345ft 345
29 225 Carfax Ave (between Priscila St & Branscomb St) MH N4008 - MH N 4014, 259ft 259
Appendix
C Sanitary Sewer Facilities Design Guidelines, Policies, and Procedures
City of Downey
Sanitary Sewer Facilities Design
Guidelines, Policies, and
Procedures
Prepared by:
May 2023
City of Downey Sanitary Sewer Design Guidelines, Policies, and Procedures
May 2023
Table of Contents
CHAPTER 1 INTRODUCTION ..................................................................................................................... 1-1
1.1 DEFINITIONS ............................................................................................................................................... 1-1
CHAPTER 2 PERMITS, FEES, AND INSPECTION PROCEDURE ........................................................ 2-1
2.1 PERMIT APPLICATION ................................................................................................................................. 2-1
2.1.1 Tapping a Sewer Main ................................................................................................................ 2-1
2.1.2 Connecting to County Sewer ....................................................................................................... 2-1
2.2 INDUSTRIAL WASTE PERMIT ....................................................................................................................... 2-1
2.2.1 Industrial Waste Permit Application ........................................................................................... 2-2
2.2.2 Change of Permit Restrictions .................................................................................................... 2-2
2.2.3 Revocation of Industrial Waste Permit ....................................................................................... 2-2
2.2.4 Prohibited Industrial Waste Discharges ..................................................................................... 2-2
2.3 FEES ........................................................................................................................................................... 2-3
2.3.1 Refund of Fees ............................................................................................................................. 2-3
2.3.2 Connection Fees .......................................................................................................................... 2-3
2.3.3 Industrial Permit Fee .................................................................................................................. 2-4
2.3.4 Plan Checking Fee ...................................................................................................................... 2-4
2.3.5 Sewer Easement Processing Fee ................................................................................................. 2-4
2.3.6 Encroachment Permit Processing Fee ........................................................................................ 2-4
2.3.7 Inspection Fee ............................................................................................................................. 2-4
2.3.8 Lateral Connection Fee .............................................................................................................. 2-5
2.4 INSPECTION ................................................................................................................................................ 2-5
2.4.1 Maintenance Inspections ............................................................................................................. 2-5
2.4.2 Inspection of New Construction .................................................................................................. 2-5
2.5 PROJECT COMPLETION ................................................................................................................................ 2-5
2.5.1 Certificate of Final Inspection .................................................................................................... 2-5
2.5.2 Record Drawings ........................................................................................................................ 2-6
2.5.3 Sewer Dedication Requirements ................................................................................................. 2-6
2.5.4 Warranty Period ......................................................................................................................... 2-6
2.6 SEWER EASEMENT REQUIREMENTS ............................................................................................................ 2-6
CHAPTER 3 STANDARDS OF DESIGN FOR SEWERS........................................................................... 3-1
3.1 ESTIMATING FLOW RATE............................................................................................................................ 3-1
3.1.1 Average Flow Rate ...................................................................................................................... 3-1
3.1.2 Peak Flow Rate ........................................................................................................................... 3-3
3.2 SIZING SEWER MAINS ................................................................................................................................. 3-3
3.2.1 Minimum Diameter ..................................................................................................................... 3-3
3.2.2 Slope ............................................................................................................................................ 3-3
3.2.3 Pipeline Size Criteria .................................................................................................................. 3-4
3.3 PIPELINE SEPARATION ................................................................................................................................ 3-5
3.4 MINIMUM DEPTH OF SEWER ....................................................................................................................... 3-5
3.5 SEWER ALIGNMENT .................................................................................................................................... 3-5
3.5.1 Change in Direction at Manholes ............................................................................................... 3-5
3.5.2 Easements ................................................................................................................................... 3-5
3.5.3 Utility Crossings ......................................................................................................................... 3-5
3.5.4 Horizontal Curves ....................................................................................................................... 3-5
3.6 MANHOLES ................................................................................................................................................. 3-5
3.6.1 Drop Manholes ........................................................................................................................... 3-6
3.6.2 Diameter ..................................................................................................................................... 3-6
City of Downey Sanitary Sewer Design Guidelines, Policies, and Procedures
May 2023
3.6.3 Flow Channel .............................................................................................................................. 3-6
3.6.4 Bench .......................................................................................................................................... 3-6
3.7 LATERALS................................................................................................................................................... 3-6
3.8 SUBSTRUCTURES ........................................................................................................................................ 3-6
3.9 SOIL CONDITIONS ....................................................................................................................................... 3-6
3.10 BENCH MARKS ........................................................................................................................................... 3-7
3.11 SEWER SERVICE FOR LARGE PARCELS ........................................................................................................ 3-7
3.12 CONSTRUCTION MATERIALS....................................................................................................................... 3-7
3.12.1 Sewer Pipes ................................................................................................................................. 3-7
3.13 CONSTRUCTION METHODS ......................................................................................................................... 3-7
3.13.1 Excavations ................................................................................................................................. 3-8
3.13.2 Wet or Soft Ground ..................................................................................................................... 3-8
3.13.3 Avoidance of Trees ...................................................................................................................... 3-8
3.13.4 Sewer under other Structures ...................................................................................................... 3-8
3.13.5 Shallow Sewers ........................................................................................................................... 3-8
3.13.6 Placing Vitrified Clay Pipe ......................................................................................................... 3-8
3.13.7 Laying Pipe ................................................................................................................................. 3-8
3.13.8 Tapping Public Sewer ................................................................................................................. 3-8
3.13.9 Work Shall be Watertight ............................................................................................................ 3-8
3.13.10 Disposal of Excavated Materials ............................................................................................ 3-9
3.13.11 Traffic Control ........................................................................................................................ 3-9
3.14 LIFT STATIONS ........................................................................................................................................... 3-9
3.14.1 Pumps .......................................................................................................................................... 3-9
3.14.2 Piping and Appurtenances ........................................................................................................ 3-10
3.14.3 Controls .................................................................................................................................... 3-10
3.14.4 Alarms ....................................................................................................................................... 3-10
3.14.5 Dry Well .................................................................................................................................... 3-10
3.14.6 Wet Well .................................................................................................................................... 3-10
3.14.7 Operations and Maintenance .................................................................................................... 3-11
3.15 FORCE MAINS ........................................................................................................................................... 3-11
3.15.1 Velocity and Diameter .............................................................................................................. 3-11
3.15.2 Appurtenances ........................................................................................................................... 3-11
3.15.3 Termination ............................................................................................................................... 3-11
3.15.4 Pipe and Design Pressure ......................................................................................................... 3-11
CHAPTER 4 PIPE REHABILITATION ....................................................................................................... 4-1
4.1 DEFINITIONS ............................................................................................................................................... 4-1
4.2 INSPECTION ................................................................................................................................................ 4-2
4.3 PLANNING ................................................................................................................................................... 4-2
4.4 PREPARATION ............................................................................................................................................. 4-2
4.4.1 Cleaning ...................................................................................................................................... 4-2
4.4.2 Temporary Service Connections ................................................................................................. 4-3
4.4.3 Bypass Requirements .................................................................................................................. 4-3
4.5 EXECUTION ................................................................................................................................................. 4-4
4.5.1 Inspection .................................................................................................................................... 4-4
4.5.2 Service Reconnection .................................................................................................................. 4-4
4.5.3 Post Repair CCTV ....................................................................................................................... 4-4
4.6 PIPE BURSTING ........................................................................................................................................... 4-4
4.7 CURED-IN-PLACE PIPE ............................................................................................................................... 4-6
CHAPTER 5 TECHNICAL SPECIFICATIONS .......................................................................................... 5-1
City of Downey Sanitary Sewer Design Guidelines, Policies, and Procedures
May 2023
CHAPTER 6 STANDARD DRAWINGS ....................................................................................................... 6-1 · 1-S STANDARD SEWER NOTES FOR CONSTRUCTION
· 2-S STANDARD SANITARY SEWER MATERIALS
· 3-S STANDARD SEWER LEGEND AND ABBREVIATIONS
· 4-S SAMPLE TITLE BLOCK FOR CONSTRUCTION DRAWINGS
· 5-S SANITARY SEWER TRENCH AND PAVING
List of Tables
TABLE 3-1: EDU FLOW FACTORS....................................................................................................................... 3-2 TABLE 3-2: PEAKING FACTORS.......................................................................................................................... 3-3 TABLE 3-3: MINIMUM PIPELINE SLOPES ......................................................................................................... 3-4 TABLE 3-4: DEPTH OF FLOW ............................................................................................................................... 3-4 TABLE 4-1: APPLICABILITY OF REHABILITATION METHOD FOR SPECIFIED DEFECTS ...................... 4-3 TABLE 4-2: PIPE BURSTING CLASSIFICATIONS ............................................................................................. 4-4 TABLE 5-1: CITY STANDARD SPECIFICATIONS INDEX ................................................................................ 5-1 TABLE 6-1: STANDARD DRAWING INDEX ....................................................................................................... 6-1
List of Appendices
APPENDIX A - PERMIT APPLICATION FORMS
· CITY OF DOWNEY PUBLIC WORKS ENCROACHMENT PERMIT
· CITY OF DOWNEY BUILDING & SAFETY PERMIT APPLICATION
· LACSD SEWER CONNECTION APPLICATION
· LACSD DISTRICT NO. 2 SEWER CONNECTION FEES
· LACSD DISTRICT NO. 18 SEWER CONNECTION FEES
· LACSD INDUSTRIAL WASTEWATER DISCHARGE PERMIT APPLICATION · LACSD INDUSTRIAL WASTEWATER DISCHARGE PERMIT APPLICATION – FORM A · LACSD INDUSTRIAL WASTEWATER DISCHARGE PERMIT APPLICATION – FORM B · LACSD INDUSTRIAL WASTEWATER DISCHARGE PERMIT APPLICATION – FORM C · LACSD INDUSTRIAL WASTEWATER DISCHARGE PERMIT APPLICATION – FORM D
APPENDIX B - CITY STANDARD SPECIFICATIONS
· 01010 SUMMARY OF WORK
· 01025 MEASUREMENT AND PAYMENT
· 01100 STORMWATER RUNOFF
· 01200 CONSTRUCTION SURVEYING
· 01570 TRAFFIC CONTROL
· 01600 MATERIAL AND EQUIPMENT
· 01650 MOBILIZATION
· 02050 EQUIPMENT, PIPING, AND MATERIALS DEMOLITION
· 02060 MAINTENANCE OF EXISTING UTILITIES
· 02210 PCC REMOVALS
· 02215 EXCAVATION AND BACKFILL
· 02220 STRUCTURE EARTHWORK
· 02750 ASPHALT CONCRETE AND PORTLAND CEMENT CONCRETE PAVEMENT · 02763 TRAFFIC STRIPING
· 03000 CONCRETE
· 03201 CONCRETE REINFORCEMENT
· 03260 CONCRETE JOINTS AND WATERSTOPS
· 03300 BELOW GRADE CONCRETE STRUCTURES
· 03345 CONCRETE FINISHING, CURING, AND WATERPROOFING
City of Downey Sanitary Sewer Design Guidelines, Policies, and Procedures
May 2023
· 03393 CONCRETE SEALER AND HARDENER
· 03461 PRECAST REINFORCED CONCRETE MANHOLES AND MANHOLE BASES · 08300 SEALANTS AND CAULKING
· 09880 POLYVINYL CHLORIDE PLASTIC LINERS FOR WET WELL AND OVERFLOW
MANHOLE
· 11000 EQUIPMENT GENERAL PROVISIONS
· 11060 PUMPING EQUIPMENT
· 11100 TESTING AND STARTUP
· 11200 STRUCTURAL STEEL AND MISCELLANEOUS METALWORK
· 11300 BASIC MATERIALS AND METHODS
· 11400 PRECAST REINFORCED CONCRETE MANHOLES AND MANHOLE BASES · 11500 WELLWASHER USA SYSTEM
· 11600 HATCH DOORS
· 14043 LEAKAGE AND INFILTRATION TESTING OF NON-PRESSURE PIPELINES · 14050 FORCE MAIN POLYVINYL CHLORIDE (PVC) PIPE
· 14058 INSTALLATION OF GRAVITY SEWER PIPELINES
· 14059 VITRIFIED CLAY PIPE AND ASSOCIATED MATERIALS
· 14100 EXISTING FACILITIES
· 14101 COORDINATION AND PROJECT REQUIREMENTS
· 14102 PROJECT RECORD DOCUMENTS AND CONTRACT CLOSEOUT
· 14103 CONSTRUCTION FACILITIES, TEMPORARY CONTROLS, AND SIGNS · 14104 CLEARING, GRUBBING, AND RESTORATION
· 14105 TRENCHING, BACKFILLING, AND COMPACTING
· 14107 PRESSURE TESTING OF FORCE MAIN
· 14108 INSTALLATION OF PRESSURE PIPELINES
· 14111 VALVES
· 14113 QUALITY CONTROL AND TESTING LABORATORY SERVICES · 14114 CURED-IN-PLACE PIPE
· 16050 BASIC ELECTRICAL MATERIALS AND METHODS
· 16110 RACEWAYS
· 16120 CONDUCTORS
· 16195 ELECTRICAL IDENTIFICATION
· 16450 GROUNDING
· 16480 MOTOR CONTROL CENTERS
· 16500 LIGHTING
· 16600 30 KVA STEP DOWN TRANSFORMER
·
APPENDIX C - GREENBOOK STANDARD DRAWINGS
· 200-4 PRECAST CONCRETE SEWER MANHOLE
· 201-3 PRECAST CONCRETE SHALLOW MANHOLE
· 202-2 DROP SEWER MANHOLE
· 204-3 TERMINAL CLEANOUT STRUCTURE
· 205-3 SEWER MANHOLE ADJUSTMENT
· 206-2 MANHOLE RAISING RINGS
· 207-3 PRECAST REINFORCED CONCRETE MANHOLE BASE
· 208-3 BREAKING INTO EXISTING MANHOLES
· 210-4 24” MANHOLE FRAME AND COVER (LOCKING TYPE)
· 211-3 MANHOLE FRAME AND COVER (PRESSURE TYPE)
· 212-3 ANCHOR SYSTEM FOR PRESSURE COVER
· 220-4 CHIMNEYS
· 221-2 PIPE ANCHORS AND BACKFILL STABILIZERS
· 222-2 HOUSE CONNECTION SEWER (SEWER LATERAL)
City of Downey Sanitary Sewer Design Guidelines, Policies, and Procedures
May 2023
· 223-3 HOUSE CONNECTION REMODELING
· 224-3 SUPPORTS FOR CONDUITS ACROSS TRENCHES
· 225-3 BLANKET PROTECTION FOR PIPES
· 630-5 600 MM (24”) MANHOLE FRAME AND COVER
· 636-3 POLYPROPYLENE PLASTIC STEP
City of Downey Sanitary Sewer Design Guidelines, Policies, and Procedures
May 2023
List of Abbreviations
APWA American Public Works Association
ASTM The American Society for Testing Materials
AWWA American Water Works Association
CAD Computer-Aiding Drafting (AutoCAD)
C.E. Civil Engineer
CIP Capital Improvement Program
CCTV Closed Circuit Television
CFP Close-Fit Pipe
CFR Carbon Fiber Relining
CIPP Cured In Place Pipe
CML Cement Mortar Lining
CO Clean out
LACSD Los Angeles County Sanitation Districts
d/D Depth over Diameter (pipe)
DIP Ductile Iron Pipe
EDU Equivalent Dwelling Unit
fps Feet per second
FOG Fats, Oils, or Grease
gpd Gallons per Day
GIS Geographic Information System
Greenbook Standard Specifications for Public Works Construction – Latest Edition H2S Hydrogen sulfide
HDPE High Density Polyethylene
LEL Lower explosive limit
MSL Modified Slip Lining
NAD North American Datum
NASSCO National Association of Sewer Service Companies
NCPI National Clay Pipe Institute
NPSH Net Positive Suction Head
PACP Pipeline Assessment and Certification Program
PB Pipe bursting
PE Polyethylene
City of Downey Sanitary Sewer Design Guidelines, Policies, and Procedures
May 2023
pH Measure of the acidity or basicity of a solution
PR Pipe removal
PSI Pounds per square inch (pressure)
PVC Polyvinyl Chloride
RPM Revolutions per minute
SCADA Supervisory Control and Data Acquisition
SL Slip lining
TDH Total Dynamic Head
ThP Thermoformed Pipe
UCL Underground Coatings and Linings
VCP Vitrified Clay Pipe
City of Downey Sanitary Sewer Design Guidelines, Policies, and Procedures Executive Summary
May 2023 i
Executive Summary
The City of Downey’s Sanitary Sewer Facilities Design Guidelines, Policies, and Procedures shall be used for planning, design, construction, and acceptance of sanitary sewer collection system facilities within the City of Downey (City or Downey). All City or private development improvement plans prepared as part of a Capital Improvement Program (CIP), development, or rehabilitation/replacement project that includes sewer facilities within Downey shall adhere to the guidelines in this document.
Formal correspondence may be addressed to:
City of Downey, Department of Public Works
11111 Brookshire Avenue
Downey, CA 90241-7016
562-904-7110 (phone)
562-904-7296 (fax)
All sanitary sewer improvement plans within the City shall include an approval block with wet stamp and signature by a licensed civil engineer (C.E.) registered in the State of California and signature and registered C.E. license number of the City Director of Public Works or an authorized representative. The project review and approval procedures, as outlined in this document, shall be followed.
City of Downey Sanitary Sewer Design Guidelines, Policies, and Procedures
May 2023 1-1
Chapter 1 Introduction
These procedural guidelines are intended to provide developers and City staff with concise procedures and guidance for the processing of privately constructed sanitary sewer improvement projects and for the development of projects under the City’s Capital Improvement Program. The Director of Public Works, or an authorized representative, shall administer, implement, and enforce the provisions of this document.
Any powers granted to or duties imposed upon the Director of Public Works may be delegated to persons in the employ of the City.
This document does not substitute for regulations and requirements of other public agencies, including the sanitary sewer facilities owned and operated by the Los Angeles County Sanitation Districts (LACSD) or other adjacent City and County agencies.
1.1 Definitions
The following words are defined in this section and are in addition to the definitions specified in the latest edition of the “Greenbook”, Standard Specifications for Public Works Construction.
Acceptance – The action by the City accepting ownership of sewer facilities constructed in accordance with this document.
Approved Plans – Construction drawings that were reviewed and signed by the Director of Public Works or an authorized representative
Approved Equal – A material or product that exceeds or is equivalent to, in the opinion of the Director of Public Works or an authorized representative, in all respects to a product which is specified.
Appurtenances – Valves, pumps, piping, fittings, cleanouts, manholes, frames and covers, lateral markers, and all other objects required to make a complete sanitary sewer installation.
Cesspool – A lined excavation which receives the discharge of a sanitary sewer drainage system or part thereof, designed to retain organic matter and solids, but permitting liquids to seep through the bottom and sides.
Chimney – A vertical section of a lateral extending either from a vertical tee on the main line or from a long radius ninety degree (90°) bend set vertically at the curb or property line, and reinforced with concrete.
Collection System – Facilities used for collecting, conveying, pumping, treating, and disposing of sewage.
Dedication – The process by which sewer facilities are approved and accepted by City Council thereby becoming a public sewer owned and maintained by the City.
Discharger – A person or entity that discharges or causes a discharge to a public sewer.
Design Engineer - A licensed professional engineer registered in the State of California hired by the City or developer for the design of the proposed work. Also Engineer of Record.
Domestic Sewage – The waterborne waste produced from non-commercial or non-industrial activities along with those which result from normal human living processes.
Effluent – The liquid outflow from a treatment plant or facility constructed and operated for the treatment of sewage or industrial waste.
Final Acceptance – The formal action by the City accepting the work as fully completed, in accordance with these requirements.
City of Downey Sanitary Sewer Design Guidelines, Policies, and Procedures
May 2023 1-2
Industrial Building – A building, structure, or works which is used or designed to be used for the manufacturing, processing, or distribution of materials, equipment, supplies, food, or commodities of any description; or which is designed to be used, as a school, sanitarium, hospital, penal institution, or charitable institution.
Industrial Waste – Waste substances, liquid or solid, including explosive, noxious, or toxic gases when present in the sewerage system.
Industrial Wastewater – Waterborne wastes and wastewater, excluding domestic sewage and uncontaminated water, including wastewater from any producing, manufacturing, processing, institutional, commercial, agricultural, or other operation where the wastewater discharged includes significant quantities of wastes of nonhuman origin.
Inspector – A person authorized by and representative of the Director of Public Works or an authorized representative to inspect wastewater generation, conveyance, storage, processing, and disposal facilities.
Interceptor – A facility designed, constructed, and operated for the purpose of removing and retaining dangerous, deleterious, or prohibited constituents from wastewater by differential gravity separation before discharge to the public sewer.
Lateral – The sewer pipeline from the plumbing of a building to the collection main. This includes both the portion of the sewer piping within the street or right-of-way which extends from the property or sewer right-of-way line to a connection with the sewer main for the purpose of conveying domestic sewage (lower lateral) and that portion of the onsite (upper lateral) sewer piping between the property or sewer right-of-way line to the plumbing of a building.
Licensed Contractor – The person or entities entering into a contract with the City or private developer for performance of the work or improvement. The contractor shall have a valid and active State of California Contractor’s License issued pursuant to Chapter 9, Division 3, of the Business and Professions Code, State of California in the Classification of A, “General Engineering Contractor,” C-34 “Pipeline Contractor,” or C-42 “Sanitation System Contractor.”
Lift Station – A facility designed and constructed to raise sewage from a lower to a higher elevation or to overcome head losses due to pipeline friction. Also Pump Station.
Lot – A piece or parcel of land bounded, defined, or shown upon a plat or deed recorded in the office of the County Recorder of Los Angeles County, which conforms to the boundaries of such lot as shown upon such recorded map, plat, or deed. In the event any building or structure covers more area than a lot the term lot shall include all such pieces or parcels of land upon which said building or structure is wholly or partly located together with the yards, courts, and other unoccupied spaces legally required for the building or structure.
Permittee – A person to whom a permit has been issued pursuant to the provisions of this document and City Municipal Code.
Public Sewer – A sanitary sewer dedicated to public use and whose use and operation are controlled by a public corporation by means of appropriate easements.
Saddle – Wye saddle means a short pipe fitting with a shoulder at one end to allow the application of the fitting to a hole tapped in the sewer main such that the short pipe shall form a forty-five degree angle from the center of the sewer main pipe.
Tee saddle means a short pipe fitting with a shoulder at one end to allow the application of the fitting to a hole tapped in the sewer main such that the short pipe shall form a ninety degree angle from the center of the sewer main pipe.
Seepage Pit – A lined excavation in the ground which receives the discharge of a septic tank, so designed as to permit the liquid portion of the wastewater from the septic tank to seep through its bottom and sides.
City of Downey Sanitary Sewer Design Guidelines, Policies, and Procedures
May 2023 1-3
Septic Tank – A receptacle which receives the discharge from a sanitary sewer system, so designed and constructed as to retain solids, digest organic matter through a period of detention, and allow the liquids to discharge into the soil outside of the tank through a drain field system or one or more seepage pits.
Sewage – Waterborne or liquid wastes, including domestic sewage and industrial waste, but does not include or mean storm water, groundwater, roof, yard, or site drainage. Also wastewater.
Sewer Main – A public sewer in a dedicated right-of-way. Also main line sewer.
Solid Waste – Non-liquid borne wastes normally considered to be suitable for disposal with refuse at sanitary landfill refuse disposal sites.
Standard Drawings - Those drawings included in Chapter 6 of this document or the latest edition of the APWA Standard Plans for Public Works Construction.
Tapping – The forming of a tee or wye branch connection to a sewer main by installing a tee or wye saddle after the sewer is in place. Also Connecting a Lateral.
Trunk Sewer – A sewer under the jurisdiction of the County Sanitation Districts of Los Angeles County.
Uncontaminated Water – Water not contaminated or polluted with sewage, and which is suitable, or could readily be made suitable, for discharge to the City’s storm water drainage system.
Waste Disposal Facility – A dump, solid waste disposal site, transfer station, sanitary landfill, land reclamation project, incinerator, or other similar site or facility which is used, or intended to be used, for the acceptance for transfer, salvage, or disposal of rubbish, garbage, or industrial waste, whether liquid or solid.
Work – All the work specified in the standard requirements, plans, specifications and standard drawings necessary to complete the construction of the sanitary sewer or associated facilities.
City of Downey Sanitary Sewer Design Guidelines, Policies, and Procedures
May 2023 2-1
Chapter 2 Permits, Fees, and Inspection Procedure
It is necessary to obtain all necessary permits before a project requiring the use or alteration of any sewer main or appurtenance in the City commences. Permits must be obtained at the Public Works Department Engineering Division Counter and/or the Building and Safety Division Counter at City Hall. Printed application forms for the permits required by this chapter are available at City Hall or can be obtained via the City website. Permits issued are not transferable from one person to another person or from one location to another location. No permit shall be issued if there are moneys due and owed to the City from the applicant.
2.1 Permit Application
Any person requiring a permit to connect to a public sewer shall submit a written application on printed forms or electronically via the City website to the City, giving a description of the lot or parcel to be served by the connection and any other information the City requires. Additional information than that requested on the printed form may be required from the applicant if it will enable the City to determine that the proposed work or use complies with the provisions of this document. Pertinent City forms are listed below and are available in Appendix A:
· City of Downey Public Works Encroachment Permit
· City of Downey Building & Safety Permit Application
· LACSD Sewer Connection Application
· LACSD District No. 2 Sewer Connection Fees
· LACSD District No. 18 Sewer Connection Fees
· LACSD Industrial Wastewater Discharge Permit Application · LACSD Industrial Wastewater Discharge Permit Application – Form A · LACSD Industrial Wastewater Discharge Permit Application – Form B · LACSD Industrial Wastewater Discharge Permit Application – Form C · LACSD Industrial Wastewater Discharge Permit Application – Form D
2.1.1 Tapping a Sewer Main
When it is necessary to connect a lateral to a public sewer at a location where no connection has previously been made, an application for a public sewer tap shall be submitted. A fee for tapping the public sewer shall be paid by the applicant before the permit is issued. All tapping of public sewers shall be performed by a licensed contractor approved by the Director of Public Works or an authorized representative.
2.1.2 Connecting to County Sewer
Any person proposing to connect to a trunk sewer shall contact the LACSD Chief Engineer for permit and fee requirements.
2.2 Industrial Waste Permit
The provisions of this section shall pertain to the disposal of industrial waste to the public sewer only.
LACSD builds, operates, and maintains trunk sewers and wastewater treatment and disposal facilities.
The City builds, operates, and maintains a system of local rsanitary sewer collection facilities. The two agencies jointly issue permits for industrial wastewater disposal, with LACSD having ultimate authority with regard to the quality and quantity of the discharge.
City of Downey Sanitary Sewer Design Guidelines, Policies, and Procedures
May 2023 2-2
2.2.1 Industrial Waste Permit Application
Applicants for a permit for industrial wastewater discharge shall complete LACSD’s application form available at City Hall, LACSD website, or in Appendix A. The applicant shall forward the application form and appurtenant plans and data to LACSD for review and approval. LACSD may require additional information on the characteristics of the wastewater discharge beyond that required on the application form. Detailed instructions for obtaining a permit are contained in the LACSD booklet, “Instructions for Obtaining a Permit for Industrial Wastewater Discharge,” which can be obtained at the office of the City Director of Public Works.
Upon receipt of all required information, the application shall be processed and, upon approval, be signed by representatives of both the City and LACSD and one copy returned to the applicant. When properly signed, the application form together with any documents attached thereto shall constitute a valid permit for industrial wastewater discharge.
2.2.2 Change of Permit Restrictions
LACSD may change the restrictions or conditions of a permit for industrial wastewater discharge from time to time as circumstances may require. The industrial discharger shall be allowed a reasonable period of time to comply with any changes required.
2.2.3 Revocation of Industrial Waste Permit
The Board of Directors of LACSD may suspend or revoke a permit for industrial wastewater discharge upon a finding that the discharger has violated any provision of current wastewater ordinances. No revocation shall be ordered until a hearing on the question has been held by the LACSD Board of Directors. At this hearing, the discharger may appear personally or through counsel, cross-examine witnesses, and present evidence on his own behalf. Notice of the hearing shall be given to the discharger at least fifteen (15) days prior to the date of the hearing.
2.2.4 Prohibited Industrial Waste Discharges
No person shall discharge any wastes to any public sewer which may have an adverse or harmful effect on sewers, maintenance personnel, wastewater treatment plant personnel or equipment, treatment plant effluent quality, public or private property, or which may otherwise endanger the public, the local environment, or create a public nuisance. Also discharge of any wastes which may adversely affect water reclamation procedures is prohibited.
The Director of Public Works or an authorized representative shall promptly investigate every complaint charging violation of any of the provisions of this part, and shall take action to correct any violation discovered. The Director of Public Works or an authorized representative may serve a violation to the person owning or operating a place where it is found to be in violation of their industrial waste discharge permit.
LACSD provides guidelines on concentrations of waste allowed to be discharged to the sewer.
Limitations on the concentration of several factors are restricted under the permit conditions, including:
· Fats, Oils, and Grease (FOG)
· Flammable Materials
· Hospital Waste
· Low pH
· Metals
· Odorous Waste
· Precipitates
· Radioactive Waste
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· Solid Waste
· Sulfides
· Temperature
· Toxic Wastes
2.3 Fees
The payment of all fees shall be made in advance of any work starting. The Director of Public Works or an authorized representative shall determine the fee based on the current fee schedule ordinance and provide a written estimate of services to complete the requested work. The Director of Public Works or an authorized representative shall keep a permanent and accurate account of all fees and charges received for each project. The information collected shall include the names and addresses of the persons or companies on whose accounts the fees and charges were paid, the dates and amounts paid, and for what purpose the fees were paid.
Current fee amounts are not specified in this document, since fees are reviewed and updated on a regular basis. For the most recent ordinance specifying fees, please contact the Director of Public Works or an authorized representative.
2.3.1 Refund of Fees
In the event that any person paid a fee and subsequently requested and received permission to revise the work so as to appreciably reduce the engineer’s estimate, a refund of a portion of the original fee shall be made. The difference between the original amount of the fee and a new amount will be determined from the revised valuation or total footage of main line and lateral sewers, or both. The Director of Public Works or an authorized representative shall determine the right to a refund. In all cases, a minimum processing fee will be charged and a complete refund will not be made.
2.3.2 Connection Fees
When requesting a connection to a sewer line, various fees are charged to the applicant. The fees are outlined in this section and based on the schedule of charges established by resolution adopted by the City Council.
Permit Fee
The fees for a permit to make a sewer connection shall be calculated based on the frontage of the portion of the parcel for which the permit is issued. If only a portion of an abutting parcel will be benefited by a sewer connection, the Director of Public Works or an authorized representative may issue a permit for the portion described in the written application. Proof that only such portion will be benefited by the sewer connection must be submitted.
If the shape of the lot or parcel is other than the usual rectangular shape, or if such lot or parcel is unusual in area, and the strict adherence to the above-mentioned provision would require a property owner to pay an amount not commensurate with the benefit to be received, the provisions of this section as to the amount to be charged may be modified as determined by the Director of Public Works or an authorized representative.
Fixed Sewer Connection Fee
When parcels connect to a new or existing sewer for the first time, a fixed sewer connection fee must be paid. The fixed fee applies to all sewers constructed on or after October 1, 1958. Dated record drawings of the sewer main construction are available for review at City Hall. In the event a connection is sought to be made to a sewer constructed prior to said date, the connection fees noted on the official sewer maps on
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file at the Public Works Department Engineering Division Counter and/or the Building and Safety Division Counter at City Hall shall be paid.
City Sanitary Service Charge
The City collects an additive to the bimonthly water bill to cover the cost of operating and maintaining the City’s sanitary sewer collection system. This fee is charged on the bimonthly water bill. Properties which are not presently served by the City’s water system shall also be billed for the sanitary service on a bimonthly basis.
2.3.3 Industrial Permit Fee
Applicants for an industrial waste discharge permit shall pay to the City, prior to issuance of such permit, all required fees. The fees are based on the schedule of charges established by resolution adopted by the City Council.
Surcharge Fee
A surcharge fee is payable annually or quarterly to the LACSD in an amount as specified in LACSD’s wastewater ordinance. The first payment will be due no later than the end of the first full quarter of sewer use.
Clean-up and Restoration
Any wastewater discharger, person, or business that discharges prohibited wastewater which causes damage to public facilities, detrimental effects on treatment processes, or any other damage shall be liable to the City and LACSD for all damages and for cleanup and restoration of such facilities.
2.3.4 Plan Checking Fee
The plan checking fee will be based on the latest cost included in the City’s annual fees which are adopted every fiscal year.
Plans will be approved only if conformance to this document is demonstrated to the Director of Public Works or an authorized representative. All required fees and charges shall be paid before approval of plans or issuance of a permit.
2.3.5 Sewer Easement Processing Fee
If construction of a sewer main in an undedicated street, alley, or other parcel is required, plans must first be reviewed and approved by the Director of Public Works or an authorized representative. The sewer easement right of way must be dedicated to the City, accepted by the City Council, and recorded by the LA County Recorder.
For each sewer easement processed, a fee for each parcel shall be paid to the City. In the event it is necessary to rewrite the description because of a realignment or revision, an additional fee for each new parcel description necessary shall be paid to the City.
2.3.6 Encroachment Permit Processing Fee
For each encroachment permit processed, a fee for each parcel shall be paid to the City.
2.3.7 Inspection Fee
An inspection fee shall be paid to the City by the applicant to cover the cost of field inspection of the proposed construction, automobile mileage, and all overhead and indirect costs. An initial estimate of inspection costs will be made based on the amount of work estimated. If additional inspection requests are made, additional fees may be charged.
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2.3.8 Lateral Connection Fee
The applicant shall pay to the City a fee for tapping into the public sewer. This fee covers the proportionate cost of operating and maintaining the sewer system.
2.4 Inspection
All work done in the City shall be subject to inspection by and shall meet the approval of the Director of Public Works or an authorized representative. The approval by the Director of Public Works or an authorized representative shall not relieve the permittee or any other person from complying with all of the applicable provisions of this document. The permittee shall furnish all labor, equipment, tools, and materials necessary for all tests, and the permittee or his representative shall be present at the job site at the time the inspection is made.
2.4.1 Maintenance Inspections
The Director of Public Works or an authorized representative may inspect as often as necessary every sewer main, lift station, wastewater treatment plant, industrial waste pretreatment plant, lateral connection, grease interceptor, waste disposal facility, or other appurtenances to ascertain whether the facilities are being maintained and operated in accordance with the provisions of this document. All persons shall permit and provide the Director of Public Works or an authorized representative with access to all such facilities at reasonable times. No person shall, during reasonable hours, refuse the entrance of the Director of Public Works or an authorized representative into any place in the performance of this duty.
2.4.2 Inspection of New Construction
Immediately after the work is ready for inspection, and at least twenty-four hours before inspection is to be made, the permittee shall request inspection by the Director of Public Works or an authorized representative at (562) 904-7110/7113.
At the time of inspection all work should be uncovered and convenient in order to make a thorough examination. Air and/or water used for testing shall be furnished, if requested. If any pipes are enclosed or covered in any way so as to obstruct a thorough inspection of the sewer construction or installation, the Director of Public Works or an authorized representative will notify the permittee to remove said obstructions. The Director of Public Works or an authorized representative will re-inspect the work once the obstructions are removed.
Defective Work to be Corrected after Inspection
Within ten (10) days after the Director of Public Works or an authorized representative notifies the permittee that any work is defective and fails to pass inspection, either in its construction or its material, the permittee shall reconstruct or remove such work and make it conform to the requirements of this document.
Exceptions to this requirement may be made only when the work is substantially complete and has been inspected, and if the Director of Public Works or an authorized representative determines that the best interests of the public will be served by permitting such use prior to completion of the work.
2.5 Project Completion
2.5.1 Certificate of Final Inspection
When it appears that all work done under the permit is completed to the satisfaction of the Director of Public Works or an authorized representative, a certificate of final inspection will be issued upon request.
All fees must be paid and all work must be done according to City standards and all applicable provisions
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of this document. The certificate shall recite that all work, as described by the permit, has been constructed according to this document and that the work is approved.
2.5.2 Record Drawings
At the completion of construction, record drawings signed by the engineer of record shall be submitted to the City. The submitted drawings should be corrected to conform to the work as constructed. The City will review the plans for completeness and will require them to be resubmitted, if necessary. Upon approval, one (1) final mylar copy and a CD or flash drive with the AutoCAD (latest version) files and a pdf copy of each sheet must be submitted to the City.
2.5.3 Sewer Dedication Requirements
An offer of dedication of sewers to the city shall be included in the agreement to construct sewers for a new subdivision which accompanies the faithful performance bond guaranteeing the construction required as a condition for the recordation of the tract map.
Before plans for the construction of any other public main line sewer are approved by the Director of Public Works or an authorized representative, the person causing such plans to be prepared shall present an “Offer of Dedication,” signed and acknowledges, on forms provided by the Director of Public Works or an authorized representative.
When the construction of the sewer has been completed and the “Offer of Dedication” presented to the Director of Public Works or an authorized representative and construction accepted by the City Council, the sewer becomes a public sewer. No sewer shall be accepted for dedication by the City unless it has been constructed in conformity with the requirements of this document and any applicable ordinances.
2.5.4 Warranty Period
Once construction of the sewer has been completed and accepted by City Council, all work shall be guaranteed for a period of one (1) year. This includes the replacement of defective materials and remedy to any issues associated with workmanship. The warranty provides a guarantee against settlement of backfill, damage to pavement, and damage to sewer facilities for a period of one (1) year from the date of City Council acceptance.
A warranty bond will be provided to the City at no expense to the City. The bond should be for 25% of the construction cost and will be held until the end of the warranty period.
2.6 Sewer Easement Requirements
A person proposing to construct a sewer in an easement shall present to the Director of Public Works or an authorized representative a request for processing a sewer easement with sufficient information to enable the preparation of a written description along with required fees. The location and dimensions of sanitary sewer easements shall be sufficient to provide present and future sewer service to abutting areas and adequate access for maintenance as determined by the Director of Public Works or an authorized representative. Until the required easements have been properly executed and recorded, no plans shall be approved by the Director of Public Works or an authorized representative for sewer facilities to be constructed by any person across the property of others.
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Chapter 3 Standards of Design for Sewers
Before granting a permit for the construction of any sewer and/or appurtenances the Director of Public Works or an authorized representative shall check and approve the plans. The plans shall comply with all standards of design required by this document and any City ordinances. In an effort to reduce costs and avoid the need to reconstruct sewer facilities not properly constructed, the City requires that new sewer facilities be designed and constructed in the manner that is best suited for existing and future service requirements.
If compliance with any requirement of this chapter is impossible or impractical because of peculiar conditions and if an alternate construction or procedure is feasible, the Director of Public Works or an authorized representative may grant an exception to permit an alternate construction or procedure.
3.1 Estimating Flow Rate
Sewer flows shall be calculated using appropriate industry standard techniques. The flow estimates must account for all proposed upstream development. Any person proposing to have sewage discharged from any property to a public sewer at a rate greater than the capacity for which the sewer was designed shall be denied a permit to connect any facilities to the sewer unless such person replaces the existing sewer and associated facilities with new collection facilities capable of handling the flows and obtains approval from LACSD that they have adequate capacity to handle the flows.
3.1.1 Average Flow Rate
A flow factor of 215 gpd/EDU shall be used to calculate average sewage flows. Table 3-1 presents EDU factors that should be used to determine the number of EDUs for a new property.
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Table 3-1: EDU Flow Factors
Use Category EDU
Factor
Single Family Residence 1.0
Multiple Dwelling Unit (apartments, duplexes, condominiums, townhouse), per living unit 1.0 Mobile Home/Trailer Park, per mobile home or trailer space 1.0 Motel or Hotel, per unit 0.50
Medical Care or Elder Care (Hospital, skilled nursing home, convalescent home, retirement home, assisted living homes, and similar facilities)
Individual units or beds, without kitchen
Individual unit with kitchen
0.4 1.0
Churches, Theatres, and Auditoriums, per unit of 115 persons or fraction thereof 1.0 Schools
Elementary, per 60 pupils or fraction thereof
Junior High, per 50 pupils or fraction thereof
High School, per 30 pupils or fraction thereof
1.0 1.0
1.0 Self-Service Laundromats, per washer 0.75
Food Establishment, Restaurant, Tavern
Each unit of 7 seats or fraction thereof
Restaurant with No Seating
Tavern not serving food, per each unit of 16 seats
1.0 2.6
1.0 Ballroom, Banquet Facility, and Convention Facility, per block of 40 seats 1.0 Automobile Service Station 3.0
Car Washes
Evaluated based on peak net discharge rate to sewer
Based on
Individual
Review
Commercial or Industrial Users
Up to 1,000 SF
Plus for each additional 1,000 SF or portion thereof up to 5,000 SF Plus for each additional 1,000 SF or portion thereof over 5,000 SF
1.0 0.4
0.6 Other Users Based on
Individual
Review
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3.1.2 Peak Flow Rate
Peak flow rate is the rate at which sewage is discharged to a public sewer during the highest thirty (30) minute flow period of any twenty-four (24) hour period. Sewer pipelines must be designed and sized using peak flow conditions. The peak flow rate shall be determined by multiplying average flows by a peaking factor. Peaking factors shall be determined based on population served. Acceptable peaking factors are presented in Table 3-2.
Table 3-2: Peaking Factors
Population Served Peaking Factor
Less than 5,000 Calculatea
5,000 3.10
10,000 2.88
15,000 2.75
20,000 2.66
30,000 2.53
40,000 2.44
60,000 2.31
80,000 2.22
100,000 2.14
150,000 2.01
Footnotes:
a. Use the following formula for populations less than 5,000, where P = Population in thousands:
Q maximum /Q average = (18 + (P^0.5)) / (4 + (P^0.5))
3.2 Sizing Sewer Mains
3.2.1 Minimum Diameter
Sewer main pipe shall have an inside diameter of not less than eight (8) inches. Laterals shall be a minimum of four (4) inches in diameter.
3.2.2 Slope
The slope of the sewers shall be shown on the plans in feet of fall per one hundred feet of horizontal distance, expressed as a percentage. Minimum slopes for a range of pipeline sizes and conditions are provided in Table 3-3. Generally, sewer pipelines shall be designed to produce a minimum allowable velocity of 2 feet per second (fps) and a maximum velocity of 10 fps. The Director of Public Works or an authorized representative may approve plans showing a gradient which will create a lower velocity than 2 fps if it is determined that the minimum velocity is unobtainable.
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Table 3-3: Minimum Pipeline Slopes
Pipeline Size (inches) Minimum Pipeline Slope (%)
4 (laterals only) 2.00
6 (laterals only) 2.00
8 (connecting less than 10 homes) 2.00
8 (serving 11 – 40 homes) 1.00
8 (serving 41+ homes) 0.40
10 0.30
12 0.25
15 0.15
18 0.10
21 0.08
Steep Slope Protection
Sewer mains with a 20 percent slope or greater shall be anchored securely with concrete, or equal, anchors spaced as follows:
· Not over 36 feet, center to center, on grades 20 % – 35% · Not over 24 feet, center to center, on grades 35% – 50% · Not over 16 feet, center to center, on grades 50% and over
3.2.3 Pipeline Size Criteria
In general, gravity sewer pipelines shall be sized to achieve the minimum required velocity using open channel flow formulas under peak conditions. Manning’s formula for open channel flow shall be used for the hydraulic calculations. A Manning’s coefficient of roughness of 0.013 shall be used for all pipeline conditions unless otherwise approved by the Director of Public Works or an authorized representative.
The desirable, ultimate flow depth under peak conditions (expressed as depth of water over diameter of pipe) shall not exceed the guidelines set in Table 3-4. The sizing calculation shall be submitted with the plans when they are submitted for review.
Table 3-4: Depth of Flow
Diameter Pipe (inches) Capacity: Depth over Diameter (d/D) 8 50
10 60
12 70
15 75
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3.3 Pipeline Separation
The horizontal separation between sewer and potable water pipelines shall be minimum 10 feet pipe edge to pipe edge as required by the State of California Division of Drinking Water guidelines. Encasement and/or casing/sleeving may be required when 10 feet of separation cannot be achieved.
The minimum horizontal separation between sewer and all other utilities is 5 feet, unless otherwise approved by the Director of Public Works or an authorized representative.
A minimum vertical separation of one foot (1’) pipe edge to pipe edge shall be provided and the sewer shall cross under water and recycled water pipelines, unless the Division of Drinking Water provides written approval.
3.4 Minimum Depth of Sewer
The minimum depth for sewer mains in residential areas shall be 7.5 feet below the roadway surface. The standard depth for laterals shall be six feet (6’) in residential areas and eight feet in commercial, industrial, apartment house areas, all depths measured from finished surface to pipe invert at the property line.
3.5 Sewer Alignment
Whenever possible, sewers should be located on the centerlines of streets or easements to provide easier access to manholes. Pipelines should not be located under median strips or parking lanes. Sewers shall be placed on straight lines between structures whenever possible. Sewer mains shall be located not more than five feet (5’) from the centerlines of streets or alleys, except on major highways where separate sewers shall be located in the roadway six feet (6’) from either curb line or as necessary to meet separation requirements.
3.5.1 Change in Direction at Manholes
The maximum change in direction allowed along any sewer main is 90-degrees at which point a manhole must be installed.
3.5.2 Easements
The minimum easement width required is 20 feet, except when authorized by the Director of Public Works or an authorized representative. Any encroachment into an easement requires an encroachment permit. The minimum distance from the centerline of the sewer to the edge of the easement shall be 10 feet.
3.5.3 Utility Crossings
Unless otherwise approved, sewers shall cross other utilities at a perpendicular angle.
3.5.4 Horizontal Curves
Where design considerations permit, sewer mains shall have a straight alignment. Horizontal and vertical curves are not permitted in the same length of pipe. Where necessary, sewer mains may be designed along curves with minimum radii of one hundred feet (100’) or as otherwise approved by the Director of Public Works or an authorized representative.
3.6 Manholes
Manhole structures shall be placed in the sewer main at all changes of horizontal alignment or gradient and at all intersections. The maximum distance between manholes shall be not more than three hundred fifty feet (350’); greater spacing may be allowed in large diameter sewer mains.
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Each sewer main must end at a manhole. End manholes shall be placed at whichever of the following locations is farthest upgrade:
· Not less than ten feet (10’) upgrade from the downgrade lot line of the last lot being served; · Not more than forty feet (40’) downgrade from the upgrade lot line of the last lot being served, if there may be a future extension of the sewer main;
· At a location where the lateral sewer can be constructed in a straight alignment at right angles to the sewer main.
3.6.1 Drop Manholes
A drop manhole shall be provided for a sewer entering a manhole at an elevation of 24 inches or more above the manhole invert. Where the difference in elevation between the incoming sewer and the manhole invert is less than 24 inches, the invert shall be filleted to prevent solids deposition.
3.6.2 Diameter
Manholes shall have a minimum diameter of 48 inches; larger diameters are preferable for large diameter sewers. A minimum access of 24 inches shall be provided.
3.6.3 Flow Channel
The flow channel straight through a manhole should be made to conform as closely as possible in shape and slope to the connecting sewers. The channel walls should be formed or shaped to the full height of the crown of the outlet sewer in such a manner to not obstruct maintenance, inspection, or flow in the sewers.
3.6.4 Bench
A bench shall be provided on each side of any manhole channel when the pipe diameter(s) are less than the manhole diameter. The bench should be sloped no less that ½ inch per foot {4 percent (%)}. Bench construction shall use stone, course aggregate, washed gravel, or other materials which will not readily erode, cause siltation, damage pipe during placement, or corrode the pipe.
3.7 Laterals
Laterals shall be designed at a minimum depth that is sufficient enough to provide a connection to the lowest and/or farthest point of the lot with a cover of one foot (1’) at that point and a grade of not less than one percent (1%). Laterals should be a minimum of four inch (4”) diameter for residential and a minimum of six inch (6”) diameter for commercial. The alignment and grade of a lateral shall be straight from the public sewer to the street property line and shall be perpendicular to the centerline of the street.
3.8 Substructures
All substructures which will be encountered in the construction, or which will be installed as part of the improvement, shall be shown and designated on the plans. Large substructures which require special treatment in the design of the sewer shall also be shown in the profile. The permittee shall submit to the Director of Public Works or an authorized representative a statement from each utility company having substructures in the affected area, certifying that the location and size of such structures, as shown on the plans, are the same as shown on their records.
3.9 Soil Conditions
Soil conditions, particularly in areas known to have high groundwater tables, rock, or filled ground, shall be investigated and the results shown on the profile, if required by the Director of Public Works or an authorized representative.
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3.10 Bench Marks
A system of bench marks needed to construct the work accurately must be shown on the plan and profile drawings. Bench marks shall be labeled as established by the North American Datum of 1983 (NAD 83) California Zone 5 State Plane Coordinate System for Horizontal Control and North American Vertical Datum of 1988 for Vertical Control. The elevation of the sewer at the point where the new sewer main is to discharge into existing shall be field verified and labeled as such in the above-shown datum.
3.11 Sewer Service for Large Parcels
When a lot or parcel of land is of sufficient size to be divided into smaller legal-sized parcels, each of such parcels shall be considered as a separate parcel of land and separate laterals shall be provided to connect to the sewer main from each such parcel. Before actual connections are made, the development on the parcel shall have complied with the provisions of this chapter. If the sewer main does not extend to a point from which such parcels of land can be served, the property owner shall construct a sewer main and/or extension so that such parcels may adequately be served.
Multi-unit Properties
New condominium developments shall be served with sewer mains and laterals such that each building will have a separate and independent connection to a sewer main.
3.12 Construction Materials
The City has adopted the “Standard Specifications for Public Works Construction” (Greenbook), latest edition plus any supplements, as the specifications to be used to establish standards of work, materials, and construction procedures for improvements to the sewerage system within its boundaries. If in conflict, the requirement in this document takes precedence over the Greenbook.
All materials used in any work done shall be new, high grade, and free from defects. The Director of Public Works or an authorized representative may order tests of any materials at the expense of the permittee, to determine whether such materials meet said specifications.
3.12.1 Sewer Pipes
Sewer mains and laterals within the City right-of-way shall be constructed with extra strength vitrified clay pipe. Laterals not within the City right-of-way may be constructed with vitrified clay pipe or green polyvinyl chloride (PVC) pipe. With the prior approval of the Director of Public Works or an authorized representative, sewer pipe other than vitrified clay or green PVC may be considered for construction, provided that it is equivalent to vitrified clay or green PVC in strength, effectiveness, durability and safety in accordance with the use intended. Before approving any pipe, the Director of Public Works or an authorized representative may require satisfactory proof that such pipe is suitable for use, including actual tests performed by an independent and approved testing laboratory at no expense to the City. The specific type of pipe joint shall be designated on the plans.
3.13 Construction Methods
All construction, installation and alteration of sewer mains, laterals and structures shall be performed in accordance with the provisions of this chapter and with those of the “Standard Specifications for Public Works Construction” (Greenbook), latest edition. The Greenbook is on file at the Public Works Department Engineering Division Counter and/or the Building and Safety Division Counter at City Hall and has been adopted as the standard specifications.
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3.13.1 Excavations
All excavations shall have sufficient width to allow proper workmanship and permit adequate inspection.
The trench walls shall be supported in the manner set forth in the codes and regulations of the California Department of Industrial Relations, Division of Occupational Safety & Health. Access to trenches shall be in accordance with the standard specifications.
3.13.2 Wet or Soft Ground
Before laying any sewer pipe in an excavation of soft, wet, or spongy soil, sufficient gravel, crushed rock, or other suitable based material to stabilize the subgrade shall be placed in the bottom of the trench.
3.13.3 Avoidance of Trees
Sewer pipe shall be laid a minimum distance (measured horizontally, along the expected finished surface elevation) of ten feet (10’) from any tree, bush, or hedge. When a sewer pipe is located closer than ten feet (10’), the Director of Public Works or an authorized representative may require that the pipe be encased in Portland cement concrete, suitable cement slurry, and/or casing/sleeve.
3.13.4 Sewer under other Structures
When a sewer pipe is proposed to be located under railroad tracks, storm drains, trunk sewers, or other structures, the pipe may be required to be encased in Portland cement concrete, or it may be required to be laid inside a suitable steel casing with end caps and spacers. The space between the inside of the casing and the pipe may be required to be filled with sand.
3.13.5 Shallow Sewers
Whenever a sewer main is proposed to be located at a depth which is less than four feet (4’) between finish grade and the invert of the pipe, such pipe may be required to be encased in Portland cement concrete, suitable cement slurry, or casing pipe. The Director of Public Works or an authorized representative shall make the final determination about the length of encasement, and details should be included on construction drawings.
3.13.6 Placing Vitrified Clay Pipe
Vitrified clay piping shall not be placed closer than two feet (2’) to the exterior wall of any building or closer than twelve inches (12”) to the surface of the ground at any point in its course.
3.13.7 Laying Pipe
All pipe shall be laid upgrade on an unyielding foundation, true to line and grade, and with a uniform bearing under the full length of the barrel of the pipe. Bell and spigot pipe shall be laid with sockets upgrade. Suitable excavations shall be made to receive the bells or collars of the pipe. All adjustments to bring the pipe to line and grade shall be made by scraping away or thoroughly tamping suitable fill material under the body of the pipe and not by wedging or blocking.
3.13.8 Tapping Public Sewer
Whenever it is necessary to perform a tapping of a sewer main in order to connect a lateral, the applicant shall provide the excavation exposing the public sewer sufficiently for the contractor to install the “Y” or “T” saddle.
3.13.9 Work Shall be Watertight
Every sewer constructed under the provisions of this chapter shall be watertight and shall be subject to the testing procedure described in Greenbook.
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The installation of joints and the materials used shall be as provided in the specifications. Sewer joints shall be designed to minimize infiltration and to prevent the entrance of roots throughout the life of the system.
3.13.10 Disposal of Excavated Materials
All material excavated from a sewer trench, and which is suitable as backfill, shall be laid neatly alongside the excavations and kept trimmed up so as to cause as little inconvenience as possible to public travel, or the material may be required to be hauled away from the worksite and stored temporarily at a suitable location. All material excavated in streets and roadways that are not required or suitable for backfilling shall be immediately removed and disposed of by the permittee.
3.13.11 Traffic Control
The permittee shall at all times during construction comply with the requirements for traffic control as prescribed in the permit application and as directed by the Director of Public Works or an authorized representative. The permittee shall conduct his operations so as to exhibit the utmost regard for the safety and welfare of his personnel and for the traveling public as well.
3.14 Lift Stations
Sanitary sewer lift stations should be avoided whenever possible. Prior to the start of design of any lift station or submittal of any drawings, meetings with the Director of Public Works or an authorized representative and operations staff shall be held to discuss the design criteria. During construction, inspections or operational checks for compliance with all requirements will be coordinated with City staff until completion.
Depending on the location the site may be required to be landscaped in an acceptable manner as determined by the Director of Public Works or an authorized representative. The landscaping shall be similar to the adjacent area landscaping in a manner satisfactory to the City. Lift stations may be required to be secured by a fence, wall, or other means necessary to adequately prevent unwanted entry depending on the location.
Vehicular access roads to lift stations outside of street areas shall be paved and a minimum of 20 feet wide. There shall be a parking area for two, one-ton trucks with a turnaround.
3.14.1 Pumps
Submersible pump(s) (1 duty, 1 standby) held in a single wet well is the preferred pump station layout.
Alternatives to this arrangement will be reviewed on a case-by-case basis and shall be designed based on the standards in this section.
Submersible pumps and motors shall be designed for raw wastewater use, including totally submerged operation during a portion of each pumping cycle. An effective method to detect shaft seal failure or potential seal failure shall be provided. The minimum submersible, non-clog sewage pump size shall be 4 inches with the capability of passing a 3 inch sphere. Where smaller pumps are required, grinder type pumps shall be used.
Pump Curves
The specified operating point shall be near the maximum efficiency point on the pump curve and within the manufacturer-recommended limits for radial thrust and vibration. Select a pump curve where the operating point will be near the center of the pump’s recommended operating range. The most efficient pumps are found operating at the design Total Dynamic Head (TDH). Avoid pumps with flat pump curves, where a small change in TDH will result in a large change in pump flow.
Pump equipment shall be dynamically balanced to prevent vibration. No surge cavitations or vibrations shall be allowed within the limits of the stable operating range indicated on the pump curve.
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A factory certified pump test curve for the actual pumps to be installed is required. Pump curve data shall be submitted for review and approval. This shall include the following: system curve, design operating point, required net positive suction head (NPSH), hydraulic efficiency, horsepower requirements, Revolutions per minute (RPM), and other operating conditions required for each pump. Pump curves shall be shown on the submitted set of drawings.
Pump Cycle Times
The minimum pump cycle time shall be in accordance with the pump and motor manufacturer’s requirements. Note that larger motors require longer times between starts.
Pump Removal
Submersible pumps shall be readily removable and replaceable without personnel entering or dewatering the wet well, or disconnecting any piping to the wet well.
3.14.2 Piping and Appurtenances
Pump isolation valves (suction and discharge) shall be round port plug valves with suitable operators (such as hand wheels or nuts) per manufacturer’s recommendation.
Piping shall be green DR14 PVC or Class 52 Protecto 401 lined in accordance with AWWA standards.
Pipe joints must be restrained. The following types of joints are acceptable: flanged, sleeve-type coupling restrained by tie rods, mechanical joint with set bolt retainer gland.
3.14.3 Controls
All pumps shall be equipped with approved instrumentation and telemetry, which shall be compatible with the City’s Supervisory Control and Data Acquisition (SCADA) System.
3.14.4 Alarms
Dry well should have a “flooded” alarm. Wet well shall have a high level and low level alarm independent from the pump controls. Additionally, alarms should be sent during the pump failure, leak detection, and unauthorized entry. Instrumentation and alarms shall be connected to the City’s SCADA system.
3.14.5 Dry Well
All interior concrete surfaces shall be coated with a City-approved sealer. All exterior buried walls and roofs shall be waterproofed. Provide sump and sump pumps to convey nuisance water out of the dry well.
All exposed welds shall be coated with non-corrosive coatings. All equipment shall have adequate clearance to perform maintenance and repair work. Guards shall be required around all moving parts of equipment as required by safety codes. Safety warning signs shall be installed on all hazardous equipment. All concrete floors shall be treated with an approved coating. All outside doors and frames shall be corrosion and vandal resistant.
3.14.6 Wet Well
Wet well working volume shall be calculated and submitted for approval, including submittal of maximum number of motor starts allowable per hour per motor manufacturer. Every lift station shall provide emergency storage. The minimum storage volume shall be equal to two (2) hours of peak flow in order to allow for adequate response time by City Utilities Division Staff. The volume of emergency storage may be adjusted based on site specific conditions and proximity to sensitive receiving areas. The wet well should be as small as possible to prevent septic action from taking place during periods of very low flow. However, the wet well must be large enough to provide at least 5 minutes pump running time at low flow to prevent overheating of the electrical motor and controls.
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Wet well walls and ceiling shall be PVC-lined with T-lock, as manufactured by Ameron Pipe, or equal.
The exterior surface shall be adequately water-proofed to prevent intrusion of groundwater.
Wet well floor shall be sloped toward the suction piping at 1/8 inch per foot. Inlet into the wet well shall be above the high water operating level in order to allow for the free flow of gases into the wet well.
3.14.7 Operations and Maintenance
The Design Engineer shall provide an operations and maintenance manual for review and approval.
3.15 Force Mains
Friction losses through force mains shall be based on the Hazen-Williams formula or other acceptable methods. When the Hazen-Williams Formula is used, the value for “C” shall be 100. For other smooth pipe materials such as PVC, polyethylene, lined ductile iron, a higher “C” value not to exceed 120 may be allowed.
3.15.1 Velocity and Diameter
At design pumping rates, a cleansing head velocity of at least two (2) feet per second should be maintained. The minimum force main diameter should not be less than four inches (4”).
3.15.2 Appurtenances
Air vacuum valves shall be placed at high points in the force main to prevent air locking. The force main configuration and head conditions should be evaluated as to the need for and placement of vacuum relief valves.
Cleanouts at low points shall be considered for any force main to facilitate maintenance.
3.15.3 Termination
The force main shall enter the receiving manhole with a smooth flow transition to the gravity sewer system at a point not more than 1 foot above the flow line. Corrosion protection for the receiving manhole shall be provided.
3.15.4 Pipe and Design Pressure
Pipe and joints shall be equal to water main strength materials suitable for design conditions. The force main, reaction blocking, and station piping shall be designed to withstand water hammer pressures associated with cyclic reversal of stresses that are expected with the cycling of sanitary sewer lift stations.
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Chapter 4 Pipe Rehabilitation
The purpose of this section is to provide guidelines for the methods and selection criteria for pipeline rehabilitation. It is the responsibility of the design engineer to become familiar with rehabilitation techniques and the applicability for a particular situation. Not all techniques are appropriate for a given pipe material, pipe diameter, pressure condition, or to provide support to an existing pipe with degraded structural integrity. The proposed rehabilitation method must be approved by the Director of Public Works or an authorized representative prior to construction.
4.1 Definitions
The following terms as found in this section shall have the following meaning.
Carbon Fiber Relining (CFR) – The use of carbon fiber cloth and epoxy resin placed on the interior surface of a pipe.
Cement Mortar Lining (CML) – A lining process in which a cement/morter is installed inside the pipe lining to the interior wall of the pipe to provide a monolithic layer that inhibits further deterioration of the pipe.
Close-Fit Pipe (CFP) – A procedure of installing a polyethylene (PE) pipe with a temporarily condensed or modified cross-section into an existing shape. Once in place, the pipe is expanded to its normal shape forming a tight fit with the existing pipe.
Cured In Place Pipe (CIPP) – A lining process in which a slim, pliable tube of fiberglass fabric or polymer is infused with resin. The tube is then expanded by means of fluid or air pressure into position on the inner wall of a defective pipeline before thermally curing the resin to harden the material.
Dig and Replace – A method of replacement where the original pipe is exhumed and pipe segments are replaced with new pieces.
Localized Repair (or Spot Repair) – Localized repair is a name given to the use of a number of varying technologies to refurbish an isolated segment of pipe rather than the replacement of an entire reach. This may serve to repair a defective point in a pipe due to a manufacturer’s defect, poor installation, root intrusion, or deterioration. The localized repair techniques consist of robotic repair, grouting, internal seal, and cured in place pipe.
Modified Slip Lining (MSL) – Method in which a liner is segmented, inserted, and pieced together inside of the faulty pipe. One common method is spiral wound pipe where a continuous strip of Polyvinyl Chloride is fed into a winding machine that wraps the interior of a defective pipe. A second method is Panel Lining in which panels of a smaller diameter are inserted into the defective pipe and chemically bonded or welded in place.
Pipe Bursting (PB) – Pipe bursting is a process by which the bursting unit splits and/or fractures the existing pipe into the surrounding soil while simultaneously installing a new pipe of the same or larger size.
Pipe Removal (PR) – Pipe removal is a similar technology to pipe bursting, but relies on horizontal directional drilling or microtunneling to excavate and remove pipe fragments rather than displacing them into the surrounding soil.
Slip Lining (SL) – Insertion of a new pipe by pulling or pushing it into the existing pipe and grouting the annular space.
Thermoformed Pipe (ThP) – The use of a new polyvinyl chloride (PVC) or polyethylene (PE) pipe that is folded or deformed until it is inserted in the existing pipe and then expanded with a hot fluid (typically steam) and pressure to fit tightly inside the existing pipe.
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Underground Coatings and Linings (UCL) – The use of cement (cement mortar lining), epoxy, shotcrete, or gunite to provide a monolithic layer that inhibits further deterioration of the pipe.
4.2 Inspection
The inspection and identification of the location of necessary repairs are critical to the success of a rehabilitation program. Inspection shall be done either by closed circuit television (CCTV) or visual inspection in large diameter pipe. Other inspection methods, such as smoke testing, may identify that a problem exists without identifying the exact location or nature of the problem. Some of the types of sewer main defects are: tie-in connection damage; corrosion; cracks or fractures; debris or obstructions; deformation; holes; inflow, infiltration, or exfiltration; root intrusion; offset joints; separated joints; or sags.
4.3 Planning
Once the defect is located and identified, planning should be performed to determine the proper course of action. The following pieces of information should be gathered before a decision is made:
· Pipeline inspection results (location and defect type/severity) · Wastewater type and characteristics (pH, potential for corrosive gas production, etc.) · Pipeline environmental conditions (soil pH, site constraints, accessibility, etc.) · Pipe properties (diameter, material, types of joints, etc.) · Pipeline capacity
· Location and number of service connections on pipe reach · Structural integrity of damaged pipe
· Joint locations
· Prioritization of the repair and likelihood of a pending failure · Modeling of potential solutions that reduce pipe diameter or change friction values.
The selection of the rehabilitation technique is based on a number of factors and ultimately the pipe age and the cost of repair versus the cost associated with replacement of the entire facility. In many cases when a pipe has reached the end of its lifecycle and additional capacity is needed, repairs may not be as efficient as replacement or upsizing to a larger diameter facility. Table 4-1 may help to select the pertinent rehabilitation technique for the specified defect.
4.4 Preparation
4.4.1 Cleaning
Many of the pipeline rehabilitation processes require a clean inner pipe surface prior to the implementation of the method. The cleaning method may be mechanically powered equipment, high velocity hydraulic equipment (hydro-cleaning), and hydraulic propelled cleaning equipment. For severe defects, care should be taken to not cause further damage while cleaning. Damage to a sewer main in many cases is accompanied by obstructions such as tree roots, collapsed pipe and/or subgrade material, or deformed pipe. It may be necessary to use a root cutting apparatus and/or a mechanical tool to reshape the pipe.
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Table 4-1: Applicability of Rehabilitation Method for Specified Defects Rehabilitation
Method
Joint
Separation
Joint
Problems Corrosion Cracks/
Holes
Inflow,
Infiltration,
and
Exfiltration
Structural
Problems
Cured in Place Pipe Yes Marginal Yes Yes Yes Yes
Slip Lining Yes Marginal Yes Yes Yes Yes
Close-Fit Pipe Yes Marginal Yes Yes Yes Yes
Pipe Bursting Yes Marginal Yes Yes Yes Yes
Pipe Removal Yes Marginal Yes Yes Yes Yes
Localized Repair-
Robotic Repair Yes Marginal No Marginal Yes Marginal
Localized Repair –
Grouting Yes Marginal No Marginal Yes No
Localized Repair –
Internal Seal Yes Marginal Yes Yes Yes Yes
Localized Repair –
Cured-In-Place Yes Marginal Yes Yes Yes Yes
Modified Sliplining –
Panel Lining Yes Marginal Yes Yes Yes Yes
Modified Sliplining –
Spiral Wound Yes Marginal Yes Yes Yes Yes
Underground Coatings
and Linings – Cement
Mortar Yes Marginal Yes Yes Marginal No
Underground Coatings
& Linings – Epoxy
Lining Yes Marginal Yes Yes Marginal No
Underground Coatings
& Linings – Shotcrete Yes Marginal Marginal Yes Marginal Yes Underground Coatings
& Linings – Gunite Yes Marginal Marginal Yes Marginal Yes Thermoformed Pipe Yes Marginal Yes Yes Yes Yes
Carbon Fiber Relining Yes Marginal Yes Yes Yes Yes
4.4.2 Temporary Service Connections
Prior to executing a pipe rehabilitation method, any existing customer that maybe impacted by an outage will need to be notified. When feasible, customers should remain in service or be provided with a temporary service. When infeasible, the project may need to be done in phases to alleviate the time any given reach of pipe is out of service. Appropriate communication to the effected occupants of a property is critical.
4.4.3 Bypass Requirements
For areas that do not have multiple or redundant service from several directions, a plan will need to be implemented for bypassing the reach of pipe being repaired. The bypass shall consist of all
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materials/equipment/labor (i.e. pumps, hosing, piping, portable generators, etc.) necessary to install and maintain the temporary bypass to the satisfaction of the City. The bypass requirements should be completed far enough in advance of the arrival of the labor force and the materials for rehabilitation to allow adequate time to resolve any unforeseen problems.
4.5 Execution
4.5.1 Inspection
An inspection by a party familiar with the selected rehabilitation process is imperative to the successful repair of a facility. Many repair processes are proprietary in nature, so the ability to find an experienced inspector may need to be considered during the planning stage.
4.5.2 Service Reconnection
Any services within the reach of the pipe being repaired will need to be reconnected. Some techniques require the excavation of each service and manual reconnection/replacement. Other processes may implement a robotic cutting arm to cut a hole in the new pipe or liner where the existing services were located. As with inspection, the number of services that need to be reconnected needs to be considered during the planning stage. If several excavations are needed on a particular pipe reach to reconnect service laterals, an open cut replacement of the existing facility may be more cost effective.
4.5.3 Post Repair CCTV
The new facility should be televised and/or visually inspected after the repair has been made. Some processes or linings may not have uniform coverage. Additional repairs may be necessary prior to the acceptance of the job. The specifications for the project should reflect the conditions that are needed for approval of the improvement.
4.6 Pipe Bursting
Pipe bursting is discussed in further detail in this section since it has been identified as a potential method by the City for pipe rehabilitations. The success of pipe bursting is highly dependent on soil conditions, existing pipe material, and condition. Burst length coupled with soil conditions, depth and new pipe diameter are critical factors in the planning of the pipe bursting process. The International Pipe Bursting Association (IPBA) classifies pipe bursting work into three classifications, as shown in Table 4-2. These classifications are meant to be used as a general guideline when considering replacement of an existing pipe by pipe bursting.
Table 4-2: Pipe Bursting Classifications
Depth of Pipe Existing Pipe
Diameter
New Pipe
Diameter Options Burst Length
Routine 12 feet and 18 feet 20 – 36 inches Up 3 or more sizes >450 feet
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Pipe Materials
The new pipe shall be sufficient in diameter and thickness to renew the required flow capacity and pressure. The pipe shall be of virgin materials and be homogenous throughout, and shall be free of visible cracks, holes, foreign material, blisters, or other deleterious faults. Most pipe bursting projects utilize fused lengths of HDPE pipe. The following pipe materials shall be considered on a case by case basis as acceptable replacement materials:
· High Density Polyethylene Pipe (HDPE) – conforming to ASTM F714, AWWA C906, ASTM D1248 or ASTM D3350.
· Steel Pipe – conforming to AWWA C200
· Ductile Iron Pipe (DIP) – conforming to AWWA C104, C110, C111, C116, and C151; and ASTM B-117, D-714, D-1308, E-96, G-14, and G-95; Protecto 401 lined; and shall be specifically designed for jacking by the pipe manufacturer. · Polyvinyl Chloride (PVC) Pipe – restrained joining type such as Certa-Lok or Yelomine and conforming to the requirements of ASTM D2241 and/or AWWA C900 or C905, with a DR11 rating.
· Vitrified Clay Jacking Pipe (VCP-J) – 316 stainless steel collars; conforming to ASTM C 1208.
Host Pipe Size and Depth
Small diameter host pipe in difficult soil conditions can present problems because larger, more powerful hammers will not fit inside the host pipe. Special nose tools should be considered to solve this problem.
The depth of the host pipe affects the bursting process in a number of ways, such as:
· Existence of groundwater may require more dewatering
· Soil expansion subsequent to the pipe burst may become more difficult due to the additional weight of the soil
· Depending on the type of soil, upsizing new pipe may require additional soil expansion · Entrance and exit pits will require additional shoring due to required safety procedures · The magnitude of an allowable bend in alignment may require reduction due to the additional soil load
A California Registered Geotechnical Engineer shall perform geotechnical investigations and produce a soils report to determine soil types.
Lateral Excavations
It is recommended that all laterals be located, exposed, and disconnected prior to bursting to reduce damage and the time required for service reinstatement.
Launching and Exit Pits
Pits are usually located outside of heavy traffic areas and intersections, and are generally near manholes to permit gradual entry of the burst equipment and new pipe into the host pipe. As a rule of thumb, the launch pit length should be 2.5 times the depth of the existing pipe. Steep entries may put excessive strain and friction on the new pipe. Exit pits must be sized to permit pipe bursting equipment removal and allow manhole connections to the new pipe. Launching and exit pit width, measured at 1 foot above the exterior top of pipe, shall be at least 15 inches greater but not more than 24 inches greater than the exterior width of the pipe.
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Contractor Qualifications
The Contractor will be required to have these minimum qualifications:
· Several applicable pipe bursting projects previously and successfully completed by the Contractor.
· The Contractor shall furnish a list of references (minimum of 3) where pipe bursting was used in similar ground conditions.
· The Contractor shall be trained and certified to operate the required pipe bursting equipment and systems. The Contractor shall provide certifications of training and proficiency in the use of the equipment.
· The Contractor must have a valid and active State of California Contractor’s License in the Classification of A, “General Engineering Contractor,” C-34 “Pipeline Contractor,” or C-42 “Sanitation System Contractor” to perform pipeline replacement operation using pipe bursting.
The Contractor must submit specific technical data with complete information on the physical properties of the pipe and pipe dimensions pertinent to the job. A certificate of compliance with project specifications or City-approved alternative shall be furnished for all materials to be supplied.
Manufacturer’s recommendations for handling, storage, and repair of pipe and damaged fittings shall also be included.
Complete calculations including lists of parameters, all formulas, and other data showing the design of the pipeline shall be submitted. Detailed drawings and written descriptions of the entire construction procedure to install the pipeline, bypass flow, pit sizes, pit construction and shoring, dewatering, and lateral reconnections should also be submitted for review and approval by the City. Refer to the IPBA- NASSCO Guideline Specification for the Replacement of Mainline Sewer Pipes By Pipe Bursting for further information.
4.7 Cured-In-Place Pipe
Cured-In-Place Pipe (CIPP) liner for the rehabilitation of pipelines shall be either the Type A -inversion process in compliance with ASTM F 1216 or the Type B - pull-in-place process in compliance with ASTM F 1743 for installation using heated-water cure. The CIPP liner shall use an approved polyester, epoxy or epoxy-vinyl ester-resin-impregnated flexible fabric tube. The tube is installed by an inversion method using a hydrostatic head or by pulling it through an existing pipe and inflating by inverting a membrane using a hydrostatic head. Please refer to the Standard Specification for Public Works Construction – Latest Edition (Greenbook) Section 500-5.5.1 for further information.
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Chapter 5 Technical Specifications
The City of Downey hereby adopts the “Greenbook”, Standard Specifications for Public Works Construction, latest edition plus latest supplements, as the specifications to be used to establish standards of work, material, and construction procedures for improvements to the sanitary sewer collection system within its boundaries.
This section shall be used in conjunction with the entire text of the Greenbook. Specific exceptions, clarifications, highlighted requirements, and modifications to the Greenbook are specified herein. In addition the City has Standard Specifications; see Table 5-1. These City Standard Specifications will be included as part of the bid package. Copies of these City Standard Specifications are included for reference in Appendix B. If in conflict, the requirements of this document shall take precedence over the Greenbook.
Table 5-1: City Standard Specifications Index
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Section Description
01010 Summary of Work
01025 Measurement and Payment
01100 Stormwater Runoff
01200 Construction Surveying
01570 Traffic Control
01600 Material and Equipment
01650 Mobilization
02050 Equipment, Piping, and Materials Demolition
02060 Maintenance of Existing Utilities
02210 PCC Removals
02215 Excavation and Backfill
02220 Structure Earthwork
02750 Asphalt Concrete and Portland Cement Concrete Pavement 02763 Traffic Striping
03000 Concrete
03201 Concrete Reinforcement
03260 Concrete Joints and Waterstops
03300 Below Grade Concrete Structures
03345 Concrete Finishing, Curing, and Waterproofing
03393 Concrete Sealer and Hardener
03461 Precast Reinforced Concrete Manholes and Manhole Bases 08300 Sealants and Caulking
09880 Polyvinyl Chloride Plastic Liners for Wet Well Manhole and Overflow Manhole 11000 Equipment General Provisions
11060 Pumping Equipment
11100 Testing and Startup
11200 Structural Steel and Miscellaneous Metalwork
11300 Basic Materials and Methods
11400 Hangers and Supports
11500 WellWasherUSA System
11600 Hatch Doors
14043 Leakage and Infiltration Testing of Non-Pressure Pipelines 14050 Force Main Polyvinyl Chloride (PVC) Pipe
14058 Installation of Gravity Sewer Pipelines
14059 Vitrified Clay Pipe and Associated Materials
14100 Existing Facilities
14101 Coordination and Project Requirements
14102 Project Record Documents and Contract Closeout
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14103 Construction Facilities, Temporary Controls, and Signs 14104 Clearing, Grubbing, and Restoration
14105 Trenching, Backfilling and Compacting
14107 Pressure Testing of Force Main
14108 Installation of Pressure Pipelines
14111 Valves
14113 Quality Control and Testing Laboratory Services
14114 Cured-In-Place Pipe (CIPP)
16050 Basic Electrical Materials and Methods
16110 Raceways
16120 Conductors
16195 Electrical Identification
16450 Grounding
16480 Motor Control Centers
16500 Lighting
16600 30KVA Step Down Transformer
ADD THE FOLLOWING TO SECTION 2-11 – INSPECTION
The Contractor shall request inspection at least two (2) working days in advance of any work to be done in order that inspection services may be provided. Inspection shall be scheduled based on the availability of City staff. No inspections shall be made on weekends, City holidays, or outside normal City working hours (7:30am – 5:30pm, Monday – Friday), unless approved by the Director of Public Works or an authorized representative.
ADD THE FOLLOWING TO SECTION 5-2 – PROTECTION
Whenever existing sewer mains, manholes, force mains, or other piping or appurtenances are encountered in or near the lines of trenches being excavated, the Contractor shall be required to use proper care in preserving the same intact, and will be held responsible for any damage to the existing facilities during the progress of work.
ADD THE FOLLOWING TO SECTION 7-5 – PERMITS
The permittee shall be responsible for providing California Environmental Quality Act (CEQA) compliance and obtaining all permits necessary to complete the work. All work in existing City streets or right-of-way will require the Contractor to obtain an encroachment permit.
ADD THE FOLLOWING TO 201-1.4.1 – CONCRETE MIXING, General Job mixing of concrete will not be allowed. Concrete will not be accepted without a stamped batch ticket by the weight master. Concrete shall be deposited by truck or hopper only; use of other hand buckets is not acceptable.
ADD THE FOLLOWING TO 207-8.2.2 – VITRIFIED CLAY PIPE, Dimensions and Tolerance Pipe ends shall be perpendicular to the longitudinal axis. The socket shall be true, circular, and concentric with the barrel of the pipe within the allowable tolerances specified in the subsection. The ends of the pipe shall be so formed that when the pipes are laid together and the joints made, they shall constitute a continuous and uniform line of pipe and shall have a smooth and regular interior surface.
ADD THE FOLLOWING TO 306-1.2.2 – PIPE LAYING
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Sewer main shall be installed in a dry excavation at the required line and grade. Care shall be taken when installing the pipe zone material with proper support of the pipe under the haunches and bells to avoid vertical or circumferential deflection of the pipe. Care shall be taken when moving the trench shield, if used, and when backfilling the pipe zone to avoid movement of the pipe.
ADD THE FOLLOWING TO THE SECTION 306-1.4 – TESTING PIPELINES Sewer main testing shall consist of the following tests:
· Video Inspection Test
· Air Pressure Test
· Deflection Test (PVC pipe only)
· Manhole Negative Air Pressure Test After Backfill (Vacuum Test) (ASTM C-1244M-93) · Water Infiltration Test (discretionary)
· Force Main Pressure Test (at site specific test pressure) Testing shall proceed after compaction is complete and dry utilities are in place, but prior to placing of permanent resurfacing. All pipes are to be clean and empty at the time of testing.
ADD THE FOLLOWING NEW SECTION 306-1.4.4.1 – AIR PRESSURE TEST FOR VCP SEWER PIPE For all Vitrified Clay Pipe, a low pressure air test shall be conducted in accordance with the following test procedure and the procedures outlined in the Low Pressure Air Test for Sanitary Sewers as published by the National Clay Pipe Institute (NCPI) (ANSI/ASTM C-828, Standard Test Method for Low-Pressure Air Test of Vitrified Clay Pipe Lines). All necessary test equipments shall be furnished by the Contractor and the test shall be made only after the line has been properly installed, including any necessary test fittings, and backfilled.
Test plugs shall be carefully placed at each end of the section of the line to be tested. When all necessary equipment is in place, a compressed air supply shall be attached within the line and the pressure increased to four (4) pounds per square inch (psi). After the air supply is securely turned off or disconnected, there shall be a two minute waiting period to allow stabilization of air within the sewer line before the actual test period begins. Air may be added only to maintain a pressure of 4 psig. When the internal pressure decreases to 3.5 psig, timing shall start and the seconds counted until the pressure has decreased to 2.5 psig.
Minimum permissible pressure holding times for sewer main, with or without laterals, are listed in the NCPI Air Test Tables, as published in the latest “Low Pressure Air Test for Sanitary Sewers (Procedures and Tables)”. The maximum length of a line that may be tested at one time shall be 500 feet or the length between two adjacent manholes. After completion of the test, the air pressure shall be released slowly through the valve. Air test plugs shall not be removed until the air pressure is no longer measurable.
ADD THE FOLLOWING NEW SECTION 306-1.4.5.1 – FORCE MAIN TEST PRESSURE Upon the completion of the laying, jointing, and backfilling but before the final pavement, the force main pipeline or portions thereof shall be hydrostatically tested. The lines shall be bulk headed and tested in sections. The bulkheads used for testing shall be of adequate design and construction to withstand the required pressures without causing injury to the pipe.
The test pressure at the location of the testing equipment shall be computed on the basis of the relative elevation of the test gauge and the lowest point in the section being tested, and shall result in a pressure of not more than 150 percent of design pressure at the lowest point in said section. The test pressure at the highest point in the test section shall be not less than 125 percent of design pressure. For ductile-iron pipe force mains the minimum test pressure shall be at least 200 psi. The test pump and gauge shall be connected to the force main at a location other than the highest point in the line to facilitate release of air from the high point. A recording gauge shall be used.
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Prior to testing, written confirmation of design and test pressure shall be provided from the design engineer of record to confirm that the pressure rating of the pipe material, fittings, and restraint system will not be exceeded.
This test shall be made on all sections of the force main in order that all pipe, valves, and fittings may receive the test. The test pressure shall be maintained continuously by pumping for a period of at least one hour. At the end of the first hour, the pressure shall meet the requirements stated above. Pumping shall then be discontinued for one hour and drop in pressure read on the dial of the gauge at the end of the second hour recorded. The initial test pressure shall then be restored by pumping, and the quantity of water pumped into the line to accomplish this shall be measured accurately. No standard allowance for leakage will be allowed. A standard allowance recommended by the pipe manufacturer may be submitted for review and consideration. If there is any sign of leakage or failure at any point on the line during the test, the test shall be discontinued until the same has been repaired, after which the test shall be repeated until the section tested shall have met the above requirements. The testing shall be done in front of the City inspector.
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Chapter 6 Standard Drawings
The City has adopted the “Standard Plans for Public Works Construction” (Greenbook), latest edition plus any supplements, as the standard drawings to be used. These drawings were promulgated by the “Greenbook” Committee of Public Works Standards, Inc. Copies of these drawings are included for reference in Appendix C.
Additionally, five standard drawings (1-S through 1-5) created by the City are included in this section.
The City reserves the right to create additional standard drawings in the future.
Table 6-1: Standard Drawing Index
Drawing Number Title
1-S Standard Sewer Notes for Construction
2-S Standard Sanitary Sewer Materials
3-S Standard Sewer Legend and Abbreviations
4-S Sample Title Block for Construction Drawings
5-S Sanitary Sewer Trench and Paving
Greenbook 200-4 Precast Concrete Sewer Manhole
Greenbook 201-3 Precast Concrete Shallow Manhole
Greenbook 202-2 Drop Sewer Manhole
Greenbook 204-3 Terminal Cleanout Structure
Greenbook 205-3 Sewer Manhole Adjustment
Greenbook 206-2 Manhole Raising Rings
Greenbook 207-3 Precast Reinforced Concrete Manhole Base Greenbook 208-3 Breaking Into Existing Manholes
Greenbook 210-4 24” Manhole Frame and Cover (Locking type) Greenbook 211-3 Manhole Frame and Cover (Pressure Type) Greenbook 212-3 Anchor System for Pressure Cover
Greenbook 220-4 Chimneys
Greenbook 221-2 Pipe Anchors and Backfill Stabilizers
Greenbook 222-2 House Connection Sewer (Sewer Lateral)
Greenbook 223-3 House Connection Remodeling
Greenbook 224-3 Supports for Conduits Across Trenches
Greenbook 225-3 Blanket Protection for Pipes
Greenbook 630-5 600 mm (24”) Manhole Frame and Cover
Greenbook 636-3 Polypropylene Plastic Step
Appendix A - Permit Application Forms
Permit Application Form
Date:
www.downeyca.org
Single-Family Residential Multi-Family Residential Commercial Industrial Demolition Site Address APN#
Property Owner’s Name
Mailing address
Phone # Email:
Licensed Contractor License Class & Number
Mailing Address
Phone # Email:
Applicant Contact (If different from above)
Mailing Address
Phone # Email:
Description of Work:(additional space on back)
Structures Sq.Ft. Reroofs Squares Qty Signs Sq.Ft.
NEW Comp. Shingle Wall
Addition Light Weight Tile Monument
Alter/Remodel Cement Tile Pole
Garage Built-up Repairs
Carport Metal/Other Drywall/Insulation
Tenant Improvement Tear off? Yes No Sandblast Demolition Stucco/Siding
Accessory Structures Walls/Fences Sq.Ft Stone Veneer
Guest Room/Rec Room Masonry Aluminum Siding
Cabana Wood
Storage/Shed Wrought Iron Flatwork
Reframe Roof Pilasters w/ Wrought Iron Driveway
Other Vinyl Walkway
Patios/Porches Other/Temp Concrete Slab
Wood Cover Change-Outs Qty Pools
Metal Cover Window-Replacement Vinyl
Enclosure Doors Gunite/Replaster
Awnings Fireplaces Fiberglass
Canopies Masonry Spas Qty
Decks Prefab Spa/Hot Tub
Balconies BBQ Sauna
**Turn page over for Electrical, Mechanical, and Plumbing Information**
Electrical QTY Mechanical QTY Plumbing QTY
Lights/Switches/Receptacles FAU/Heater (install, alter, relocate) Fixtures (install, alter, relocate) Light Fixtures Up to 100,000 BTU’s Bathrooms
Switches 100,001 – 1,000,000 BTU’s Bathtub
Outlets/J-Boxes Over 1,000,000 BTU’s Bidet
Meters Refrigeration, Compressor, Absorption Unit Shower Service Panel(s) Up to 100,000 BTU’s Sink
Amps: 100,001 – 500,000 BTU’s Toilet(s)/ Water Closet Sub-Panel(s) Over 500,000 BTU’s Tub/Shower Combination Amps: Air Handling Units Urinal
Appliances Up to 2,000 CFM 1-10 Kitchen/ Laundry Rooms New Residential-Dwelling (Sq.Ft.) HVAC 2,000 CFM 11 or more Bar Sink New Residential-Garage (Sq.Ft.) HVAC 2001 -10,000 CFM Dishwasher Clothes Dryer HVAC 10,001 CFM or more Garbage Disposal Dishwasher Miscellaneous Kitchen Sink
Electric Range Air Supplies & Returns Laundry Tub
Exhaust Fan (Kitchen or Bath) Evaporative Cooler Washing Machine Furnace Garage Ventilation System Water Heaters/ Softeners Garbage Disposal Ventilation Fans Solar Water Heater Oven Commercial Kitchen Hoods Water Heater and/or Vent(s) Space Heater Spray Booths (or similar) Water Filtration Equipment Water Heater Fire Damper Commercial/ Industrial
Welder, Transformer, or Generator Hood: Type 1 Type 2 Drinking Fountain Res Swimming Pool Product Conveying System Floor Drain Pre fab/Spas/ Hot Tub Floor Sink
Residential Up to 3 HP Non kitchen Industrial Interceptor Commercial 1-10 HP Sewer QTY Miscellaneous
Commercial 11-50 HP SFR Sewer Connection Backflow Prevention Device Commercial 51-100 HP Connect Addt’l Bldg to Res Sewer Earthquake Gas Shut-Off Valve Appliances over 100 or more HP Connect Res Sewer to Private Sys. Res Gas Piping Outlets Poles & Signs Chemical Waste System Commercial Gas Piping Outlets Temp Service Power Pole Drainage/ Backwater Valve Hose Bibb/ Vacuum Breaker(s) Temp Sub-Pole House Sewer Manhole Lawn Sprinkler Valve(s) Temp Distribution System Grease Interceptor Main Water Line-up to 1 ½ inch Temp Lighting, Booths, Displays Grey Water System Main Water Line- 2 to 3 inch Temp Generators & Rides Septic/ Private Installation or Alter Main Water Line –3 inch or larger Sign w/1 Branch Circuit Sewer Cap, Disconnect, Re-pipe System-each fixture Power Apparatus/Branch Circuits Repair/ Alter Drain/ Vent Pipe(s) 15-20 Amp/ 1-120 Volt Circuits Roof Drain(s)
15-20 Amp/ Greater than 120 Volt
Circuits
Storm-water Retention System
Misc. Conduits & Conductors Swimming Pool System
Ansel System
SOLAR Photovoltaic 1-10Kva
SOLAR Photovoltaic 10kva greater
Description of work continued
__________________________________________________________________________________________________ __________________________________________________________________________________________________ __________________________________________________________________________________________________ __________________________________________________________________________________________________ __________________________________________________________________________________________________ __________________________________________________________________________________________________
Submit Enchroachment Permit with Public Works
APPLICANT INFORMATION:
Job Location: (*R)
Property Owner: (*R)
Address: (*R)
City: (*R) State ** Please Select **ZIP
Phone Number: (*R) Cell Number
Email: (*R)
CONTRACTOR INFORMATION:
Name: (*R)
Address: (*R)
City : (*R) State : (*R) ZIP : (*R)
Phone: (*R) Cell Number
Email: (*R)
State License
Number: (*R)
License Class License Expiration Date
Contractor City
License Number: (*R)
USA Ticket Number
REFUNDABLE DEPOSIT:
Refundable Deposit
Amount
Depositor
Address
City State ZIP
Phone Number Cell Number
Email
DESCRIPTION OF WORK:
Description Of Work
ADDITIONAL INFORMATION:
Two Sets Of Construction
Plans Upload
Upload Construction Plans(PDF Only) Choose File No file chosen Two Sets Of Traffic
Plans Upload
Upload Traffic Plans(PDF Only) Choose File No file chosen
CONTRACTORS PERFORMING WORK WITHIN THE PUBLIC RIGH OF WAY OTHER THA
THE GENERAL CONTRACTOR SHALL PULL A RIDER PERMIT PRIOR TO START OF WOR Permit Hnadler
information Required
Permit Handler Phone (*R)
Permit Handler Email (*R)
UPLOAD REQUIRED:
You are not signed-in.Sign In
*GENERAL LIABILITY INSURANCE WITH THE CITY OF DOWNEY AS
ADDITIONALLY INSURED AND CERTIFICATE HOLDER WITH APPLICABLE ENDORESEMENTS
General Liability Insurance Choose File No file chosen
State Of California
Contractors License Pocket Card Choose File No file chosen SIGNATURE:
*I UNDERSTAND AND AGREE TO THE CONDITIONS AND REQUIREMENTS OF THIS APPLICATION FOR PERMIT.
Signature Name: (*R) Phone Number : (*R) Cell Number Parkway Width Sub Reference
SUBMIT CANCEL
Copyright © 2020 Downey, CA. All rights reserved.
You are not signed-in.Sign In
DOC 338126v6 (12/2021)
FORM A: APPLICANT QUESTIONNAIRE
Name Of Company
Company Contact Name
Company Contact E-mail Phone Number
Reason for Submittal – New Permit Permit Revision Permit Amendment Permit Renewal Please check () only one box above and complete the corresponding questions below.
1. New Permit (for new companies and for changes in ownership)
Type of business
Is the facility: New or Existing (please check)
If existing, previous company name
Type of business
Industrial Wastewater Discharge Permit No.
Provide a description of all manufacturing processes and wastewater producing operations in an attachment.
Are any changes being made to the facility’s existing wastewater pretreatment/conveyance systems? Yes No If yes, briefly explain these modifications in attachments.
Is there more than one company discharging industrial wastewater at your facility? Yes No If yes, provide for each company its name, a separate address and a description of its operations. If feasible, each company must apply for a separate permit and must have its own incoming water meter and a separate industrial wastewater sampling point.
If your facility will involve a new connection to the public sewer, please check the point of connection:
Local city sewer, Sanitation Districts’ Trunk sewer.
If you are relocating, and had a previous Industrial Wastewater Discharge Permit, give your previous address , and permit number .
If you have received a temporary permit, give permit number .
All submittals for new permits must include a permit application, plans (if changes have occurred) and pertinent supporting information.
2. Revision of Existing Permit (for a 25 percent or more change in wastewater quantity/quality) Permit number .
Has your wastewater quantity and/or quality changed over 25 percent? Yes No If yes, documentation addressing the magnitude and reason(s) for the change must be submitted. If no, a revision is not required at this time.
Have there been any changes in production processes, wastewater pretreatment systems or sewerage plumbing? Yes No If yes, submit plans and describe these changes in attachments.
All submittals for a revised permit must include a permit application, plans (if changes have occurred) and supporting information.
3. Amendment to Permit (for modifications to the wastewater conveyance/pretreatment system) Permit Number .
Attach a brief summary of the existing conditions and the proposed changes.
All submittals for a permit amendment must include plans and supporting information. Applicant must also answer the questions on the next page.
DOC 338126v6 (12/2021)
4. Permit Renewal (for permits with expiration dates)
Permit Number .
Have there been any changes in production processes, wastewater pretreatment systems or sewerage plumbing? Yes No If yes, submit plans and describe these changes in attachments.
All submittals for a permit renewal must include a permit application, plans (if changes have occurred) and supporting information.
Supporting Information Required
All submittals must include the following forms, which are included in Appendix 6.1:
Form A - Applicant Questionnaire
Form B - Calculation of Industrial Wastewater Discharge Flow Rate Form C - Tank Schedule and Spill Containment Calculations Form D - Check List
Furthermore, your company must answer the questions below to determine the additional supporting information that must be provided:
1. Waste Minimization (refer to Sections 2.4 and 3.3 E) Please describe below or in an attachment all of your company’s existing/proposed pollution prevention measures (e.g., reuse, product reformulation, process changes, housekeeping measures, etc.):
Has your company previously submitted a waste minimization plan to the Districts? Yes No If no, please read Sections 2.4 and 3.3E and submit the appropriate plan (if applicable). Your company is encouraged to obtain information on source reduction measures and options for your industrial processes by calling the Sanitation Districts’ Industrial Waste Section at (562) 908-4288, ext. 2900.
2. Wastewater Quality (refer to Sections 3.3G and H)
Please provide the results of at least two 24-hour composite analyses attesting to concentrations of chemical oxygen demand, suspended solids and any priority or regulated pollutants that may be found in your wastewater. Your company must also provide material safety data sheets of all chemicals used in the facility that may directly or indirectly contaminate your wastewater.
3. New Equipment (refer to Sections 3.3 F, J and K)
Is your company installing new pretreatment, monitoring, conveyance or industrial equipment that may have an impact on the quality or quantity of your wastewater? Yes No If yes, please provide catalog cuts of all units and important details such as: number of units, sizes, hours of operation, pump rating curves, operating parameters, etc.
4. Baseline Monitoring Report (refer to Sections 2.1 and 3.3 I) Does your company currently fall under one of EPA’s categories? Yes No If yes, your company must submit a Baseline Monitoring Report, unless it was submitted one in the past and there have been no changes in operations that may change your categorical standards.
5. Rainwater Management (refer to Section 3.2)
Are there any outdoor drains, trenches or sumps at your facility that are connected to the sewerage system? Yes No
If yes, your company must submit plans and information that describe the existing means to divert rainwater from the sewerage system or a proposal to comply with the Districts’ rainwater guidelines.
Please be informed that new automatic rainwater diversion systems will not be approved unless the applicant proves that this is the only feasible alternative.
FORM C: TANK SCHEDULE & SPILL CONTAINMENT CALCULATIONS
Please complete one form for each containment area (make additional copies if necessary).
TANK I.D.
NUMBER
TANK
NAME
TANK
DIMENSIONS1
TANK
CONTENTS pH IS TANK
ELEVATED2
1 Specify height and diameter if tank is round; or length, width and height if tank is rectangular.
2 If the tank is elevated above the ground on legs, specify the location (elevation) of the bottom of the tank. If the tank is located on a pad or solid platform, specify dimensions of the pad or platform.
1 1
2 2
2 2
1 2
1 1
2. Spill Containment Calculations (make additional copies if necessary).
Answer the following questions:
Check One
a) If this is your company’s first permit submittal to the Districts, do you store hazardous or restricted materials? YES NO
b) Does your company currently have tanks/equipment with hazardous or restricted solutions that lack adequate spill containment? YES NO
c) Is your company proposing any additions/modifications of tanks or equipment that will need spill containment? YES NO
If the answer to any of the questions above is “YES,” your company must submit plans that describe and propose an adequate spill containment system and must complete the calculations below:
1. Containment Volume Required:
The required containment volume is equal to the capacity of the largest tank containing a solution that requires containment plus the volume of six inches of rain over the containment area (if the area is not roofed).
= Volume of largest tank (assumed to spill) + volume of 6 inches of rain over contain area (if area is outdoors)
= +
= (specify units)
2. Containment Volume Provided:
The containment provided is equal to the volume of the dike, berm, sump or other containment structure minus the volume displaced by tanks, pads and other equipment within the containment area.
= Volume of containment dike - volume displaced by tanks and other equipment
= ⎯
= (specify units)
Subtract from
⎯ = (must be greater than zero to satisfy spill containment requirements)
Note: All drains, sumps and associated plumbing within spill containment areas must be clearly shown on submitted drawings.
$
SEWERAGE SYSTEM CONNECTION FEE
(562) 908-4288, extension 2727
Website: www.lacsd.org
Email: [email protected]
Hours: 7:30 a.m. – 4:00 p.m., M – Th
7:30 a.m. – 3:00 p.m., Friday
District No: ___________ (FOR DISTRICTS’ USE ONLY) Complete Items 1 through 10 – PLEASE TYPE OR PRINT
Date:
1. Property Owner(s):
2. Business or Project Name (Commercial Parcels Only):
3. Address of Property:
(STREET ADDRESS, CITY, STATE & ZIP CODE)
4. Contact Person: Phone Number: ( ) (FIRST AND LAST NAME)
5. Mailing Address:
(IF DIFFERENT FROM ABOVE) (STREET ADDRESS, CITY, STATE & ZIP CODE)
6. County Assessor Map Book, Page, and Parcel Number (APN): - -
7. Structure is: Proposed (New Construction) Existing (Tenant Improvement) Existing (Septic to Sewer)
8. User Category and Units of Usage: (Check the appropriate box and provide the applicable information to the right) a. RESIDENTIAL:
Single Family Home(s) ADU /J-ADU Tract # Lot(s) ► Number of New Units:
Multi-Unit Residential (Apartments, Duplex, Triplex, etc.) Mobile Home Park
Condominium/Townhome
► Number of New Units:
b. COMMERCIAL:
Hotel/Motel ► Number of Rooms:
Convalescent Hospital / Home for the Aged ► Number of Beds:
Other (Specify): ► Improvement Sq. Ft:
c. INSTITUTIONAL: College/University ► Number of Students:
Private School
Church ► Improvement Square Footage:
d. INDUSTRIAL: All Categories ► All industrial dischargers must obtain a permit for Industrial Wastewater discharge.
9. In order to process this application an architectural site and floor plan must be submitted (any size). This is not required for conversion from septic tank to sewer connection or for new single-family homes.
10. I certify that the information provided in this application is true and correct to the best of my knowledge.
(Signature) (Date)
OWNER
AGENT FOR OWNER
Please pay by check or money order. We also accept VISA, MasterCard, American Express or Discover. Fee applies to payments made using debit and credit cards.
Make checks payable to: COUNTY SANITATION DISTRICTS OF LOS ANGELES COUNTY Returned checks will be subject to penalty.
(FOR DISTRICTS’ USE ONLY)
FEE CALCULATION FOR RESIDENTIAL, COMMERCIAL AND INSTITUTIONAL CATEGORIES X =
Number of Units of Usage Connection Fee per Unit of Usage Connection Fee - Subtotal
__
-FEE PAYME
Connection Fee - Total
From: D.C. Yes No Processed by:
Amount: $ _________________________ Check No. __________________ Approval Date: _________________ Approved by:
$ $
SPECIAL CREDITS (only if applicable)
DEMOLITION CREDIT*
CHANGE IN USE CREDIT*
Annexation Date:
* In order to receive credit, proof of
demolition or former use must be
submitted with your application
(e.g. Demolition Permits, Original
Plans, or Demolition Plan). $
SEWAGECATEGORY UNIT OF USAGE UNITSSingle Family Home Parcel 1.00 185.00 189.00 193.00 197.00Condominiun Unit 0.75 138.75 141.75 144.75 147.75Multi-Unit Residential Unit 0.60 111.00 113.40 115.80 118.20Mobile Home Park Space 0.60 111.00 113.40 115.80 118.20Hotel/Motel/Rooming House Room 0.47 86.95 88.83 90.71 92.59Store 1000 Sq.Ft. 0.38 70.30 71.82 73.34 74.86Supermarket 1000 Sq.Ft. 1.34 247.90 253.26 258.62 263.98Shopping Center1000 Sq.Ft. 1.92 355.20 362.88 370.56 378.24Regional Mall 1000 Sq.Ft. 1.22 225.70 230.58 235.46 240.34Office Building 1000 Sq.Ft. 0.75 138.75 141.75 144.75 147.75Medical, Dental, Veterinary Clinic 1000 Sq.Ft. 1.12 207.20 211.68 216.16 220.64Restaurant 1000 Sq.Ft. 8.80 1,628.00 1,663.20 1,698.40 1,733.60Indoor Theatre 1000 Sq.Ft. 0.47 86.95 88.83 90.71 92.59Car Wash - Tunnel, No Recycling 1000 Sq.Ft. 13.78 2,549.30 2,604.422,659.54 2,714.66Car Wash - Tunnel, Recycling 1000 Sq.Ft. 10.15 1,877.75 1,918.35 1,958.95 1,999.55Car Wash - Wand 1000 Sq.Ft. 2.61 482.85 493.29 503.73 514.17Bank, Credit Union 1000 Sq.Ft. 0.38 70.30 71.82 73.34 74.86Service Shop, Auto Maint/Repair1000 Sq.Ft. 0.38 70.30 71.82 73.34 74.86Animal Kennel 1000 Sq.Ft. 0.38 70.30 71.82 73.34 74.86Gas Station 1000 Sq.Ft. 0.38 70.30 71.82 73.34 74.86Auto Sales 1000 Sq.Ft. 0.38 70.30 71.82 73.34 74.86Wholesale Outlet 1000 Sq.Ft. 0.38 70.30 71.82 73.34 74.86Nursery/Greenery 1000 Sq.Ft. 0.10 18.50 18.90 19.30 19.70Manufacturing 1000 Sq.Ft. 1.17 216.45 221.13 225.81 230.49Light Manufacturing 1000 Sq.Ft. 0.15 27.75 28.35 28.95 29.55Lumber Yard 1000 Sq.Ft. 0.15 27.75 28.35 28.95 29.55Warehousing 1000 Sq.Ft. 0.15 27.75 28.35 28.95 29.55Open Storage 1000 Sq.Ft. 0.15 27.75 28.35 28.95 29.55Drive-In Theatre 1000 Sq.Ft. 0.08 14.80 15.12 15.44 15.76Night Club 1000 Sq.Ft. 1.30 240.50 245.70 250.90 256.10Bowling/Skating 1000 Sq.Ft. 0.99 183.15 187.11 191.07 195.03Club & Lodge Halls 1000 Sq.Ft. 0.46 85.10 86.94 88.78 90.62Auditorium/Amusement 1000 Sq.Ft. 1.30 240.50 245.70 250.90 256.10Golf Course & Park 1000 Sq.Ft. 0.38 70.30 71.82 73.34 74.86Campground, Marina, RV Park Space 0.24 44.40 45.36 46.32 47.28Convalescent Home Bed 0.47 86.95 88.83 90.71 92.59Horse Stable Stall 0.15 27.75 28.35 28.95 29.55Laundromat 1000 Sq.Ft. 14.24 2,634.40 2,691.36 2,748.32 2,805.28Mortuary/Funeral Home 1000 Sq.Ft. 0.89 164.65 168.21 171.77 175.33Health Spa without Showers 1000 Sq.Ft. 1.12 207.20 211.68 216.16 220.64Health Spa with Showers 1000 Sq.Ft. 2.24 414.40 423.36 432.32 441.28Special Event Center* Person in Attendance 0.03 5.55 5.67 5.79 5.91College/University Student 0.08 14.80 15.12 15.44 15.76Private School 1000 Sq.Ft. 0.75 138.75 141.75 144.75 147.75Library/Museum 1000 Sq.Ft. 0.38 70.30 71.82 73.34 74.86Post Office (Local) 1000 Sq.Ft. 0.38 70.30 71.82 73.34 74.86Post Office (Regional) 1000 Sq.Ft. 0.15 27.75 28.35 28.95 29.55Church 1000 Sq.Ft. 0.18 33.30 34.02 34.74 35.46A = 0.3049 B = 0.3348 C = 0.3603DOC 4639002* Including, but not limited to, Convention Center, Fairground, Racetrack, Sports Stadium/ArenaADOPTED RATESANITATION DISTRICT NO. 2SERVICE CHARGE LOADINGS, SEWAGE UNITS, AND UNIT RATESFISCAL YEARS 2022-23 THROUGH 2025-26FY 22/23 FY 23/24 FY 24/25 FY 25/26
SEWAGECATEGORY UNIT OF USAGE UNITSSingle Family Home Parcel 1.00 185.00 188.00 191.00 194.00Condominiun Unit 0.75 138.75 141.00 143.25 145.50Multi-Unit Residential Unit 0.60 111.00 112.80 114.60 116.40Mobile Home Park Space 0.60 111.00 112.80 114.60 116.40Hotel/Motel/Rooming House Room 0.47 86.95 88.36 89.77 91.18Store 1000 Sq.Ft. 0.38 70.30 71.44 72.58 73.72Supermarket 1000 Sq.Ft. 1.34 247.90 251.92 255.94 259.96Shopping Center1000 Sq.Ft. 1.92 355.20 360.96 366.72 372.48Regional Mall 1000 Sq.Ft. 1.22 225.70 229.36 233.02 236.68Office Building 1000 Sq.Ft. 0.75 138.75 141.00 143.25 145.50Medical, Dental, Veterinary Clinic 1000 Sq.Ft. 1.12 207.20 210.56 213.92 217.28Restaurant 1000 Sq.Ft. 8.80 1,628.00 1,654.40 1,680.80 1,707.20Indoor Theatre 1000 Sq.Ft. 0.47 86.95 88.36 89.77 91.18Car Wash - Tunnel, No Recycling 1000 Sq.Ft. 13.78 2,549.30 2,590.642,631.98 2,673.32Car Wash - Tunnel, Recycling 1000 Sq.Ft. 10.15 1,877.75 1,908.20 1,938.65 1,969.10Car Wash - Wand 1000 Sq.Ft. 2.61 482.85 490.68 498.51 506.34Bank, Credit Union 1000 Sq.Ft. 0.38 70.30 71.44 72.58 73.72Service Shop, Auto Maint/Repair1000 Sq.Ft. 0.38 70.30 71.44 72.58 73.72Animal Kennel 1000 Sq.Ft. 0.38 70.30 71.44 72.58 73.72Gas Station 1000 Sq.Ft. 0.38 70.30 71.44 72.58 73.72Auto Sales 1000 Sq.Ft. 0.38 70.30 71.44 72.58 73.72Wholesale Outlet 1000 Sq.Ft. 0.38 70.30 71.44 72.58 73.72Nursery/Greenery 1000 Sq.Ft. 0.10 18.50 18.80 19.10 19.40Manufacturing 1000 Sq.Ft. 1.17 216.45 219.96 223.47 226.98Light Manufacturing 1000 Sq.Ft. 0.15 27.75 28.20 28.65 29.10Lumber Yard 1000 Sq.Ft. 0.15 27.75 28.20 28.65 29.10Warehousing 1000 Sq.Ft. 0.15 27.75 28.20 28.65 29.10Open Storage 1000 Sq.Ft. 0.15 27.75 28.20 28.65 29.10Drive-In Theatre 1000 Sq.Ft. 0.08 14.80 15.04 15.28 15.52Night Club 1000 Sq.Ft. 1.30 240.50 244.40 248.30 252.20Bowling/Skating 1000 Sq.Ft. 0.99 183.15 186.12 189.09 192.06Club & Lodge Halls 1000 Sq.Ft. 0.46 85.10 86.48 87.86 89.24Auditorium/Amusement 1000 Sq.Ft. 1.30 240.50 244.40 248.30 252.20Golf Course & Park 1000 Sq.Ft. 0.38 70.30 71.44 72.58 73.72Campground, Marina, RV Park Space 0.24 44.40 45.12 45.84 46.56Convalescent Home Bed 0.47 86.95 88.36 89.77 91.18Horse Stable Stall 0.15 27.75 28.20 28.65 29.10Laundromat 1000 Sq.Ft. 14.24 2,634.40 2,677.12 2,719.84 2,762.56Mortuary/Funeral Home 1000 Sq.Ft. 0.89 164.65 167.32 169.99 172.66Health Spa without Showers 1000 Sq.Ft. 1.12 207.20 210.56 213.92 217.28Health Spa with Showers 1000 Sq.Ft. 2.24 414.40 421.12 427.84 434.56Special Event Center* Person in Attendance 0.03 5.55 5.64 5.73 5.82College/University Student 0.08 14.80 15.04 15.28 15.52Private School 1000 Sq.Ft. 0.75 138.75 141.00 143.25 145.50Library/Museum 1000 Sq.Ft. 0.38 70.30 71.44 72.58 73.72Post Office (Local) 1000 Sq.Ft. 0.38 70.30 71.44 72.58 73.72Post Office (Regional) 1000 Sq.Ft. 0.15 27.75 28.20 28.65 29.10Church 1000 Sq.Ft. 0.18 33.30 33.84 34.38 34.92A = 0.3049 B = 0.3348 C = 0.3603DOC 4639002* Including, but not limited to, Convention Center, Fairground, Racetrack, Sports Stadium/ArenaADOPTED RATESANITATION DISTRICT NO. 18SERVICE CHARGE LOADINGS, SEWAGE UNITS, AND UNIT RATESFISCAL YEARS 2022-23 THROUGH 2025-26FY 22/23 FY 23/24 FY 24/25 FY 25/26
Appendix B - City Standard Specifications
GENERAL NOTES - SEWER
SANITARY SEWER MATERIALS
CURED-IN-PLACE PIPE
DIVISION 1 – GENERAL REQUIREMENTS
SECTION 01010 - SUMMARY OF WORK
PART 1 - GENERAL
1.01 CONTRACT LIMITS
The work shall involve the following project locations/areas:
A. Project Location
B. Pertinent on-site work.
1.02 WORK TO BE DONE BY CONTRACTOR:
The work to be performed under this Contract generally consists of the reconstruction of 4-inch Green SDR- 35 PVC sewer lateral, construction of 8-inch Green PVC C-900, SDR-14 sewer pipe and associated fittings, construction of 48-inch diameter manhole with polypropylene steps, installation of SCH 40 PVC electrical conduit, and demolition and abandonment of existing septic tank and associated appurtenances; clearing and grubbing; trenching, backfilling and compacting; asphalt concrete (AC) pavement reconstruction; reconstruction of miscellaneous PCC improvements, landscaping, irrigation, and other existing improvements disturbed during the course of construction; traffic control; and all labor, tools, materials, equipment, and appurtenant work thereto necessary for the proper construction of the contemplated improvements, in accordance with project Plans and Specifications.
1.03 TIME LIMIT
The Contract Time shall commence on the date of issuance of the City’s written Notice to Proceed. The Contractor shall commence work within ten calendar days thereafter, and shall diligently prosecute all work under the Base Bid to completion within XXXX (XX) working days, including all materials procurement following the issuance of the Notice to Proceed.
The amount of Liquidated Damages is $1,000.00 per calendar day. This amount shall be deducted from any compensation due to the Contractor should he/she fail to complete the work required by the terms of this contract within the time specified hereinabove, plus any authorized time extensions. Material lead time is included in the number of working days. It is the responsibility of the Contractor to plan work diligently such that the critical path is not impacted by the lead time of the materials.
The aforementioned dates shall be considered inclusive of material lead time, weather delay, and coordination needs with other Contractors in the vicinity; no adjustments or time extensions shall be provided therefore.
1.04 CONSTRUCTION STAGES
The City anticipates awarding the construction contract late xxxx. The contract document will be forwarded to the Contractor for execution immediately thereafter. The Contractor shall plan and initiate the abandonment of the existing septic tank and construction of the new sewer lateral and associated piping improvements to comply with the project requirements. The Contractor shall provide a work/construction staging plan, to be approved by the City, prior to the submission of a detailed construction schedule.
1.05 NUMBER OF TRAVEL LANES:
As described in Section 01570, Traffic Control, 1.01K, Lane closures, of these Special Conditions, lane closures on Little Lake Road during daytime working hours shall be limited to 8:00 a.m. to 3:30 p.m. unless otherwise authorized by the City.
The Contractor shall be responsible for all temporary paving, removal/reconstruction of conflicting improvements, striping, traffic control, adjustments to construction sequencing and logistics, as necessary to provide said travel lane(s). The City reserves the right to direct all construction activities (including pot- holing) which create conflicts with providing said travel lane(s) to be performed on weekends or nighttime hours. Compensation for temporary improvements, weekend and nighttime work, shall be considered as included in various bid items. No additional compensations will be provided therefore.
1.06 DEFINITION OF BID ITEMS:
The unit prices and lump sum amounts to be paid for the Items listed in the Proposal shall include full compensation for furnishing all labor, materials, tools, equipment and incidentals necessary to complete the
work and for performing all work contemplated and embraced under the Contract, in accordance with the Plans and Specifications. This shall include the Contractor's costs involved with bonding, insurance, worker's compensation, overhead, financing, permit fees, testing, mobilization, traffic control, public convenience and safety, protective barricading, sanitary facilities, storage of equipment and materials, security against theft and vandalism, project site maintenance, dust control, clean-up, and all other items incidental to the work.
Payment for Unit Price work shall be made for the actual quantities of Contract Items removed, constructed, or disposed of in accordance with the Plans and these Specifications. Measurement of Unit Price work shall be as specified in Section 9-1, “Measurement of Quantities for Unit Price Work,” of the SSPWC. Payment for Lump Sum work shall be paid for at the price indicated in the Bid, in accordance with Section 9 -2, “Lump Sum Work,” of the SSPWC.
DEFINITION OF BID ITEMS
STREET IMPROVEMENTS
1. Construction Surveying
Provide construction surveying as specified in the Plans and Specifications including Special Conditions Section 01200. The work shall include furnishing all labor, materials, equipment, and other incidentals including but not limited to: hiring a California licensed land surveyor, preparing cut sheets, establishing vertical and horizontal control, grade verification, document research, survey monument protection and/or re-establishment and recordation, centerline ties, corner records, confirming proposed and final horizontal and vertical alignments, preparation of digital files, and all other associated work as necessary to perform construction surveying in accordance with the Plans and Specifications.
Full compensation for conforming to the requirements of CONSTRUCTION SURVEYING shall be made at the Contract Unit Price per Lump Sum (LS) and shall include furnishing all labor, materials, tools, equipment and incidentals required to complete the work. No additional compensation shall be allowed therefore.
Progress payments shall be pro-rated in proportion to the total value of work completed to date as a function of the total awarded contract amount.
2. Traffic Control and Pedestrian Safety (Not to Exceed 2.5% of the Total Base Bid) Provide traffic control and pedestrian safety as specified in the Plans and Specifications including Special Conditions Section 01570 and all additional Specifications and applicable standards including but not limited to Subsection 7-10, “Public Convenience and Safety,” of the SSPWC, the California Manual of Uniform Traffic Control Devices (latest edition), and the "Work Area Traffic Control Handbook" (WATCH) (latest edition).
The work shall include furnishing all labor, materials, equipment, and other incidentals including but not limited to: preparation of a traffic/work stage plan, obtaining City approval, and providing traffic control and pedestrian safety while maintaining through traffic and property access during the whole duration of construction.
The work staging plan shall consist of the proposed order of Contract work and subsequent impact to adjacent properties, pedestrians, and through traffic. The City has to approve the “Work Staging” of the project before the Contractor starts the preparation of the Traffic Control Plan.
This item of work shall also include delivering all required public notifications and temporary parking permits, posting signs, preparing traffic control plans prepared and signed by a California licensed traffic engineer, providing the traffic control and pedestrian safety required by the project including, but not limited to, signs, cones, barricades, warning tape, flashing arrow signs, K-rail, steel plates, temporary striping, paving, and/or lighting, and flag persons.
Full compensation for conforming to the requirements for TRAFFIC CONTROL AND PEDESTRIAN SAFETY shall be made at the Contract Unit Price per Lump Sum (LS) and shall include furnishing all labor, materials, tools, equipment and incidentals required to complete the work. No additional compensation shall be allowed therefore.
Progress payments shall be pro-rated in proportion to the total value of work completed to date as a function of the total awarded contract amount.
3. Remove Existing and Construct New 4-Inch Thick PCC Sidewalk Remove existing and construct new 4-inch thick PCC Sidewalk as specified in the Plans and Specifications including Special Conditions Sections 02210, 03000, and 14104. The work shall include furnishing all labor, materials, tools, equipment, and other incidentals including but not limited to: sawcutting, breaking, removal of PCC and reinforcement, excavation, disposal, protection and/or replacement of all existing drains, subgrade preparation, root removal, forms for tree wells, under sidewalk drain improvements, utility adjustments, placement and curing of new PCC, restoring form areas and all other associated work as necessary to remove existing and construct new 4-inch thick PCC sidewalk in accordance with the Plans and Specifications.
Full compensation for conforming to the requirements of REMOVE EXISTING AND CONSTRUCT NEW 4-INCH THICK PCC SIDEWALK shall be made at the Contract Unit Price bid per SQUARE FOOT (SF) removed and installed and shall include all labor, materials, tools, equipment, and incidentals necessary to complete the work. No additional compensation will be allowed therefore.
4. Remove Existing and Construct New 4-Inch Thick PCC Driveway Remove existing and construct new 4-inch thick PCC Driveway as specified in the Plans and Specifications including Special Conditions Sections 02210, 03000, and 14104. The work shall include furnishing all labor, materials, tools, equipment, and other incidentals including but not limited to: sawcutting, breaking, removal of PCC and reinforcement, excavation, disposal, protection and/or replacement of all existing drains, subgrade preparation, root removal, forms, placement and curing of new PCC, restoring form areas, and all other associated work as necessary to remove existing and construct new 4-inch thick PCC Driveway in accordance with the Plans and Specifications.
Full compensation for conforming to the requirements of REMOVE EXISTING AND CONSTRUCT NEW 4-INCH THICK PCC DRIVEWAY shall be made at the Contract Unit Price bid per SQUARE FOOT (SF) removed and installed and shall include all labor, materials, tools, equipment and incidentals required to complete the work. No additional compensation will be allowed therefore.
5. Remove Existing and Construct New PCC Curb and Gutter Type A2-8(200) (W=1’)
6. Remove Existing and Construct New PCC Curb and Gutter Type A2-8(200) (W=2’) Remove existing and construct new PCC Curb and Gutter as described on (Items 6 and 7) as specified in the Plans and Specifications including Special Conditions Sections 02210, 03000, and 14104. The work shall include furnishing all labor, materials, tools, equipment, and other incidentals including but not limited to: sawcutting, breaking, removal of PCC and reinforcement, removal of adjacent AC pavement, excavation, disposal, protection and/or replacement of all existing drains, subgrade preparation, root removal, forms, placement and curing of new PCC, restoring form areas, AC paveout, parkway restoration and reseeding, irrigation and sprinkler system repair and/or relocation and all other associated work as necessary to remove existing and construct new PCC Curb and Gutter as described on (Items 6 and 7) in accordance with the Plans and Specifications.
Full compensation for conforming to the requirements of REMOVE EXISTING AND CONSTRUCT NEW PCC CURB AND GUTTER AS DESCRIBED ON (ITEMS 6 AND7) shall be made at the Contract Unit Price bid per LINEAR FOOT (LF) removed and installed and shall include all labor, materials, tools, equipment and incidentals required to complete the work. No additional compensation will be allowed therefore.
7. Construct New 8-Inch Thick Electrical Cabinet and Step Down Transformer PCC Pads Construct new 8-inch thick electrical cabinet and step down transformer PCC pads as specified in the Plans and Specifications including Special Conditions Sections 02210, 03000, and 14104 . The work shall include furnishing all labor, materials, tools, equipment, and other incidentals including but not limited to: excavation, disposal, protection and/or replacement of all existing drains, subgrade preparation, root removal, forms for tree wells, placement and curing of new PCC,
restoring form areas and all other associated work as necessary to construct new 8-inch thick electrical cabinet and step down transformer PCC pads in accordance with the Plans and Specifications.
Full compensation for conforming to the requirements of CONSTRUCT NEW 8-INCH THICK ELECTRICAL CABINET AND STEP DOWN TRANSFORMER PCC PADS shall be made at the Contract Unit Price bid per SQUARE FOOT (SF) installed in place and shall include all labor, materials, tools, equipment, and incidentals required to complete the work. No additional compensation will be allowed therefore.
8. Furnish and Install Removable Bollard
Furnish and install removable bollard as specified in the Plans and Specifications. The work shall include furnishing all labor, materials, tools, equipment, and other incidentals including but not limited to: excavation, disposal, subgrade preparation, and root removal, as necessary to furnish and install removable bollard.
Full compensation for conforming to the requirements to FURNISH AND INSTALL REMOVABLE BOLLARD, shall be made at the Contract Unit Price per Each (EA) installed and shall include all labor, materials, tools, equipment, and incidentals required to complete the work. No additional compensation shall be allowed therefore.
9. Furnish and Install Sod; Install New Irrigation System and Connect To Existing Furnish and install sod; Install new irrigation system and connect to existing as specified in the Plans and Specifications. The work shall include furnishing all labor, materials, tools, equipment, and other incidentals including but not limited to: trenching, disposal, furnishing and installation of minimum 1-inch diameter irrigation lines, irrigation heads to provide head-head coverage, all associated fittings, valves, valve boxes, and appurtenances; flushing and pressure testing; backfill, compaction, placement of 5-inches of topsoil, placement of new Marathon sod, and 60-day plant establishment and maintenance period, as necessary to install new sod; install new irrigation system and connect to existing.
Full compensation for conforming to the requirements to FURNISH AND INSTALL SOD; INSTALL NEW IRRIGATION SYSTEM AND CONNECT TO EXISTING shall be made at the Contract Unit Price per Square Foot (SF) installed and shall include all labor, materials, tools, equipment, and incidentals required to complete the work. No additional compensation shall be allowed therefore.
SEWER LIFT STATIONS AND GRAVITY FORCE MAIN ABANDONMENTS
10. Remove Existing Below and Above Ground Blandwood Rd Lift Station Equipment, Plug Remaining Pipe, and Abandon Existing Lift Station Vault
11. Remove Existing Below and Above Ground True Ave Lift Station Equipment, Plug Remaining Pipe, and Abandon Existing Lift Station Vault Remove Existing Below and Above Ground Lift Station Equipment, Plug Remaining Pipe, and Abandon Existing Lift Station Vault as described on (Items 11 and 12) as specified in the Plans and Specifications including Special Conditions Sections 02050, 02210, and 14104. The work shall include furnishing all labor, materials, tools, equipment, and other incidentals including but not limited to: potholing; isolating, cutting, and dewatering existing mains; removal of existing below and above ground lift station equipment, and associated piping, valves, conduits, wires, light ing, cabinets, and meter poles; furnishing and installation of new caps/plugs; breaking and removing at minimum the top three feet of existing lift station vault; breaking and removing the bottom of the lift station vault; backfilling, compacting, restoration of AC and PCC; disposal, and other requirements of the Plans and Special Conditions as necessary to remove existing below and above ground lift station equipment, plug remaining pipe, and abandon existing lift station vault as described on (Items 11 and 12).
Full compensation for conforming to the requirements to REMOVE EXISTING BELOW AND
ABOVE GROUND LIFT STATION EQUIPMENT, PLUG REMAINING PIPE, AND ABANDON EXISTING LIFT STATION VAULT AS DESCRIBED ON (ITEMS 11 AND 12), shall be made at the Contract Unit Price bid per Lump Sum (LS) and shall include all labor, materials, tools, equipment,
and incidentals required to complete the work. No additional compensation shall be allowed therefore.
12. Plug Existing Pipes and Abandon Sewer Manhole (ID=4’)
13. Plug Existing Pipes and Abandon Sewer Manhole (ID=5’) Plug existing pipes and abandon sewer manhole as described on (Items 13 and 14) as specified in the Plans and Specifications including Special Conditions Sections 02050, 02210, and 14100 . The work shall include furnishing all labor, materials, tools, equipment, and other incidentals including but not limited to: potholing; isolating, cutting, and dewatering existing main; furnishing and installation of new caps/plugs; brick and mortar; breaking and removing at minimum the top three feet of existing manhole; breaking and removing the bottom of the manhole; backfilling, compacting, and restoration of AC; disposal, and other requirements of the Plans and Special Conditions as necessary to plug existing pipes and abandon sewer manhole as described on (Items 13 and 14).
Full compensation for conforming to the requirements to PLUG EXISTING PIPES AND ABANDON SEWER MANHOLE AS DESCRIBED ON (ITEMS 13 AND 14), shall be made at the Contract Unit Price bid per Each (EA) and shall include all labor, materials, tools, equipment, and incidentals required to complete the work. No additional compensation shall be allowed therefore.
GRAVITY SEWER MAIN, ASSOCIATED FITTINGS, AND IMPROVEMENTS
14. Furnish and Install 8-Inch Extra Strength VCP Sewer Main
15. Furnish and Install 6-Inch Extra Strength VCP Sewer Lateral Pipe Furnish and install extra strength VCP as described on (Items 15 and 16) as specified in the Plans and Specifications including Special Conditions Division 14. The work shall include furnishing all labor, materials, tools, equipment, and other incidentals including but not limited to: saw-cutting; potholing; excavation and permanent restoration of existing aggregate base and AC pavement to existing conditions plus 1-inch; clearing and grubbing; pipe installation; VCP fittings and couplings; vertical and horizontal offsets at points of connection to existing laterals and to avoid existing utilities; blanket protection per SPPWC Standard 225-2, supports for conduits across trenches per SPPWC Standard 224-2, trench sheeting; shoring; temporary AC resurfacing and plating; dewatering and flushing; leakage and infiltration testing; backfill; slurry; compaction; restoration of concrete curb, gutter, sidewalk, driveways, handicap ramps, miscellaneous landscaping, irrigation, and other requirements of the Plans and Special Conditions, and fittings not specifically included in separate bid items, and other incidentals and appurtenances necessary to furnish and install extra strength VCP as described on (Items 15 and 16).
Full compensation for conforming to the requirements to FURNISH AND INSTALL EXTRA STRENGTH VCP AS DESCRIBED ON (ITEMS 15 AND 16) shall be made at the Contract Unit Price bid per Linear Foot (LF) installed and shall include furnishing all labor, materials, tools, equipment, and incidentals required to complete the work. No additional compensation shall be allowed therefore.
16. Furnish and Install 8-Inch Class 200 DR14 Green PVC Sewer Force Main Pipe (Used For Gravity Application)
Furnish and install 8-inch Class 200 DR14 green PVC sewer force main pipe (used for gravity application) as specified in the Plans and Specifications including Special Conditions Division 14.
The work shall include furnishing all labor, materials, tools, equipment, and other incidentals including but not limited to: saw-cutting; potholing; excavation and permanent restoration of existing aggregate base and AC pavement to existing conditions plus 1-inch; clearing and grubbing; pipe installation; DIP fittings and couplings; blanket protection per SPPWC Standard 225-2, supports for conduits across trenches per SPPWC Standard 224-2, trench sheeting; shoring; temporary AC resurfacing and plating; dewatering and flushing; leakage and infiltration testing; backfill; slurry; compaction; restoration of concrete curb, gutter, sidewalk, driveways, handicap ramps, miscellaneous landscaping, irrigation, and other existing improvements disturbed; and other requirements of the Plans and Special Conditions, and fittings not specifically included in separate bid items, and other incidentals and appurtenances necessary to furnish and install 8-inch
Class 200 DR14 green PVC sewer force main pipe (used for gravity application).
Full compensation for conforming to the requirements to FURNISH AND INSTALL 8-INCH CLASS 200 DR14 GREEN PVC SEWER FORCE MAIN PIPE (USED FOR GRAVITY APPLICATION) shall be made at the Contract Unit Price per Lineal Foot (LF) installed and shall include furnishing, all labor, materials, equipment and incidentals required to complete the work. No additional compensation shall be allowed therefore.
17. Furnish and Install 8”X6” Extra Strength VCP Wye
Furnish and install 8”x6” extra strength VCP wye as specified in the Plans and Specifications including Special Conditions Division 14. The work shall include furnishing all labor, materials, tools, equipment, and other incidentals including but not limited to: saw-cutting; potholing; excavation and permanent restoration of existing aggregate base and AC pavement to existing conditions plus 1-inch; clearing and grubbing; VCP fittings and couplings; vertical and horizontal offsets at points of connection to existing laterals and to avoid existing utilities; blanket protection per SPPWC Standard 225-2, supports for conduits across trenches per SPPWC Standard 224-2, trench sheeting; shoring; temporary AC resurfacing and plating; dewatering and flushing; leakage and infiltration testing; backfill; slurry; compaction; restoration of concrete curb, gutter, sidewalk, driveways, handicap ramps, miscellaneous landscaping, irrigation, and other existing improvements disturbed; and other requirements of the Plans and Special Conditions, and fittings not specifically included in separate bid items, and other incidentals and appurtenances necessary to furnish and install 8”x6” extra strength VCP wye.
Full compensation for conforming to the requirements to FURNISH AND INSTALL 8”X6” EXTRA STRENGTH VCP WYE shall be made at the Contract Unit Price bid per Each (EA) installed and shall include furnishing all labor, materials, tools, equipment, and incidentals required to complete the work. No additional compensation shall be allowed therefore.
18. Remove Interfering Portions Of Existing Sewer Lateral; Abandon/Plug Remaining Portions Of Existing Sewer Lateral and Reconnect New Sewer Lateral To Existing With VCP Fittings and Materials
Remove interfering portions of existing sewer lateral; Abandon/plug remaining portions of existing sewer lateral and reconnect new sewer lateral to exiting with VCP fittings and materials as specified in the Plans and Specifications including Special Conditions Division 14. The work shall include furnishing all labor, materials, tools, equipment, and other incidentals including but not limited to: saw-cutting; potholing; isolating, cutting, and dewatering existing lateral; excavation and permanent restoration of existing aggregate base and AC pavement to existing conditions plus 1- inch; clearing and grubbing; installation of new VCP fittings and couplings; vertical and horizontal offsets at points of connection to existing laterals and to avoid existing utilities; blanket protection per SPPWC Standard 225-2, supports for conduits across trenches per SPPWC Standard 224-2, trench sheeting; shoring; temporary AC resurfacing and plating; backfill; slurry; compaction; restoration of concrete curb, gutter, sidewalk, driveways, handicap ramps, miscellaneous landscaping, irrigation, and other existing improvements disturbed; and other requirements of the Plans and Special Conditions as necessary to remove interfering portions of existing sewer lateral; abandon/plug remaining portions of existing sewer lateral and reconnect new sewer lateral to existing with VCP fittings and materials.
Full compensation for conforming to the requirements to REMOVE INTERFERING PORTIONS OF EXISTING SEWER LATERAL; ABANDON/PLUG REMAINING PORTIONS OF EXISTING SEWER
LATERAL AND RECONNECT NEW SEWER LATERAL TO EXISTING WITH VCP FITTINGS AND MATERIALS, shall be made at the Contract Unit Price bid per Each (EA) and shall include all labor, materials, tools, equipment, and incidentals required to complete the work. No additional compensation shall be allowed therefore.
19. Break Into Existing Brick Sewer Manhole and Re-Channelize Base Break into existing brick sewer manhole and re-channelize base as specified in the Plans and Specifications including Special Conditions Divisions 3 and 14. The work shall include furnishing all labor, materials, tools, equipment, and other incidentals including but not limited to: saw-cutting; potholing; isolating, cutting, plugging and/or providing temporary bypass on existing main;
excavation and permanent restoration of existing aggregate base and AC pavement to existing conditions plus 1-inch; clearing and grubbing; connecting new pipe to manhole; coring, breaking, and reconstructing base of manhole; blanket protection per SPPWC Standard 225-2, supports for conduits across trenches per SPPWC Standard 224-2, trench sheeting; shoring; temporary AC resurfacing and plating; backfill; slurry; compaction; and other requirements of the Plans and Special Conditions as necessary to break into existing brick sewer manhole and re-channelize base.
Full compensation for conforming to the requirements to BREAK INTO EXISTING BRICK SEWER MANHOLE AND RE-CHANNELIZE BASE, shall be made at the Contract Unit Price per Each (EA) sewer manhole broken into and shall include all labor, materials, tools, equipment, and incidentals required to complete the work. No additional compensation shall be allowed therefore.
FORCE SEWER MAIN, ASSOCIATED FITTINGS, AND IMPROVEMENTS
20. Furnish and Install 4-Inch Class 200 DR14 Green PVC Sewer Force Main Pipe Furnish and install 4-inch Class 200 DR14 Green sewer force main pipe as specified in the Plans and Specifications including Special Conditions Division 14. The work shall include furnishing all labor, materials, tools, equipment, and other incidentals including but not limited to: saw-cutting; potholing; excavation and permanent restoration of existing aggregate base and AC pavement to existing conditions plus 1-inch; clearing and grubbing; pipe installation; DIP fittings and couplings; vertical and horizontal offsets to avoid existing utilities; copper tracer wire and ID tape; blanket protection per SPPWC Standard 225-2, supports for conduits across trenches per SPPWC Standard 224-2, trench sheeting; shoring; temporary AC resurfacing and plating; dewatering and flushing; pressure testing; backfill; slurry; compaction; restoration of concrete curb, gutter, sidewalk, driveways, handicap ramps, miscellaneous landscaping, irrigation, and other existing improvements disturbed; and other requirements of the Plans and Special Conditions, and fittings not specifically included in separate bid items, and other incidentals and appurtenances necessary to furnish and install 4-inch Class 200 DR14 green PVC sewer force main pipe.
Full compensation for conforming to the requirements to FURNISH AND INSTALL 4-INCH CLASS 200 DR14 GREEN PVC SEWER FORCE MAIN PIPE shall be made at the Contract Unit Price per Lineal Foot (LF) installed and shall include furnishing, all labor, materials, tools, equipment and incidentals required to complete the work. No additional compensation shall be allowed therefore.
21. Furnish and Install 4-Inch Protecto-401 Lined Ductile Iron 45° MJ Wye and Thrust Block
22. Furnish and Install 4-Inch Protecto-401 Lined Ductile Iron 45° FL Wye and Thrust Block
23. Furnish and Install 4-Inch Protecto-401 Lined Ductile Iron 22.5° MJ Bend and Thrust Block
24. Furnish and Install 4-Inch Protecto-401 Lined Ductile Iron 45° MJ Bend and Thrust Block
25. Furnish and Install 4-Inch Protecto-401 Lined Ductile Iron 45° FL Bend and Thrust Block
26. Furnish and Install 4-Inch Protecto-401 Lined Ductile Iron MJxFL Adapter and Thrust Block
27. Furnish and Install 4-Inch Protecto-401 Lined Ductile Iron 90° MJ Elbow and Thrust Block
28. Furnish and Install 4-Inch Protecto-401 Lined Ductile Iron 90° FL Elbow Furnish and install Protecto-401 lined ductile iron fittings as described on (Items 22, 23, 24, 25, 26, 27, 28, and 29) as specified in the Plans and Specifications including Special Conditions Division
14. The work shall include furnishing all labor, materials, tools, equipment, and other incidentals including but not limited to: saw-cutting; potholing; excavation and permanent restoration of existing aggregate base and AC pavement to existing conditions plus 1-inch; clearing and grubbing; furnishing and installation of new fittings, thrust/anchor blocks; trench sheeting; shoring; temporary AC resurfacing and plating; flushing; pressure testing; backfill and compaction; and other requirements of the Plans and Special Conditions as necessary to furnish and install Protecto-401 lined ductile iron fittings as described on (Items 22, 23, 24, 25, 26, 27, 28, and 29).
Full compensation for conforming to the requirements to FURNISH AND INSTALL PROTECTO- 401 LINED DUCTILE IRON FITTINGS AS DESCRIBED ON (Items 22, 23, 24, 25, 26, 27, 28, and 29) shall be made at the Contract Unit Price bid per Each (EA) installed and shall include furnishing
all labor, materials, tools, equipment, and incidentals required to complete the work. No additional compensation shall be allowed therefore.
29. Furnish and Install 4-Inch Corrosion Resistant Cam and Groove Coupling and Dust Cap Furnish and install 4-inch corrosion resistant cam and groove coupling and dust cap as specified in the Plans and Specifications. The work shall include furnishing all labor, materials, tools, equipment, and other incidentals including but not limited to: saw-cutting; potholing; excavation and permanent restoration of existing aggregate base and AC pavement to existing conditions plus 1- inch; clearing and grubbing; furnishing and installation cam and groove coupling and dust cap; trench sheeting; shoring; temporary AC resurfacing and plating; flushing; pressure testing; backfill and compaction; and other requirements of the Plans and Special Conditions as necessary to furnish and install 4-inch corrosion resistant cam and groove coupling and dust cap.
Full compensation for conforming to the requirements to FURNISH AND INSTALL 4-INCH CORROSION RESISTANT CAM AND GROOVE COUPLING AND DUST CAP, shall be made a t the Contract Unit Price per Each (EA) installed and shall include all labor, materials, tools, equipment, and incidentals required to complete the work. No additional compensation shall be allowed therefore.
30. Break Into Existing Concrete Junction Structure and Connect New Sewer Force Main Break into existing concrete junction structure and connect new sewer force main as specified in the Plans and Specifications including Special Conditions Divisions 3 and 14. The work shall include furnishing all labor, materials, tools, equipment, and other incidentals including but not limited to: saw-cutting; potholing; isolating, cutting, and plugging/capping existing main; excavation and permanent restoration of existing aggregate base and AC pavement to existing conditions plus 1-inch; clearing and grubbing; connecting new force main to junction structure; coring, breaking, and reconstructing base of junction structure; blanket protection per SPPWC Standard 225-2, supports for conduits across trenches per SPPWC Standard 224-2, trench sheeting; shoring; temporary AC resurfacing and plating; backfill; slurry; compaction and other requirements of the Plans and Special Conditions as necessary to break into existing concrete junction structure and connect new sewer force main
Full compensation for conforming to the requirements to BREAK INTO EXISTING CONCRETE JUNCTION STRUCTURE AND CONNECT NEW SEWER FORCE MAIN, shall be made at the Contract Unit Price per Each (EA) shall include all labor, materials, tools, equipment, and incidentals required to complete the work. No additional compensation shall be allowed therefore.
SEWER VALVES
31. Furnish and Install 8-Inch MJ C509 Gate Valve and Anchor Block
32. Furnish and Install 4-Inch MJ C509 Gate Valve and Anchor Block
33. Furnish and Install 4-Inch FL C509 Gate Valve and Anchor Block
34. Furnish and Install 4-Inch Eccentric Plug Valve and Anchor Block
35. Furnish and Install 4-Inch Swing Check Valve and Anchor Block
36. Furnish and Install 4-Inch Flap Valve and Anchor Block Furnish and install valves as described on (Items 32, 33, 34, 35, 36, and 37) as specified in the Plans and Specifications including Special Conditions Division 14. The work shall include furnishing all labor, materials, tools, equipment, and other incidentals including but not limited to:
saw-cutting; potholing; excavation and permanent restoration of existing aggregate base and AC pavement to existing conditions plus 1-inch; clearing and grubbing; furnishing and installation of new valves, valve boxes and nut extensions (outside of vault/manhole areas), handwheels (where applicable) thrust/anchor blocks, concrete rings; flushing; pressure/leakage testing; backfill and compaction; and other requirements of the Plans and Special Conditions as necessary to furnish and install gate valves as described on (Items 32, 33, 34, 35, 36, and 37).
Full compensation for conforming to the requirements to FURNISH AND INSTALL GATE VALVES AS DESCRIBED ON (ITEMS 32, 33, 34, 35, 36, AND 37) shall be made at the Contract Unit Price
bid per Each (EA) installed and shall include furnishing all labor, materials, tools, equipment, and incidentals required to complete the work. No additional compensation shall be allowed therefore.
SEWER MANHOLES AND VAULTS
37. Furnish and Install 8-Ft (D=20-Ft) Reinforced Precast Concrete Sewer Lift Station Wet Well Manhole, With Coatings/Liner, Fillets, Pipe Connections and 4-Ft X 4-Ft Traffic Rated Access Hatch With Safety Chains, Net, and Associated Materials
38. Furnish and Install 8-Ft (D=13-Ft) Reinforced Precast Concrete Sewer Lift Station Overflow Manhole With Coatings/Liner, Fillets, Pipe Connections, and 3-Ft Diameter Traffic Rated Manhole Frame and Cover
Furnish and install reinforced precast concrete sewer lift station wet well and overflow manholes, with coatings/liners, fillets, pipe connections and hatch/cover as described on (Items 38 and 39 ) as specified in the Plans and Specifications including Special Conditions Divisions 3, 8, 9, and 14.
The work shall include furnishing all labor, materials, tools, equipment, and other incidentals including but not limited to: saw-cutting; potholing; excavation and permanent restoration of existing aggregate base and AC pavement to existing conditions plus 1-inch; clearing and grubbing; furnishing and installation of new lift station wet well and overflow manholes, coatings, liners, fillets, pipe and equipment connections and attachments; traffic rated hatches and frames/covers; safety chains/net; concrete rings; pressure/leakage testing; excavation sheeting; shoring; temporary AC resurfacing and plating; backfill and compaction; and other requirements of the Plans and Special Conditions as necessary to furnish and install reinforced precast concrete sewer lift station wet well manholes, with coatings/liner, fillets, pipe connections and hatch/cover as described on (Items 38 and 39).
Full compensation for conforming to the requirements to FURNISH AND INSTALL REINFORCED
PRECAST CONCRETE SEWER LIFT STATION WET WELL AND OVERFLOW MANHOLES,
WITH COATINGS/LINER, FILLETS, PIPE CONNECTIONS AND HATCH/COVER AS DESCRIBED ON (ITEMS 38 AND 39) shall be made at the Contract Unit Price bid per Each (EA) installed and shall include furnishing all labor, materials, tools, equipment, and incidentals required to complete the work. No additional compensation shall be allowed therefore.
39. Furnish and Install 6-Ft X 8-Ft (D=8-Ft) Precast Concrete Sewer Lift Station Valve Vault With Pipe Connections and 4-Ft X 6-Ft Traffic Rated Access Hatch With Safety Chains, Net, and Associated Materials
Furnish and install 6-Ft X 8-Ft (D=8-Ft) precast concrete sewer lift station valve vault with pipe connections and 4-Ft X 6-Ft traffic rated access hatch with safety chains, net, and associated materials as specified in the Plans and Specifications including Special Conditions Divisions 3, 8, and 14. The work shall include furnishing all labor, materials, tools, equipment, and other incidentals including but not limited to: saw-cutting; potholing; excavation and permanent restoration of existing aggregate base and AC pavement to existing conditions plus 1-inch; clearing and grubbing; furnishing and installation of new lift station valve vault, coatings, pipe and equipment connections and attachments; traffic rated hatches; safety chains/net; concrete rings ; pressure/leakage testing; excavation sheeting; shoring; temporary AC resurfacing and plating; backfill and compaction; and other requirements of the Plans and Special Conditions as necessary to furnish and install 6-Ft X 8-Ft (D=8-Ft) precast concrete sewer lift station valve vault with pipe connections and 4-Ft X 6-Ft traffic rated access hatch with safety chains, net, and associated materials.
Full compensation for conforming to the requirements to FURNISH AND INSTALL 6-FT X 8-FT (D=8-FT) PRECAST CONCRETE SEWER LIFT STATION VALVE VAULT WITH PIPE CONNECTIONS AND 4-FT X 6-FT TRAFFIC RATED ACCESS HATCH WITH SAFETY CHAINS, NET, AND ASSOCIATED MATERIALS shall be made at the Contract Unit Price bid per Each (EA) installed and shall include furnishing all labor, materials, tools, equipment, and incidentals required to complete the work. No additional compensation shall be allowed therefore.
40. Furnish and Install 4-Ft Diameter Precast Concrete Sewer Manhole With 2-Ft Traffic Rated Manhole Frame and Cover Per Std Plan 200-3
41. Furnish and Install 4-Ft Diameter Precast Concrete Drop Sewer Manhole With 2-Ft Traffic Rated Manhole Frame and Cover Per Std Plan 202-2
42. Furnish and Install 4-Ft Diameter Precast Concrete Force Main Cleanout Sewer Manhole With 2-Ft Traffic Rated Manhole Frame and Cover Per Std. Plan 200-3 Furnish and install 4-ft diameter precast concrete sewer manhole with 2-ft traffic rated manhole frame and cover as described on (Items 41, 42, and 43) as specified in the Plans and Specifications including Special Conditions Divisions 3 and 14. The work shall include furnishing all labor, materials, tools, equipment, and other incidentals including but not limited to: saw-cutting; potholing; excavation and permanent restoration of existing aggregate base and AC pavement to existing conditions plus 1-inch; clearing and grubbing; furnishing and installation of new sewer manholes, coating, pipe connections; channelizing the base; traffic rated frames/covers; concrete rings; pressure/leakage testing; excavation sheeting; shoring; temporary AC resurfacing and plating; backfill and compaction; and other requirements of the Plans and Special Conditions as necessary to furnish and install 4-ft diameter precast concrete sewer manhole with 2-ft traffic rated manhole frame and cover as described on (Items 41, 42, and 43).
Full compensation for conforming to the requirements to FURNISH AND INSTALL 4-FT DIAMETER PRECAST CONCRETE SEWER MANHOLE WITH 2-FT TRAFFIC RATED MANHOLE FRAME AND COVER AS DESCRIBED ON (ITEMS 41, 42, AND 43) shall be made at the Contract Unit Price bid per Each (EA) installed and shall include furnishing all labor, materials, tools, equipment, and incidentals required to complete the work. No additional compensation shall be allowed therefore.
43. Remove and Replace 2-Piece (26-Inch X 26-Inch) Sewer Force Main Junction Structure Frame and Lid With New 2-Piece Traffic Rated Steel Frame and Lid Remove and replace 2-piece (26-Inch X 26-Inch) sewer force main junction structure lid with new 2-piece traffic rated steel frame and lid as specified in the Plans and Specifications. The work shall include furnishing all labor, materials, tools, equipment, and other incidentals including but not limited to: removing and replacing 2-piece junction structure frame and lid with 2-piece traffic rated steel frame and lid; anchorage and hardware; cement mortar work; and other requirements of the Plans and Special Conditions as necessary to Remove and replace 2-piece (26-Inch X 26-Inch) sewer force main junction structure lid with new 2-piece traffic rated steel frame and lid.
Full compensation for conforming to the requirements to REMOVE AND REPLACE 2-PIECE (26- INCH X 26-INCH) SEWER FORCE MAIN JUNCTION STRUCTURE LID WITH NEW 2-PIECE TRAFFIC RATED STEEL FRAME AND LID shall be made at the Contract Unit Price bid per Each (EA) installed and shall include furnishing all labor, materials, tools, equipment, and incidentals required to complete the work. No additional compensation shall be allowed therefore.
SEWER LIFT STATION AND VALVE VAULT IMPROVEMENTS AND ACCESSORIES
44. Furnish and Install 175 Gpm Submersible Sewer Lift Station Pump With 7.5 Hp Explosion Proof Motor With Guide Rails, Pipe Supports, Brackets, and All Associated Materials Necessary For Installation
Furnish and install 175 gpm submersible sewer lift station pump with 7.5 hp explosion proof motor with guide rails, pipe supports, brackets, and all associated materials necessary for installation as specified in the Plans and Specifications including Special Conditions Division 11. The work shall include furnishing all labor, materials, tools, equipment, and other incidentals including but not limited to: furnishing and installation of new lift station pump and explosion proof motor; guide rail system; pipe and electrical connections, fittings, and attachments; operations integration; testing, troubleshooting, and startup; City training and maintenance documentation; and other requirements of the Plans and Special Conditions as necessary to furnish and install 175 gpm submersible sewer lift station pump with 7.5 hp explosion proof motor with guide rails, pipe supports, brackets, and all associated materials necessary for installation.
Full compensation for conforming to the requirements to FURNISH AND INSTALL 175 GPM SUBMERSIBLE SEWER LIFT STATION PUMP WITH 7.5 HP EXPLOSION PROOF MOTOR
WITH GUIDE RAILS, PIPE SUPPORTS, BRACKETS, AND ALL ASSOCIATED MATERIALS
NECESSARY FOR INSTALLATION shall be made at the Contract Unit Price bid per Each (EA) installed and shall include furnishing all labor, materials, tools, equipment, and incidentals required to complete the work. No additional compensation shall be allowed therefore.
45. Furnish and Install Automatic Sewer Lift Station Wet Well Washing System With Extendable Arm, Guide Rails, Brackets, Solenoid, and All Associated Materials Necessary For Installation
Furnish and install automatic sewer lift station wet well washing system with extendable arm, guide rails, brackets, solenoid, and all associated materials necessary for installation as specified in the Plans and Specifications including Special Conditions Divisions 11 and 16. The work shall include furnishing all labor, materials, tools, equipment, and other incidentals including but not limited to:
furnishing and installation of new lift station wet well washing system with extendable arm; guide rail system; pipe and electrical connections, fittings, and attachments; brackets and hardware; solenoid; operations integration; testing, troubleshooting, and startup; City training and maintenance documentation; and other requirements of the Plans and Special Conditions as necessary to furnish and install automatic sewer lift station wet well washing system with extendable arm, guide rails, brackets, solenoid, and all associated materials necessary for installation.
Full compensation for conforming to the requirements to FURNISH AND INSTALL AUTOMATIC
SEWER LIFT STATION WET WELL WASHING SYSTEM WITH EXTENDABLE ARM, GUIDE
RAILS, BRACKETS, SOLENOID, AND ALL ASSOCIATED MATERIALS NECESSARY FOR INSTALLATION shall be made at the Contract Unit Price bid per Each (EA) installed and shall include furnishing all labor, materials, tools, equipment, and incidentals required to complete the work. No additional compensation shall be allowed therefore.
46. Furnish and Install 2-Inch Water Service, 1-1/2-Inch Meter and Box Furnish and install 2-inch water service, 1-1/2-inch meter and box as specified in the Plans and Specifications including Special Conditions Division 14. The work shall include furnishing all labor, materials, tools, equipment, and other incidentals including but not limited to: trenching; boring; furnishing and installation of line taps, saddles, corporation stops, copper service lines, all associated fittings, curb/angle stops, meters, boxes/vaults, radio read devices, and appurtenances; procurement of tapping contractor; trench resurfacing; thrust/anchor blocks; flushing; disinfection; pressure and bacteriological testing; backfill and compaction; and other requirements of the Plans and Special Conditions as necessary to furnish and install 2-inch water service, 1-1/2-inch meter and box.
Full compensation for conforming to the requirements to FURNISH AND INSTALL 2-INCH WATER SERVICE, 1-1/2-INCH METER AND BOX, shall be made at the Contract Unit Price bid per Each (EA) installed and shall include furnishing all labor, materials, tools, equipment, and incidentals necessary for doing the work. No additional compensation will be allowed therefore.
47. Furnish and Install 1-1/2-Inch Reduced Pressure Principle (RP) Device Furnish and install 1-1/2-inch reduced pressure principle (RP) device as specified in the Plans and Specifications including Special Conditions Division 14. The work shall include furnishing all labor, materials, tools, equipment, and other incidentals including but not limited to: trenching and excavation; furnishing and installation of reduced pressure principle device complete with all associated copper and brass fittings and appurtenances; certified backflow testing of RP device before activating; thrust/anchor blocks; flushing; disinfection; pressure and bacteriological testing; backfill and compaction; restoration of landscaping and irrigation disturbed; and other requirements of the Plans and Special Conditions as necessary to furnish and install 1-1/2-inch reduced pressure principle (RP) device.
Full compensation for conforming to the requirements to FURNISH AND INSTALL 1-1/2-INCH REDUCED PRESSURE PRINCIPLE (RP) DEVICE, shall be made at the Contract Unit Price bid per Each (EA) installed and shall include furnishing all labor, materials, tools, equipment, and incidentals necessary for doing the work. No additional compensation will be allowed therefore.
48. Furnish and Install 10”W X 22”L X 24”H RP Enclosure With Concrete Pad Furnish and install 10”W X 22”L X 24”H RP enclosure with concrete pad as specified in the Plans and Specifications including Special Conditions Division 14. The work shall include furnishing all labor, materials, tools, equipment, and other incidentals including but not limited to: trenching and excavation; subgrade preparation; furnishing and installation of RP enclosure complete with all associated hardware and appurtenances; PCC pad; restoration of landscaping and irrigation disturbed; and other requirements of the Plans and Special Conditions as necessary to and install 10”W X 22”L X 24”H RP enclosure with concrete pad.
Full compensation for conforming to the requirements to FURNISH AND INSTALL 10”W X 22”L X 24”H RP ENCLOSURE WITH CONCRETE PAD, shall be made at the Contract Unit Price bid per Each (EA) installed and shall include furnishing all labor, materials, tools, equipment, and incidentals necessary for doing the work. No additional compensation will be allowed therefore.
49. Furnish and Install Ultrasonic Level Transducer With All Associated Brackets and Materials Necessary For Installation
Furnish and install ultrasonic level transducer with all associated brackets and materials necessary for installation as specified in the Plans and Specifications. The work shall include furnishing all labor, materials, tools, equipment, and other incidentals including but not limited to: furnishing and installation of new ultrasonic level transducer system; pipe and electrical connections, fittings, and attachments; brackets and hardware; operations integration; testing, troubleshooting and startup; City training and maintenance documentation; and other requirements of the Plans and Special Conditions as necessary to furnish and install ultrasonic level transducer with all associated brackets and materials necessary for installation.
Full compensation for conforming to the requirements to FURNISH AND INSTALL ULTRASONIC
LEVEL TRANSDUCER WITH ALL ASSOCIATED BRACKETS AND MATERIALS NECESSARY FOR INSTALLATION shall be made at the Contract Unit Price bid per Each (EA) installed and shall include furnishing all labor, materials, tools, equipment, and incidentals required to complete the work. No additional compensation shall be allowed therefore.
50. Furnish and Install Float Switch Level Control Assembly With All Associated Brackets and Materials Necessary For Installation
Furnish and install float switch level control assembly with all associated brackets and materials necessary for installation as specified in the Plans and Specifications. The work shall include furnishing all labor, materials, tools, equipment, and other incidentals including but not limited to:
furnishing and installation of new float switch level control system; pipe and electrical connections, fittings, and attachments; brackets and hardware; operations integration; testing, troubleshooting and startup; City training and maintenance documentation; and other requirements of the Plans and Special Conditions as necessary to furnish and install float switch level control assembly with all associated brackets and materials necessary for installation.
Full compensation for conforming to the requirements to FURNISH AND INSTALL FLOAT
SWITCH LEVEL CONTROL ASSEMBLY WITH ALL ASSOCIATED BRACKETS AND MATERIALS NECESSARY FOR INSTALLATION shall be made at the Contract Unit Price bid per Each (EA) installed and shall include furnishing all labor, materials, tools, equipment, and incidentals required to complete the work. No additional compensation shall be allowed therefore.
51. Furnish and Install Sewer Lift Station Valve Vault Access Ladder, All Associated Brackets, and Materials Necessary For Installation
Furnish and install sewer lift station valve vault access ladder, all associated brackets, and materials necessary for installation as specified in the Plans and Specifications including Special Conditions Division 11. The work shall include furnishing all labor, materials, tools, equipment, and other incidentals including but not limited to: furnishing and installation of new valve vault access ladder; safety system; brackets and hardware; and other requirements of the Plans and Special Conditions as necessary to furnish and install sewer lift station valve vault access ladder, all associated brackets, and materials necessary for installation.
Full compensation for conforming to the requirements to FURNISH AND INSTALL SEWER LIFT
STATION VALVE VAULT ACCESS LADDER, ALL ASSOCIATED BRACKETS, AND MATERIALS NECESSARY FOR INSTALLATION shall be made at the Contract Unit Price bid per Each (EA) installed and shall include furnishing all labor, materials, tools, equipment, and incidentals required to complete the work. No additional compensation shall be allowed therefore.
52. Furnish and Install 4-Inch Diameter Sewer Lift Station Valve Vault Floor Drain, P-Trap, and Associated Materials
Furnish and install 4-inch diameter sewer lift station valve vault floor drain, P-trap, and associated materials as specified in the Plans and Specifications. The work shall include furnishing all labor, materials, tools, equipment, and other incidentals including but not limited to: trenching and excavation; coring; furnishing and installation of valve vault floor drain complete with all associated pipe fittings, P-trap, and appurtenances; backfill and compaction; cement mortar; sealants and caulking; and other requirements of the Plans and Special Conditions as necessary to furnish and install 4-inch diameter sewer lift station valve vault floor drain, P-trap, and associated materials.
Full compensation for conforming to the requirements to FURNISH AND INSTALL 4-INCH
DIAMETER SEWER LIFT STATION VALVE VAULT FLOOR DRAIN, P-TRAP, AND ASSOCIATED MATERIALS, shall be made at the Contract Unit Price bid per Each (EA) installed and shall include furnishing all labor, materials, tools, equipment, and incidentals necessary for doing the work. No additional compensation will be allowed therefore.
53. Furnish and Install 4-Inch Diameter Schedule 80 PVC Sewer Lift Station Valve Vault Floor Drain Pipe
Furnish and install 4-inch diameter schedule 80 PVC sewer lift station valve vault floor drain pipe as specified in the Plans and Specifications including Special Conditions Divisions 11 and 14. The work shall include furnishing all labor, materials, tools, equipment, and other incidentals including but not limited to: saw-cutting; potholing; excavation and permanent restoration of existing aggregate base and AC pavement to existing conditions plus 1-inch; clearing and grubbing; pipe installation; fittings and couplings; horizontal offsets to avoid existing utilities; copper tracer wire and ID tape; blanket protection per SPPWC Standard 225-2, supports for conduits across trenches per SPPWC Standard 224-2, trench sheeting; shoring; temporary AC resurfacing and plating; dewatering and flushing; pressure testing; backfill; slurry; compaction; and other requirements of the Plans and Special Conditions, and other incidentals and appurtenances necessary to furnish and install 4-inch diameter schedule 80 PVC sewer lift station valve vault floor drain pipe.
Full compensation for conforming to the requirements to FURNISH AND INSTALL 4-INCH DIAMETER SCHEDULE 80 PVC SEWER LIFT STATION VALVE VAULT FLOOR DRAIN PIPE shall be made at the Contract Unit Price per Lineal Foot (LF) installed and shall include furnishing, all labor, materials, tools, equipment and incidentals required to complete the work. No additional compensation shall be allowed therefore.
54. Furnish and Install Adjustable Sewer Lift Station Valve Vault Pipe Supports and Associated Anchors Necessary For Installation
Furnish and install adjustable sewer lift station valve vault pipe supports and associated anchors necessary for installation as specified in the Plans and Specifications including Special Conditions Division 11. The work shall include furnishing all labor, materials, tools, equipment, and other incidentals including but not limited to: furnishing and installation of new adjustable valve vault pipe supports; anchors, brackets, and hardware; coatings; and other requirements of the Plans and Special Conditions as necessary to furnish and install adjustable sewer lift station valve vault pipe supports and associated anchors necessary for installation.
Full compensation for conforming to the requirements to FURNISH AND INSTALL ADJUSTABLE
SEWER LIFT STATION VALVE VAULT PIPE SUPPORTS AND ASSOCIATED ANCHORS NECESSARY FOR INSTALLATION shall be made at the Contract Unit Price bid per Each (EA) installed and shall include furnishing all labor, materials, tools, equipment, and incidentals required to complete the work. No additional compensation shall be allowed therefore.
55. Furnish and Install 6-Inch Diameter Schedule 80 PVC Sewer Lift Station Valve Vault Air Vent Assembly Including All Associated Piping, Fittings, Brackets/Supports, and Connections Necessary For Installation
Furnish and install 6-inch diameter schedule 80 PVC sewer lift station valve vault air vent assembly including all associated piping, fittings, brackets/supports, and connections necessary for installation as specified in the Plans and Specifications including Special Conditions Divisions 11 and 14. The work shall include furnishing all labor, materials, tools, equipment, and other incidentals including but not limited to: saw-cutting; potholing; excavation and permanent restoration of existing aggregate base and AC pavement to existing conditions plus 1-inch; clearing and grubbing; pipe installation; fittings and couplings; air vent piping; vertical and horizontal offsets to avoid existing utilities; copper tracer wire and ID tape; blanket protection per SPPWC Standard 225-2, supports for conduits across trenches per SPPWC Standard 224-2, trench sheeting; shoring; temporary AC resurfacing and plating; pressure testing; backfill; slurry; compaction; restoration of concrete curb, gutter, sidewalk, miscellaneous landscaping, irrigation, and other existing improvements disturbed; and other requirements of the Plans and Special Conditions, and other incidentals and appurtenances necessary to furnish and install 6-inch diameter schedule 80 PVC sewer lift station valve vault air vent assembly including all associated piping, fittings, brackets/supports, and connections necessary for installation.
Full compensation for conforming to the requirements to FURNISH AND INSTALL 6-INCH DIAMETER SCHEDULE 80 PVC SEWER LIFT STATION VALVE VAULT AIR VENT ASSEMBLY
INCLUDING ALL ASSOCIATED PIPING, FITTINGS, BRACKETS/SUPPORTS, AND CONNECTIONS NECESSARY FOR INSTALLATION shall be made at the Contract Unit Price per Lump Sum (LS) and shall include furnishing, all labor, materials, tools, equipment and incidentals required to complete the work. No additional compensation shall be allowed therefore.
56. Furnish and Install 4-Inch Flow Meter and All Associated Materials Necessary For Installation
Furnish and install automatic 4-inch flow meter and all associated materials necessary for installation as specified in the Plans and Specifications including Special Conditions Divisions 11, 14, and 16. The work shall include furnishing all labor, materials, tools, equipment, and other incidentals including but not limited to: furnishing and installation of new 4-inch flow meter; pipe and electrical connections, fittings, and attachments; brackets and hardware; operations integration; testing, troubleshooting, and startup; City training and maintenance documentation; and other requirements of the Plans and Special Conditions as necessary to furnish and install automatic 4-inch flow meter and all associated materials necessary for installation..
Full compensation for conforming to the requirements to FURNISH AND INSTALL AUTOMATIC 4-
INCH FLOW METER AND ALL ASSOCIATED MATERIALS NECESSARY FOR INSTALLATION shall be made at the Contract Unit Price bid per Each (EA) installed and shall include furnishing all labor, materials, tools, equipment, and incidentals required to complete the work. No additional compensation shall be allowed therefore.
57. Furnish and Install Sewer Lift Station Valve Vault and Electrical Cabinet Lighting Fixtures With All Associated Timer Switches and Brackets Necessary For Installation Furnish and install sewer lift station valve vault and electrical cabinet lighting fixtures with all associated timer switches and brackets necessary for installation as specified in the Plans and Specifications including Special Conditions Divisions 11 and 16. The work shall include furnishing all labor, materials, tools, equipment, and other incidentals including but not limited to: furnishing and installation of new lighting fixtures; conduit and electrical connections, fittings, and attachments; switches and other electrical components; brackets and hardware; operations integration; testing, troubleshooting, and startup; and other requirements of the Plans and Special Conditions as necessary to furnish and install sewer lift station valve vault and electrical cabinet lighting fixtures with all associated timer switches and brackets necessary for installation.
Full compensation for conforming to the requirements to FURNISH AND INSTALL SEWER LIFT
STATION VALVE VAULT AND ELECTRICAL CABINET LIGHTING FIXTURES WITH ALL ASSOCIATED TIMER SWITCHES AND BRACKETS NECESSARY FOR INSTALLATION shall be
made at the Contract Unit Price bid per Each (EA) installed and shall include furnishing all labor, materials, tools, equipment, and incidentals required to complete the work. No additional compensation shall be allowed therefore.
SEWER LIFT STATION ELECTRICAL IMPROVEMENTS
58. Furnish and Install 1-Inch PVC (Schedule 80) Conduit
59. Furnish and Install 1-1/2-Inch PVC (Schedule 80) Conduit
60. Furnish and Install 3-Inch PVC (Schedule 80) Conduit Furnish and install PVC (Schedule 80) conduit as described on (Items 59, 60, and 61) as specified in the Plans and Specifications including Special Conditions Divisions 14 and 16. The work shall include furnishing all labor, materials, tools, equipment, and other incidentals including but not limited to: saw-cutting; potholing; excavation and permanent restoration of existing aggregate base and AC pavement to existing conditions plus 1-inch; clearing and grubbing; boring; conduit installation; fittings, couplings, and pull rope; blanket protection per SPPWC Standard 225-2, supports for conduits across trenches per SPPWC Standard 224-2, trench sheeting; shoring; temporary AC resurfacing and plating; pressure testing; backfill; slurry; compaction; restoration of concrete curb, gutter, sidewalk, driveways, handicap ramps, miscellaneous landscaping, irrigation, and other existing improvements disturbed; and other requirements of the Plans and Special Conditions, and other incidentals and appurtenances necessary to furnish and install PVC (Schedule 80) conduit as described on (Items 59, 60, and 61).
Full compensation for conforming to the requirements to FURNISH AND INSTALL PVC (SCHEDULE 80) CONDUIT AS DESCRIBED ON (ITEMS 59, 60, AND 61) shall be made at the Contract Unit Price per Lineal Foot (LF) installed and shall include furnishing, all labor, materials, tools, equipment and incidentals required to complete the work. No additional compensation shall be allowed therefore.
61. Furnish and Install No. 6 Electrical Pull Box
Furnish and install No. 6 electrical pull box as specified in the Plans and Specifications including Special Conditions Divisions 14 and 16. The work shall include furnishing all labor, materials, tools, equipment, and other incidentals including but not limited to: excavation, gravel bed, pull box, adjustment to new grade, backfill and compaction and all other incidentals as needed to furnish and install No. 6 electrical pull box
Full compensation for conforming to the requirements to FURNISH AND INSTALL NO. 6 ELECTRICAL PULL BOX shall be made at the Contract Unit Price bid per Each (EA) installed and shall include furnishing all labor, materials, tools, equipment and incidentals required to complete the work. No additional compensation will be allowed therefore.
62. Furnish and Install No. 6 Conductors
63. Furnish and Install No. 8 Conductors
64. Furnish and Install No. 18 Conductors
65. Furnish and Install No. 10 Conductors
66. Furnish and Install No. 12 Conductors
Furnish and install conductors as described on (Items 63, 64, 65, 66, and 67) as specified in the Plans and Specifications including Special Conditions Division 16. The work shall include furnishing all labor, materials, tools, equipment, and other incidentals including but not limited to:
furnishing and installing specified size conductors; splicing; furnishing and installing all necessary line fuses, connections, connectors, and all other associated materials and other requirements of the Plans and Special Conditions, and other incidentals and appurtenances necessary to furnish and install conductors as described on (Items 63, 64, 65, 66, and 67).
Full compensation for conforming to the requirements of FURNISH AND INSTALL CONDUCTORS AS DESCRIBED ON (ITEMS 63, 64, 65, 66, AND 67) shall be made at the Contract Unit Price bid per Lineal Foot (LF) installed (measured horizontally) in place and shall include furnishing all labor,
materials, tools, equipment and incidentals required to complete the work. No additional compensation will be allowed therefore.
67. Remove Existing and Furnish and Install New 6’W X 4’D Double Door Electrical Cabinet Enclosure, All Associated Brackets, and Materials Necessary For Installation Remove existing and furnish and install new 6’W X 4’D double door electrical cabinet enclosure, all associated brackets, and materials necessary for installation as specified in the Plans and Specifications including Special Conditions Divisions 2, 11, and 16. The work shall include furnishing all labor, materials, tools, equipment, and other incidentals including but not limited to:
de-energizing, disconnecting, and removing existing electrical cabinet enclosure; excavation; coring; furnishing and installing new 6’W x 4’D double door electrical cabinet enclosure, all associated brackets, hardware, and materials necessary for installation; all connections and testing to assure completion of service cabinet; and other requirements of the Plans and Special Conditions, and other incidentals and appurtenances necessary to remove existing and furnish and install new 6’W X 4’D double door electrical cabinet enclosure, all associated brackets, and materials necessary for installation.
Full compensation for conforming to the requirements to REMOVE EXISTING AND FURNISH AND INSTALL NEW 6’W X 4’D DOUBLE DOOR ELECTRICAL CABINET ENCLOSURE, ALL ASSOCIATED BRACKETS, AND MATERIALS NECESSARY FOR INSTALLATION shall be made at the Contract Unit Price bid per Each (EA) and shall include all labor, materials, equipment and incidentals required to complete the work. All Southern California Edison fees shall be paid by the City. No additional compensation shall be allowed therefore.
68. Furnish and Install New Control Panel “CP”, All Associated Brackets, Accessories, Connections, and Fittings Necessary For Installation
69. Furnish and Install New Control Panel “A”, All Associated Brackets, Accessories, Connections, and Fittings Necessary For Installation
Furnish and install new control panel, all associated brackets, accessories, connections, and fittings necessary for installation as described on (Items 69 and 70) as specified in the Plans and Specifications including Special Conditions Divisions 2, 11, and 16. The work shall include furnishing all labor, materials, tools, equipment, and other incidentals including but not limited to:
furnishing and installing control panels, all associated brackets, hardware, and materials necessary for installation; all electrical components and wiring (breakers, contactors, fuses, switches, transformers, etc.); all connections; operations integration; testing, troubleshooting, and startup; and other requirements of the Plans and Special Conditions, and other incidentals and appurtenances necessary to furnish and install new control panel, all associated brackets, accessories, connections, and fittings necessary for installation as described on (Items 69 and 70).
Full compensation for conforming to the requirements to FURNISH AND INSTALL NEW
CONTROL PANEL, ALL ASSOCIATED BRACKETS, ACCESSORIES, CONNECTIONS, AND FITTINGS NECESSARY FOR INSTALLATION AS DESCRIBED ON (ITEMS 69 AND 70) shall be made at the Contract Unit Price bid per Each (EA) installed and shall include all labor, materials, equipment and incidentals required to complete the work. No additional compensation shall be allowed therefore.
70. Temporarily Relocate Existing Lift Station Electrical Cabinet/Enclosure and Reconnect Existing Power Supply Including All Conduit, Wires, Pull Boxes, and Other Materials As Necessary To Power Existing Lift Station While New Lift Station Is Being Built; Remove Upon Activation Of New Lift Station
Temporarily relocate existing lift station electrical cabinet/enclosure and reconnect existing power supply including all conduit, wires, pull boxes, and other materials as necessary to power Existing lift station while new lift station is being built; remove upon activation of new lift station as specified in the Plans and Specifications including Special Conditions Divisions 2, 11, and 16. The work shall include furnishing all labor, materials, tools, equipment, and other incidentals including but not limited to: de-energizing, disconnecting, and removing existing electrical cabinet enclosure; reconnecting existing power supply to existing lift station including all necessary conduits, wiring, pull boxes, connections, and associated materials necessary to power existing lift station until new
lift station is fully installed and functional and existing lift station is ready for demolition; use of portable generators; testing; eventual removal of existing power and existing cabinet; and other requirements of the Plans and Special Conditions, and other incidentals and appurtenances necessary to temporarily relocate existing lift station electrical cabinet/enclosure and reconnect existing power supply including all conduit, wires, pull boxes, and other materials as necessary to power Existing lift station while new lift station is being built; remove upon activation of new lift station.
Full compensation for conforming to the requirements to TEMPORARILY RELOCATE EXISTING
LIFT STATION ELECTRICAL CABINET/ENCLOSURE AND RECONNECT EXISTING POWER
SUPPLY INCLUDING ALL CONDUIT, WIRES, PULL BOXES, AND OTHER MATERIALS AS
NECESSARY TO POWER EXISTING LIFT STATION WHILE NEW LIFT STATION IS BEING BUILT; REMOVE UPON ACTIVATION OF NEW LIFT STATION shall be made at the Contract Unit Price bid per Lump Sum (LS) and shall include all labor, materials, equipment and incidentals required to complete the work. All Southern California Edison fees shall be paid by the City. No additional compensation shall be allowed therefore.
71. Remove Existing Lift Station Meter Pole and Pull Boxes/Vaults Remove existing lift station meter pole and pull boxes/vaults as specified in the Plans and Specifications including Special Conditions Divisions 2. The work shall include furnishing all labor, materials, tools, equipment, and other incidentals including but not limited to: coordinating with Southern California Edison for de-energizing and meter removal; disconnecting, excavating, and removing existing meter pole and associated conduit, wiring, pull boxes, and vaults; and other requirements of the Plans and Special Conditions, and other incidentals and appurtenances necessary to remove existing lift station meter pole and pull boxes/vaults.
Full compensation for conforming to the requirements to REMOVE EXISTING LIFT STATION METER POLE AND PULL BOXES/VAULTS shall be made at the Contract Unit Price bid per Each (EA) and shall include all labor, materials, tools, equipment and incidentals required to complete the work. All Southern California Edison fees shall be paid by the City. No additional compensation shall be allowed therefore.
72. Furnish and Install Hubble Lug Box At New Cabinet
Furnish and install hubble lug box at new cabinet as specified in the Plans and Specifications including Special Conditions Division 16. The work shall include furnishing all labor, materials, tools, equipment, and other incidentals including but not limited to: furnishing and installing hubble lug box, all associated brackets, hardware, and materials necessary for installation; all electrical components and wiring (breakers, contactors, fuses, switches, transformers, etc.); all connections; operations integration; testing, troubleshooting, and startup; and other requirements of the Plans and Special Conditions, and other incidentals and appurtenances necessary to furnish and install hubble lug box at new cabinet.
Full compensation for conforming to the requirements to FURNISH AND INSTALL HUBBLE LUG BOX AT NEW CABINET as specified in the Plans and Specifications shall be made at the Contract Unit Price bid per Each (EA) installed and shall include all labor, materials, tools, equipment and incidentals required to complete the work. No additional compensation shall be allowed therefore.
73. Furnish and Install Pump Starter
Furnish and install pump starter as specified in the Plans and Specifications including Special Conditions Divisions 11 and 16. The work shall include furnishing all labor, materials, tools, equipment, and other incidentals including but not limited to: furnishing and installation of new lift station pump starter; electrical connections, fittings, and attachments; operations integration; testing, troubleshooting, and startup; City training and maintenance documentation; and other requirements of the Plans and Special Conditions as necessary to furnish and install pump starter.
Full compensation for conforming to the requirements to FURNISH AND INSTALL PUMP STARTER shall be made at the Contract Unit Price bid per Each (EA) installed and shall include furnishing all labor, materials, tools, equipment, and incidentals required to complete the work. No additional compensation shall be allowed therefore.
74. Furnish and Install Manual Transfer Switch
Furnish and install manual transfer switch as specified in the Plans and Specifications including Special Conditions Division 16. The work shall include furnishing all labor, materials, tools, equipment, and other incidentals including but not limited to: furnishing and installing manual transfer switch, all associated brackets, hardware, and materials necessary for installation; all electrical components and wiring (breakers, contactors, fuses, switches, transformers, etc.); all connections; operations integration; testing, troubleshooting, and startup; and other requirements of the Plans and Special Conditions, and other incidentals and appurtenances necessary to furnish and install manual transfer switch.