City of Richmond: Temporary Sewage
Holding Tank Standards
City of Richmond
450 Civic Center Plaza
Richmond, CA 94804
Contact Watearth Principal
Jennifer J. Walker PE, DWRE, ENV SP, CFM, QSD, LEED AP BD+C 1151 Harbor Bay Parkway Suite 208H
Alameda, CA 94502
510.529.5552
[email protected]
March 13, 2026
Temporary Sewage Holding Tank
City of Richmond
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Table of Contents
Table of Contents ......................................................................................................................................... i Tables .......................................................................................................................................................... iii Figures ......................................................................................................................................................... iii Appendices ................................................................................................................................................ iii Acronyms and Abbreviations .................................................................................................................. iii Definition of Terms ...................................................................................................................................... iv
1.0 Introduction ........................................................................................................................................... 1
1.1 Authority and Adoption ................................................................................................................... 2
1.2 Performance Objectives .................................................................................................................. 3
2.0 Site and Setback Requirements .......................................................................................................... 3
2.1 General Requirements ..................................................................................................................... 3
2.2 Site and Setback for Below-ground Sewage Holding Tanks ........................................................ 4
2.2.1 Groundwater and Buoyancy Control ...................................................................................... 5
2.2.2 Soil Suitability ............................................................................................................................... 5
2.2.3 Soil Considerations...................................................................................................................... 6
2.2.4 Load Considerations .................................................................................................................. 6
2.2.5 Setback Adjustments ................................................................................................................. 6
2.3 Site and Setback for Above-ground Sewage Holding Tanks ...................................................... 6
2.3.1 Stability and Anchoring ............................................................................................................. 6
2.3.2 Secondary Containment ........................................................................................................... 6
2.3.3 Access and Maintenance ........................................................................................................ 7
2.3.4 Screening ..................................................................................................................................... 7
2.3.5 Setback Considerations ............................................................................................................. 7
2.3.6 Flood Zone Restrictions .............................................................................................................. 7
2.4 Site and Setback for Coastal Areas ................................................................................................ 8
3.0 Design Requirements............................................................................................................................ 8
3.1 Sewage Holding Tank Sizing ............................................................................................................ 8
3.2 Materials ............................................................................................................................................. 9
3.3 Alarms ............................................................................................................................................... 11
3.4 Plumbing and Piping ....................................................................................................................... 12
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3.5 Access .............................................................................................................................................. 14
3.6 Termination Fittings .......................................................................................................................... 14
3.7 Buoyancy ......................................................................................................................................... 14
4.0 Installation Procedures ....................................................................................................................... 15
4.1 Installation ........................................................................................................................................ 15
4.2 Inspection ......................................................................................................................................... 15
5.0 Operation and Maintenance Process .............................................................................................. 16
5.1 Odor Control .................................................................................................................................... 16
5.2 Good Workplace and Residential Practices ............................................................................... 16
5.3 Disposal Methods ............................................................................................................................ 17
6.0 Notification Requirements ................................................................................................................. 17
6.1 Pre-Installation Notification ............................................................................................................ 17
6.2 Operational Notification ................................................................................................................ 18
6.3 Emergency Notification.................................................................................................................. 18
6.4 System Modification or Abandonment ........................................................................................ 18
7.0 Abandonment Plan ............................................................................................................................ 18
7.1 Removal and Off-Site Disposal of Sewage Holding Tank and Contents................ .................. 19
7.2 On-Site Abandonment of Sewage Holding Tanks ...................................................................... 19
7.3 Abandonment Duration and Requirements ................................................................................ 19
8.0 Transition Plan for Ultimate Sewer Solution....................................................................................... 20
8.1 Applicability ..................................................................................................................................... 20
8.2 Notice of Sewer Availability ........................................................................................................... 20
8.3 Connection Requirements ............................................................................................................. 20
8.4 Abandonment and Site Restoration ............................................................................................. 20
8.5 Documentation and Verification .............................................................................................. 21
8.6 Failure to Transition ...................................................................................................................... 21
8.7 Special Circumstances ................................................................................................................... 21 References ................................................................................................................................................. 22
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Tables
Table 1: Minimum Setback to Sewage Holding Tanks ........................................................................... 4 Table 2: Materials Selection and Installation Scenarios ......................................................................... 9
Figures
Figure 1: Schematic Example of a Sewage Holding Tank System ........................................................ 1 Figure 2: Sewage Holding Tank ................................................................................................................. 2 Figure 3: An Example of a Fiberglass Sewage Holding Tank with an Anchoring System .................. 5 Figure 4: An Example of an Above-ground Sewage Holding Tank with a Second Containment .... 7 Figure 5: Sample Illustration of an Above-ground Polyethylene Sewage Holding Tank ................. 11 Figure 6: Sample Illustration of a Precast Sewage Holding Tank Located Below-ground ............... 11 Figure 7: Sample Illustration of an Alarm ............................................................................................... 12 Figure 8: Sample Illustration of an Alarm Setup .................................................................................... 12
Appendices
Appendix A – Keller Beach Sanitary Sewer (KBSS) Moratorium Area Appendix B – Safe Harbor Minimum Requirements
Appendix C – Basic Maintenance Checklist for Household Sewage Holding Tanks Appendix D – Spill Response and Reporting Guideline
Appendix E – Landslide Potential Map
Appendix F – Liquefaction Potential Map
Acronyms and Abbreviations
Acronym/Abbreviation Full Form
ACI American Concrete Institute
ASCE American Society of Civil Engineers
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Acronym/Abbreviation Full Form
ASSE American Society of Safety Engineers
ASTM American Society for Testing and Materials
BFE Base (100-year) Flood Elevation
CBC California Building Code
DEP Department of Environmental Protection
FEMA Federal Emergency Management Agency
ft feet
GRP Glass-fiber-reinforced Polyester
IAPMO International Association of Plumbing and Mechanical Officials IPC International Plumbing Code
IPSDC International Private Sewage Disposal Code
KBSS Keller Beach Sanitary Sewer
NOAA National Oceanic and Atmospheric Administration
PVC Polyvinyl Chloride
Definition of Terms
Abandon – To remove liquid waste from and either excavate or otherwise render inoperable a sewage holding tank.
Adjacent Cutback – A nearby steep slope that may impact site stability or water quality.
Building Line – A line running parallel to a lot line that is the required setback distance from the lot line as the closest portion of a building on the site. This setback may vary depending on the front, back and side of the building.
Buoyancy – The ability to float in water.
Buoyancy Related Movement – Buoyancy related movement is the opposite of settlement. Tanks or structures can float out of the ground when groundwater applies an upward buoyant force that causes the tank or structure to move upward. These conditions shall be co nsidered during the design process. This condition shall be considered during the design process.
Cast-in Place Concrete – Refers to concrete placed directly on a construction site using formwork instead of precast concrete.
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Certificate of Lateral Compliance – The certificate will be issued after a sewer lateral has been satisfactorily tested, without repair, or repaired and/or replaced.
City – City of Richmond, California.
Escarpment – A steep slope or long cliff formed by erosion or faulting, separating two relatively level or gently sloping surfaces.
Fill Bank – An artificially created slope or embankment formed by the placement of fill materia l, typically constructed to raise the elevation of the ground for roads, building sites, or infrastructure, and characterized by an abrupt or engineered slope face.
High Water Mark – The shore location reached by the sea at high tide, or by a lake or river at its highest water elevation.
HS-20 Loading – This is the term used by American Concrete Institute to describe normal movin g traffic loading conditions up to 18-wheeler loading.
Keller Beach Sanitary Sewer Moratorium – The Urgency Ordinance No. 01-22 imposed an immediate 45-day moratorium on the issuance of building permits for certain develo pment of activities requiring new connections to the KBSS in order for the City to evalu ate remediation options and development alternatives in lieu of connection to the KBSS.
Landward – Facing toward land as opposed to facing San Francisco Bay.
Lateral - The "Lateral”, “building sewer” , or “service lateral” is the sewer pipeline conveying wastewater from the premises of a user to the City’s sewer system.
Maintenance Hole – A structural opening at the top of each sewage holding tank compartment that allows access for cleaning, inspection, and maintenance activities. The ma intenance hole shall be sized to match the minimum riser diameter and serves as the connection point for the access riser and shall include sealing mechanisms to ensure a gastight and watertight seal.
Manifest System - Designed to track sewage waste from the time it leaves the generator facility or residence where it was produced until it reaches the off-site waste management facility tha t will store, treat, or dispose of it. It provides a detailed record of the items being transported, including their contents, destination, and handling instructions.
Moratorium – Delay in performing an obligation or taking an action legally authoriz ed or simply agreed to be temporary.
Natural Bluff – An undisturbed geological feature with a steep slope, typically adjacent to a water body or valley, formed through natural erosional processes.
Onsite Wastewater Treatment System – A sewage treatment and disposal system that includes a septic tank and disposal field, serves one or more structures on only one lot, and is projected to receive a sewage flow of 10,000 gallons or less per day.
Peak Daily Sewage Flow – The maximum volume of sewage that a sewage disposal system is projected to receive in a 24-hour period.
Pre-Cast Concrete – Cast offsite and then brought to a construction site to be assembled.
Qualified Professional – A civil engineer, environmental health specialist, geologist, professional soil scientist, or engineering geologist, who is licensed, registered or certified by the State o f California.
Riser – A riser is a vertical pipe or extension that connects the top of a sewage holding tank to the ground surface or access point, allowing for inspection, maintenance, or pumping.
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Sanitary Sewer – A wastewater collection system, owned and operated by a public agency with legal authority to collect wastewater from structures within the geographical a rea controlled by the public agency.
Secondary Containment – Secondary containment is a control measure, placed or built around a tank, to prevent its contents, such as leaks or spills, from leaving the area.
Septic Tank – A watertight receptacle designed and constructed to receive and partially treat sewage from buildings or structures.
Settlement – Occurs when a tank or structure lowers in elevation into the ground becau se the foundation was not adequately compacted to support the weight of the tank o r structure. The quality of compaction and the amount of settlement are determined by a geotechnical engineer based on evaluation of the types of soils present onsite and the soil compaction specified f or the tank or structure foundation. This condition shall be considered during the design process.
Professional Septic Tank Cleaner – A professional engaged in the business of cleaning septic tanks, sewage holding tanks, onsite wastewater treatment systems, privies, scenarios, or seepage pits.
Sewage – Liquid waste that contains or may be contaminated with human or animal e xcrement or offal.
Sewage Holding Tank – An alternative to a conventional onsite wastewater treatment system. It is a sewage collection system that includes a watertight tank designed to collect an d temporarily store sewage that is periodically removed by a permitted Professional Septic Tank Cleaner.
Sewage Sludge Hauler – A person who pumps or moves sewage sludge off-site by means of land- based vehicles, barges, ships, rails, pipelines, or other modes of transportation.
Termination Fitting – In sewage holding tank systems, termination fittings are the critical plumbing components located at the ends of vent, drain, and service lines that provide sealed, function al connections between the sewage holding tank and external piping systems.
Trap Arm – The horizontal section of the pipe between a plumbing fixture’s trap and the point where it connects to the main vent or drain.
Wastewater – Liquid waste, including but not limited to sewage.
Watertight – Tight construction or fit as to be impermeable to water.
Vent – A pipe or opening used for ensuring the circulation of air in a plumbing system and for reducing the pressure exerted on trap seals.
Temporary Sewage Holding Tank
City of Richmond
1 1.0 Introduction
The purpose of this document is to establish standards and procedures for the temporary use of sewage holding tanks in areas of the City of Richmond that are affected by sanitary sewer connection moratoriums. These standards are intended to address immediate infrastructure limitations, particularly in the Keller Beach Sanitary Sewer (KBSS) moratorium area, while enabling controlled development and safeguarding public health and environmental quality. The KBSS moratorium area is shown in Appendix A.
Although the initial application of these standards is focused on the KBSS area, the provisions outlined in this document are designed to be adaptable and enforceable in any future moratorium zones citywide. They are also applicable in areas not under the moratorium, bu t where implementation may still be necessary, such as for emergency backups.
Temporary sewage holding tanks serve as interim sewage containment systems where conventional sewer service is currently unavailable. These systems must be designed, installed, and maintained per the criteria outlined in this document to prevent public health hazards, groundwater contamination, nuisance conditions, and structural failures. A schematic exa mple of a sewage holding tank system is shown in Figure 1. A sewage holding tank example is shown in Figure 2.
This document provides comprehensive technical requirements for the setback, design, installation, operation, maintenance, and eventual decommissioning of temporary sewage holding tanks. This document also includes guidance on permitting, stakeholder responsibiliti es, and procedures for transitioning properties to permanent sewer infrastructure as it becomes available.
The sewage holding tank standards are to be applied in coordination with applicable loca l ordinances, state health and safety codes, and relevant engineering best practices. The City of Richmond will coordinate with Contra Costa County, as appropriate, to ensure consistency with County septic and onsite wastewater regulations; however, temporary sewage holding tanks governed by these Standards are reviewed and approved by the City under Municipal Code Chapter 12.19, “Onsite Wastewater Treatment Systems”.
Figure 1: Schematic Example of a Sewage Holding Tank System
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City of Richmond
2 Figure 2: Sewage Holding Tank
1.1 Authority and Adoption
These Temporary Sewage Holding Tank Standards are adopted by the City Council of the City of Richmond under Municipal Code Chapter 12.19, ‘Onsite Wastewater Treatment Systems’. These standards are performance-based and are intended to protect public health and the environment. They also provide a temporary wastewater management option where sanitary sewer service is unavailable due to a moratorium or other constraint.
The City of Richmond is the authority having jurisdiction for the review and approval of temporary sewage holding tank systems under these Standards. In exercising this authority, the City will apply the Contra Costa County Health Officer Regulations for Sewage Collection a nd Disposal (Contra Costa County Ord. Code § 420-6.606; Contra Costa County Health Officer Regulations for Sewage Collection and Disposal, 2018) and other applicable state requirements.
The City, not Contra Costa County, is the reviewing and permitting agency for temporary sewage holding tanks regulated under Chapter 12.19.
Compliance with these standards is determined by demonstrated achievement of performance outcomes, including protection of public health, prevention of environmental impacts, and reliable system operation. At a minimum, the system must operate without overflows, nuisance odors, or groundwater contamination. The system must also support a timely and verifiable transition to a permanent sanitary sewer connection when service becomes available.
Compliance is demonstrated through documented operation, maintenance, and inspections, including required pumping notices and manifest records for collection, transport, and disposal at an approved facility. Compliance is also demonstrated through submittals confirming sewer connection and holding tank abandonment within the required compliance period.
Temporary Sewage Holding Tank
City of Richmond
3 Prescriptive criteria in these Standards (including but not limited to setbacks, sizing formulas, material requirements, alarm provisions, and default pumping frequencies) are deemed-to- comply “Safe Harbor” provisions. Applicants may use these provisions without additional technical justification. Alternative designs may be approved where the applicant demonstrates equal or better performance to the satisfaction of the City.
This document includes several safe harbor provisions. These include the minimum requirements in Table 1, materials selection criteria in Table 2, sewage holding tank sizing formulas in Section
3.1, and pumping frequency provisions in Section 5.3. A sample Safe Harbor (Deemed-to- Comply) applicant checklist is included in Appendix B.
1.2 Performance Objectives
The objectives of these Standards are to:
1. Prevent discharge of sewage to the ground surface, storm drains, surface waters, or the City’s stormwater system.
2. Prevent contamination of groundwater, public drinking water wells, and other potable water supplies.
3. Avoid structural failure, settlement, or buoyancy-related movement of sewage holding tanks and associated appurtenances.
4. Prevent public health nuisances, including sewage backups into occupied structures and objectionable odors at property boundaries and public right-of-way.
5. Prevent standing sewage and unsanitary conditions onsite.
6. Provide overfill prevention through alarms and operational controls sufficient to give warning before the tank reaches full capacity.
7. Ensure that temporary sewage holding tanks can be safely and promptly decommissioned, and that structures are transitioned to permanent sewer service or other approved onsite wastewater treatment systems when available.
The City may approve alternative methods, materials, or designs when a qualified professional demonstrates, through calculations, manufacturer data, monitoring, or other evidence, that the proposed system will meet or exceed these performance objectives.
2.0 Site and Setback Requirements
The listed criteria are presumptively acceptable designs for site and setback compliance.
Alternatives may be approved by the City if the applicant demonstrates equal or better performance (e.g., through calculations, monitoring, or manufacturer data).
This section details the mandatory setback distances between sewage holding tanks and various site features. These requirements ensure that installations are properly positioned to protect public health, water resources, and infrastructure. Below-ground sewage holding tanks need proper groundwater clearance and suitable setbacks, especially in unstable soils. Above - ground sewage holding tanks require secure anchoring, secondary containment, and clear access. In flood or coastal zones, sewage holding tanks must be designed to withstand wave impact, erosion, and storm conditions. The site and setback requirements apply to all temporary sewage holding tank installations citywide, with immediate application in the KBSS moratoriu m area.
2.1 General Requirements
Minimum setback rules for sewage holding tank installations are detailed in Table 1 (Contra Costa County Ord. Code § 420-6.606; Contra Costa County Health Officer Regulati ons for
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City of Richmond
4 Sewage Collection and Disposal, 2018). Where compliance with minimum setbacks is not feasible due to site constraints, an alternative site and setback plan must be submitted by a registered professional engineer in California and approved by the City of Richmond unde r Chapter 12.19.040, in a manner consistent with Contra Costa County Health Officer Regulations for Sewage Collection and Disposal. If applicable, for properties with temporary sewage holding tanks that were legally installed prior to these regulations being adopted that may not be in full compliance, owners should still follow the minimum setback as closely as feasible.
Table 1: Minimum Setback to Sewage Holding Tanks
Site Feature Setback to
Sewage
Holding
Tanks (feet)
High water marks of bays, streams, rivers, canals 100
High water marks of ditches, culverts, ephemeral streams 50 High water marks of lakes, reservoirs 100
Depressions and low areas 5
Downslope or adjacent cutbanks, fill banks, escarpments, embankments, natural bluffs
10 Fill areas, unstable soil, unstable landforms, drainage swales 10 Trees 10
Structures, foundations 10
Underground irrigation or drainage systems (watertight piping) 10 Underground irrigation or drainage systems (non-watertight piping) 100 Easements 5
Public drinking water well 100
Pressurized water supply line 10
If the ground is rocky and fissures could take the outflow further, it should be greater than the nearest water supply siting
>50
2.2 Site and Setback for Below-ground Sewage
Holding Tanks
Below-ground sewage holding tanks must be sited and constructed in a manner that protects public health, water quality, and structural integrity. Below-ground sewage h olding tanks have
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5 different structural, geotechnical, and hydrology considerations. Installations shall comply with the following requirements:
2.2.1 Groundwater and Buoyancy Control
1. Sewage holding tanks must maintain a minimum vertical clearance of two feet above the seasonal high groundwater table unless engineered buoyancy countermeasures are provided (Contra Costa County Ord. Code § 420-6.606; Contra Costa County Health Officer Regulations for Sewage Collection and Disposal, 2018).
It is also important to follow all sewage holding tank manufacturer s’ recommendations related to buoyancy.
2. Where groundwater is present within five feet of the excavation bottom, sewage holding tanks shall be installed with anti-floatation slabs or other engineered anchoring systems to resist buoyant uplift. An example of an anchoring system is shown in Figure 3.
Figure 3: An Example of a Fiberglass Sewage Holding Tank with an Anchoring System
2.2.2 Soil Suitability
1. A geotechnical evaluation is required if the site contains expansive soils, unstable landforms, or is located in a designated landslide or liquefaction zone. In addition, a geotechnical evaluation may also be required by the Building Division for other conditions, as specified in California Building Code (CBC) 1803.5. As an additi onal document, the Landslide Potential Map is located in Appendix E, while the Liquefaction Potential Map is located in Appendix F.
2. Excavation and backfill must use materials and compaction methods per the sewage holding tank manufacturer’s specifications and geotechnical recommendations.
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City of Richmond
6 2.2.3 Soil Considerations
1. Design considerations should take into account the type of soil and subsoil. A minimum of 15 inches of soil cover must be placed on top of the sewage holding tank, but not sufficient alone under traffic loading. The top layer of the soil cover must be level with the natural grade.
2.2.4 Load Considerations
1. Below-ground sewage holding tanks located under driveways, parking areas, or other vehicular access points must be designed to withstand HS-20 loading or greater as required by site use.
2. Installations under structures or hardscape features are prohibited unless specifically engineered and approved by the City of Richmond, consistent with applicable Contra Costa County Health Officer regulations.
2.2.5 Setback Adjustments
1. The standard setbacks in Table 1 apply. However, where slope stability or groundwater conditions warrant, the City may increase setback requirements or require additional analysis.
2.3 Site and Setback for Above-ground Sewage
Holding Tanks
Above-ground sewage holding tanks present setback challenges related to visibility, access, containment, and safety. Above-ground sewage holding tanks shall comply with the followin g site and setback requirements:
2.3.1 Stability and Anchoring
1. All above-ground sewage holding tanks shall be anchored to resist lateral loads per CBC Chapter 16 and local lateral design speeds (minimum 100 mph 3-second gust, per ASCE 7).
2. Sewage holding tanks must be placed on a level, engineered pad or concrete slab capable of supporting the full tank weight, including liquid contents.
3. All above-ground sewage holding tanks must be supported by a level, engineered foundation.
2.3.2 Secondary Containment
1. Above-ground sewage holding tanks with a capacity of over 1,000 gallons must include secondary containment equal to at least 150% of the sewage holding tank volume (California Water Boards, California Code of Regulations, Title 23, Division 3, Chapter 16, 2020).
2. Containment areas must be lined, impermeable, and resistant to sewage degradation. While concrete may be used, it must be properly coated or sealed to achieve impermeability and chemical resistance. An example of an above-ground sewage holding tank containment is shown in Figure 4.
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City of Richmond
7 Figure 4: An Example of an Above-ground Sewage Holding Tank with a Second Co ntainment
2.3.3 Access and Maintenance
1. Sewage holding tanks shall be located with a minimum 10-foot clear zone for vehicle access (pump trucks) and unobstructed maintenance. Where feasible, a paved or otherwise stabilized path shall be provided to support all-weather service access.
2. A safe and stable working area shall always be maintained around the sewage holding tank.
2.3.4 Screening
1. Above-ground sewage holding tanks visible from public rights-of-way or residential properties must incorporate screening measures such as fencing, vegetation, or architectural enclosures consistent with City of Richmond’s Zoning and Subdivision Regulations (City of Richmond, Zoning and Subdivision Regulations, 2025) and neighborhood aesthetic guidelines.
2. In accordance with the Screening Regulations of the City of Richmond, all mechanical equipment, including sewage holding tanks if visible from public areas, must be screened from public view. If a sewage holding tank must be installed in the front yard, it will also be subject to these screening requirements to ensure it is not visible from public view.
3. An above-ground holding tank located facing a street must be screened to a height of 12 inches above the top of the tank, unless the required screening interferes with utility access, in which case reasonable accommodation must be provided.
2.3.5 Setback Considerations
1. Above-ground sewage holding tanks shall meet all applicable setbacks per Table 1 and shall not be placed within utility easements, public sidewalks, or within 5 feet of property lines unless specifically approved.
2.3.6 Flood Zone Restrictions
1. Above-ground sewage holding tank foundations in Federal Emergency Management Agency (FEMA)-designated flood zones must be elevated 18 inches above the base elevation (BFE) or otherwise protected by the City of Richmond Floodplain Management Ordinance.
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8 2.4 Site and Setback for Coastal Areas
In areas at risk of high-velocity flooding, wave impact, erosion, or storm-related damage, a sewage holding tank must incorporate specific design measures to ensure their protection and functionality:
1. Sewage holding tanks should be oriented to resist or minimize wave impacts and moving floodwaters.
2. The narrowest dimension of the sewage holding tank should be located perpendicular to the flood flow.
3. The sewage holding tank must be located landward of the building line when possible and landward of the easement at all times to ensure it will not release contaminants in a flood and can be used after flood waters recede.
4. The system must be designed and certified by a registered professional engineer in California to withstand damage during coastal storms.
5. The engineer shall submit calculations and drawings demonstrating that the temporary sewage holding tank meets applicable FEMA coastal zone construction criteria and local floodplain management regulations.
6. The setback requirements are intended to protect wells, surface water, and slope stability to prevent release of contaminants during flooding, wave impact, erosion, and coastal storms.
7. Alternative siting is acceptable where a qualified professional demonstrates equivalent protection (e.g., liners, structural supports, and additional containment).
Alternative setbacks may be approved if standard setbacks are not feasible, provided the design is prepared by a qualified engineer and approved by the City of Richmond, consistent with applicable Contra Costa County Health Officer regulations.
3.0 Design Requirements
The listed criteria are “presumptively acceptable designs” for design and construction compliance. Alternatives may be approved by the City if the applicant demonstrates equal or better performance (e.g., through calculations, monitoring, or manufacturer data). The Design Criteria Section outlines design and construction requirements, including minimum standards that must be met to obtain the construction permit. The Design Criteria Section covers critical aspects such as sewage holding tank sizing based on the intended application, appropriate material selection depending on installation conditions, and necessary features like alarms, plumbing, access points, and termination fittings to promote system efficiency and safety.
3.1 Sewage Holding Tank Sizing
The size of the sewage holding tank depends directly on the intended application, which includes single-family residences, multi-family homes, and other types of structures and la nd use.
Smaller sewage holding tanks require a more frequent pumping schedule. An oversized sewage holding tank that is pumped too infrequently can lead to odors arising from stagnant s ewage.
The required minimum size for sewage holding tanks varies according to the type of structure
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City of Richmond
9 and its associated land use (Contra Costa County Ord. Code § 420-6.606; Contra Costa County Health Officer Regulations for Sewage Collection and Disposal, 2018).
The sizing formulas below are intended as default minimums; however, an alternative volume may be considered where project-specific information demonstrates that the proposed design will still meet alarm/overflow performance targets.
1. Residential (Single-Family): For one or two bedrooms, the minimum capacity that will serve the dwelling is 1,000 gallons.
2. Residential (Three or More Bedrooms): For three or more bedrooms, the minimum capacity is 1,000 gallons for the first two bedrooms and 250 gallons for each additional bedroom.
3. Other Structures (Other than Single-Family Residential): The minimum capacity is calculated by multiplying the peak daily sewage flow of the structure by 0.75 and adding 1,125 gallons.
3.2 Materials
This subsection explains how to select appropriate sewage holding tank materials based on installation conditions and regulatory standards. Different installation scenarios (below -ground vs. above-ground) may require different material choices from among the approved options. The following requirements are mandatory and provide guidance for appropriate material selection:
1. The sewage holding tank must be watertight.
2. The sewage holding tank must be certified by the International Association of Plumbing and Mechanical Officials (IAPMO) as per Contra Costa County Ord. Code § 420-6.606; Contra Costa County Health Officer Regulations for Sewage Collection and Disposal, 2018.
3. If installed below-ground and exposed to traffic (e.g., under pavement or driveways), the sewage holding tank must be traffic-rated. The materials must withstand HS-20 load vehicles, as specified in Section 2.2.4 Load Considerations.
Table 2 summarizes approved sewage holding tank materials and material suitability for different installation scenarios, along with key limitations or considerations for each.
Table 2: Materials Selection and Installation Scenarios Material Below- or
Above-ground
Suitability
Advantages Limitations
Pre-cast Concrete Below-ground Typically pre-
manufactured in
controlled
environments, leading
to consistent quality
Typically assembled
on-site. Watertight
performance depends
on proper joint sealing
which can be a weak
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City of Richmond
10 Material Below- or
Above-ground
Suitability
Advantages Limitations
point if installation is
not done correctly
Cast-in-place Concrete Below-ground Offers robust load- bearing capacity
suitable for heavy
earth cover, and its
dimensions can be
tailored to site-specific
conditions
Susceptible to
chemical exposure if
not properly coated or
lined
Concrete Above-ground Suitable for large-
volume storage where
space permits
Concrete tanks require
a foundation designed
by a registered
professional engineer,
and need heavy
machinery for
installation, which
increases labor costs
Fiberglass Both Fiberglass is non-
reactive to sewage
byproducts
Because of the lighter
weight of the material,
it may float or shift,
which can be avoided
by properly anchoring
the tank to the ground
Polyethylene Both Less expensive than
concrete or fiberglass
alternatives
Performance may be
affected in high-
temperature
environments
Monolithic Concrete Both Can be engineered for
large capacities and
complex site conditions
Installation involves
significant site
preparation, formwork,
and curing time
Glass-fiber-reinforced
Polyester
Both Ideal for sewage
applications where
chemical exposure is a
concern
Glass-fiber-reinforced
Polyester (GRP) tanks
are not inherently
traffic-rated;
additional structural
reinforcement or
special installation
methods are needed
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City of Richmond
11 Examples of a polyethylene sewage holding tank and a precast sewage holding tank, respectively, are shown in Figures 5 and 6.
Figure 5: Sample Illustration of an Above-ground Polyethylene Sewage Holdi ng Tank
Figure 6: Sample Illustration of a Precast Sewage Holding Tank Located Be low-ground
3.3 Alarms
Properly functioning alarm systems are critical to the safe operation of temporary sewage holding tanks. The installed sewage holding tank must be equipped with a high-water sensing device and high-water audible and visual alarms. All alarm equipment must be located where it will not interfere with pumping, is not subject to mechanical damage, and is accessible for
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City of Richmond
12 repairs and adjustments. Alarms should be weatherproof or placed in a protective enclosure such as a covered area or box. An example of an alarm and setup is shown in Figures 7 and 8.
1. Alarm Location: The alarm system should be attached to the structure served, either on a pipe stand, or a wooden post within five feet of the structure (Contra Costa County Ord. Code § 420-6.606; Contra Costa County Health Officer Regulations for Sewage Collection and Disposal, 2018).
2. Alarm Settings: The alarm system installed in each sewage holding tank will need to indicate when the sewage holding tank is approximately 75% filled.
3. Electrical Consideration: The alarm system must be installed on a separate electrical circuit. Each installation must have an electrical disconnect within sight of the sewage holding tank.
Figure 7: Sample Illustration of an Alarm
Figure 8: Sample Illustration of an Alarm Setup
3.4 Plumbing and Piping
This section outlines plumbing and piping requirements for sewage holding tank systems, including water metering, backflow prevention, overflow control, approved pipe materials, watertight connections, and provisions for gravity flow and above-ground plumbing:
Temporary Sewage Holding Tank
City of Richmond
13 1. Water Meter: Any building or structure served by a sewage holding tank shall have a water meter, or meters, installed that measures all water that will be discharged as sewage from the building or structure.
2. Backflow Preventers: Backflow preventers should be installed on all sewage holding tanks to prevent backing up of sewage into the building and discharge of sewage into floodwater. Devices must be suitable for sewage conditions, including stainless steel models or those certified under ASSE 1013, or equivalent certifications designed for sewage use.
3. Overflow: Overflows must be above the base flood elevation.
4. Pipe Material: Use Schedule 40 PVC pipe and Schedule 40 PVC connection fittings for all transport lines (Contra Costa County Ord. Code § 420-6.606; Contra Costa County Health Officer Regulations for Sewage Collection and Disposal, 2018).
5. Plumbing Connections: Plumbing connections must be watertight.
6. Gravity Flow to Tank: Conventional plumbing requirements apply.
7. Pressure Flow to Tank: Pump activation and deactivation must be double controlled by float switches within the pump chamber and sewage holding tank. This is intended to prevent pumping excess sewage into the sewage holding tank. Exact elevations shall be determined based on tank geometry and manufacturer recommendations to ensure protection against overfill.
8. Above-ground Tank Plumbing: This configuration creates potential for physical damage to piping and tanks. Whenever piping is above-ground, it must be adequately protected from damage in accordance with the International Plumbing Code (IPC) § 305. Where multiple, interconnected tanks are installed, connections must be connected by differential settling using a common slab designed per ACI 318, flexible connections, or engineered bedding systems.
9. Future Connection to the City’s Sanitary Sewer: When the connection to the sanitary sewer becomes available, a disconnection valve and bypass piping must be pre- designed to enable transition without excavation of primary building sewer lines. The disconnection valve and bypass piping must be installed at the time the temporary sewage holding tank is installed. Pre-installation ensures a simple future connection transition process to the City's sanitary sewer (e.g. opening a valve). a. Disconnection valves must be installed downstream of the sewage holding tank outlet if gravity discharge is available (Onsite Wastewater Treatment System, California Code of Regulations, 2007). For pressurized or pumped systems, valves should be placed at a designated cleanout access point.
Additional guidelines on clean out requirements are provided in Section 708 of the IPC.
b. The plumbing layout must facilitate isolation of the sewage holding tank and rerouting of flow to the sewer. This can be achieved by installing a T-junction with a capped branch oriented toward the future sewer connection.
Additional guidelines on sanitary drainage and sewer are provided in Section 709 of the California Plumbing Code.
Temporary Sewage Holding Tank
City of Richmond
14 3.5 Access
Well-designed access points are essential for the system's long-term functionality and operational efficiency. For below-ground sewage holding tanks, it is important that the sewage holding tank is accessible at ground level. Accessibility is accomplished using a catch-b asin riser and access cover.
1. Access Points: Sewage holding tanks greater than 2,000 gallons must have multiple access points. Service access or pumping access ports must allow for efficient pumping of all contents.
2. Access Riser: A waterproof access riser with a gas-tight lid and seal must extend from the maintenance hole of each sewage holding tank compartment to the finished grade. The riser must be constructed of polyethylene, have a minimum diameter of 24 inches, and be of a size sufficient for the sewage holding tank maintenance hole.
Access risers must be traffic rated in areas that are surfaced by concrete, asphalt, or similar paving, or subject to vehicular traffic.
3.6 Termination Fittings
This subsection covers the connections and fittings necessary for system operation, highlighting the importance of proper ventilation, drainage, and provisions for future sewer connection.
Termination fittings are essential for proper system function. Well-designed plumbing elements prevent odor issues, support waste flow, and facilitate the eventual transition to permanent sewer service. Installers must ensure correct venting and drainage to maintain system integrity and performance.
1. The sewage holding tank shall be vented at the highest point (at the top) of the tank by one of the following methods: 1.25-inch minimum diameter individual vent pipe extending undiminished in size through the roof.
2. A wet vent may also serve as a drain line, as long as the section acting as the drain is one pipe size larger than the trap arm it serves.
3. Liquid waste holding tank drain opening shall be a minimum 1.50-inch pipe size.
4. Steel piping is not recommended due to the susceptibility to corrosion.
3.7 Buoyancy
Effective buoyancy control is crucial in the Richmond coastal environment and varies based on whether the system is below or above-ground:
1. Below-ground: The sewage holding tank must be inherently non-buoyant. A sewage holding tank is non-buoyant if installed above the groundwater elevation, weight of the empty tank exceeds buoyant forces, or “side wings” anchor the tank into surrounding soil. The sewage holding tank must be able to withstand traffic loading if the area is subject to vehicular traffic loads. One criterion would be to have a minimum of 15 inches of soil cover over the sewage holding tank to enhance stability and protection.
Temporary Sewage Holding Tank
City of Richmond
15 2. Above-ground: Must be designed and constructed to function as needed and retain shape, integrity, and watertightness. The buoyancy component must provide adequate support for all associated piping.
4.0 Installation Procedures
This section provides guidelines and regulatory considerations for the installation and inspection of sewage holding tanks. This section is intended to guide stakeholders —such as contractors, inspectors, and site planners—through the correct procedures for installations. The section emphasizes proper sewage holding tank placement, testing for watertight integrity, and compliance with the City of Richmond’s inspection protocols, consistent with applicable Contra Costa County Health Officer regulations, to ensure safe and effective sewage management systems.
4.1 Installation
Sewage holding tanks must meet approved standards and be securely installed in a location to be removable for service, repair, or replacement without the necessity of removing permanent, structural, mechanical, or electrical equipment (Contra Costa County Ord. Code § 420-6.606; Contra Costa County Health Officer Regulations for Sewage Collection and Disposal, 2018).
Sewage holding tank installations will not be approved if the site is suitable for another type of private sewage disposal system. Installation will follow once the City of Richmond approves the construction permit, consistent with applicable Contra Costa County Health Offic er regulations.
Additional details regarding the permitting process will be provided in the permit section.
1. Firm Bedding (above-ground): A sewage holding tank must be installed level on a firm bedding of compacted soil, sand, or gravel in accordance with the manufacturer’s specifications. Where sewage holding tanks are to be located on sloped terrain (greater than 5%), areas of fill, or near drainage paths, bedding must be designed by a qualified professional.
2. Pipes: All pipes that pass through a sewage holding tank must be sealed with a watertight sealant. In accordance with ASTM C923, examples of acceptable sealing methods include flexible rubber boots (commonly used for maintenance hole), or compression gaskets (commonly used to connect reinforced concrete maintenance hole or pipes) designed to maintain a seal under hydrostatic pressure.
3. Watertightness: Temporary sewage holding tanks must be demonstrated to be watertight by field testing conducted during installation in the presence of the City of Richmond representative.
4. Testing Procedure: Fill sewage holding tanks with water 2 inches into riser connections at least 24 hours prior to commencement of the test and mark water level. The test consists of a one-hour observation period. The absence of any water level drop during this period is considered a passing test. If the water level drops, the tank must be resealed and retested.
5. Cover: A utilized tank may not be covered until after the City of Richmond representative has conducted an inspection of the tank and its connections.
4.2 Inspection
The City of Richmond, consistent with applicable Contra Costa County Health Officer regulations, is responsible for inspecting various aspects of sewage systems to ensure
Temporary Sewage Holding Tank
City of Richmond
16 compliance with safety and operational standards. This step is integral to the operational requirements to ensure that sewage holding tank systems meet the required health and safety standards. Additional information regarding the operational requirements will be covered in the Permit Process Section.
1. Non-buoyancy in high groundwater areas or conditions;
2. Watertightness of the sewage holding tank, tested at site after installation, by filling with water;
3. Leak-proof nature of the service access(es), access ports, risers, lids, and covers;
4. Methods to secure the lids and covers from inappropriate or unapproved access;
5. Methods of venting provided by the design and installation. Venting should exhaust above the roof line of the building;
6. Equipment and methods for cleaning sewage spills; and
7. Alarm functions.
5.0 Operation and Maintenance Process
This section addresses the ongoing requirements for maintaining a functional sewage holding tank system. The operations and maintenance process details odor control measures for both gravity and pressure flow systems, workplace practices to prevent contamination, and proper procedures for wastewater removal and disposal. These guidelines help ensure safe operation and prevent environmental contamination throughout the system's service life.
5.1 Odor Control
The process outlines the necessary measures to control odors, ensure leak-proof seals, and properly vent sewage holding tanks in both gravity and pressure flow systems :
1. All covers must be leak-proof to prevent infiltration or exfiltration of liquid or the escape of nuisance odors or hazardous gases.
2. Gravity Flow to the Sewage Holding Tank: Separate venting directly from the sewage holding tank is required since gases will not adequately vent through the pressurized line from a sewage pump. Vent pipes should terminate at a height sufficient to ensure the dispersion of odors and gases, and must be located away from windows, doors, walkways, and other areas where human activity regularly occurs.
3. Pressure Flow to the Sewage Holding Tank: Direct venting of the sewage holding tank is required since gases will not adequately vent through the pressurized line from a sewage pump. Vent pipes must terminate at a height sufficient to ensure the dispersion of odors and gases, and must be located away from windows, doors, walkways, and other areas where human activity regularly occurs.
5.2 Good Workplace and Residential Practices
Proper handling and maintenance of the sewage holding tank are crucial to prevent contamination, support emergency response, and ensure safe operations. This subsection outlines key practices such as monitoring, labeling, and employee/household user traini ng for managing the sewage. The Basic Maintenance Checklist for Household Sewage Holding Tanks is shown in Appendix C.
Temporary Sewage Holding Tank
City of Richmond
17 1. The sewage holding tank must remain closed at all times except when sewage is being added or removed.
2. Conduct and document visual inspections of the sewage holding tank and piping for leaks. Document periodic tests of the sound and visual alarms, too.
3. Label the sewage holding tank or place a sign near the access cover with the words, " Non-Hazardous Sewage". The sign serves as a reminder for employees or household users and alerts emergency first responders unfamiliar with your business or household processes and practices.
4. Train employees or household users about spill prevention and clean-up to minimiz e the possibility of contaminants entering the sewage holding tank.
5. In the event of a leak or spill, there should be an appropriate response measure to collect, contain and clean-up the sewage. In the event of a chemical or oil spill, report the spill to the Department of Environmental Protection (DEP), even if the material is captured in the sewage holding tank. Refer to Appendix D for the Spill Response and Reporting Guideline.
6. No hazardous waste shall be deposited in the sewage holding tank.
5.3 Disposal Methods
This section outlines the requirements and procedures for the proper pumping and disposal of wastewater from sewage holding tanks. It covers the necessary access points for efficient pumping, the frequency of tank servicing, the method of sewage removal, and the requirements for disposal of hazardous waste:
1. Temporary Sewage Holding Tanks must be pumped at least once per week, or at a frequency demonstrated by metering or records to prevent the tank from exceeding 75% of working volume between pump-outs to avoid spills, backups, or nuisance conditions.
2. Removal of sewage from holding tanks shall be accomplished in a clean and sanitary manner, by means of a vacuum hose, and shall be disposed into a leakproof tank truck. In addition, a licensed sewage sludge hauler must obtain a Richmond Business License Number. Operators are also required to obtain a permit decal for their sewage pumping vehicles. The permit decal, as required by Section 420-6.1206 of Contra Costa County Ordinance Code 420-6.606, must be displayed permanently to the rear of the sewage pumping vehicle.
6.0 Notification Requirements
The notification requirements align with the permit processes, inspection requirements, and operational standards already established in the document, while ensuring proper oversight and emergency response capabilities for the temporary sewage holding tank systems throughout the City of Richmond.
6.1 Pre-Installation Notification
For the procedure of abandoning an onsite wastewater treatment system, the property owners must provide an advanced notification to the appropriate authorities before installing a sewage holding tank system:
Temporary Sewage Holding Tank
City of Richmond
18 1. City of Richmond Notification: Written notification must be submitted to the City of Richmond to schedule required inspections. Refer to the Permit Process Section for more detais about the Construction Permit.
2. Utility Notification: Coordinate with the utility companies (gas, electric, water, telecommunications) before the excavation.
6.2 Operational Notification
Ongoing notification requirements during system operation include:
1. Pumping Schedule: The licensed sewage sludge hauler must provide written notice to the property owner and City of Richmond after each pumping event. Refer to the Permit Process Section for more details about the Manifest System Process.
2. System Malfunctions: Any malfunction, leak, overflow, or failure of the sewage holding tank system must be reported immediately to the City of Richmond.
6.3 Emergency Notification
Immediate notification is required for any emergency situations:
1. Spills: Any sewage spill or release must be reported immediately to the City of Richmond.
2. System Failure: Complete system failure requiring emergency pumping or alternative arrangements must be reported within two hours to the City of Richmond.
6.4 System Modification or Abandonment
This subsection describes the notification requirements for modifying, abandoning, or converting a sewage holding tank system, including actions required when municipal sewer service becomes available.
1. Modifications: Any proposed modifications to the existing sewage holding tank system require an advance written notice to the City of Richmond. Refer to the Permit Process Section for more details about the Construction Permit Process.
2. Abandonment Notice: Property owners must provide an advance written notice before abandoning or converting a sewage holding tank system. Refer to the Permit Process Section for more details about the Abandonment Requirement.
3. Sewer Connection: When municipal sewer service becomes available, the City shall notify the affected property owners of the requirement to connect and initiate abandonment of the existing sewage holding tank system.
7.0 Abandonment Plan
This section outlines the procedures for properly decommissioning sewage holding tank systems, including both the removal and off-site disposal of the sewage holding tank and its contents, as well as the option for on-site abandonment (Contra Costa County Ord. Code § 420-6.606; Contra Costa County Health Officer Regulations for Sewage Collection and Disposal, 2018). The abandonment plan specifies the timeline requirements for system termination when connecting to permanent sewer infrastructure.
Temporary Sewage Holding Tank
City of Richmond
19 7.1 Removal and Off-Site Disposal of Sewage Holding
Tank and Contents
The City recommends prioritizing the removal and proper disposal of sewage holding tank systems, particularly those installed underground, to avoid potential confusion or issues for future property owners or tenants. Abandonment procedures for sewage holding tanks, with provisions for removing and disposing of materials off-site:
1. All contents must be removed from the sewage holding tank and hauled away by a licensed sewage sludge hauler.
2. The lid of the sewage holding tank must be removed and either recycled or disposed of at a permitted solid waste facility.
3. The sewage holding tank must be excavated, removed, and disposed of at a permitted solid waste facility or abandoned in place.
4. All above-ground appurtenances, including vents, risers, and electrical alarm systems, must be removed and disposed appropriately. Vents, risers, and electrical alarms could be disposed of in a solid waste landfill approved for construction and demolition debris.
7.2 On-Site Abandonment of Sewage Holding Tanks
Guidelines for in-place abandonment of sewage holding tanks as part of the abandonment process:
1. If the sewage holding tank is abandoned in place, a sufficient number of holes must be made in the bottom of the tank to prevent accumulation of surface water in or above the tank.
2. A sewage holding tank that is abandoned in place must be filled with pea gravel, drain rock, or compacted native soil.
3. Any remaining piping and valves must be cut and capped using corrosion-resistant and watertight plugs or refer to Section 3.4 Plumbing and Piping for the details of connecting to the City’s Sanitary Sewer without excavation of primary building sewer lines.
4. All electrical systems must be de-energized at the source unless repurposed for the sewer connection.
7.3 Abandonment Duration and Requirements
1. The property owner or agent shall apply for an abandonment requirement from the City of Richmond, consistent with applicable Contra Costa County Health Officer regulations, to abandon the existing onsite sewage system. Additional details about the abandonment requirement are provided in the Permit Process Section.
2. Use of a sewage holding tank system connected to a structure must terminate upon completion of construction of a new onsite wastewater treatment system that will serve the structure.
Temporary Sewage Holding Tank
City of Richmond
20 3. Use of a sewage holding tank system connected to a structure must terminate within 90 calendar days after the City of Richmond determines that connection to a sanitary sewer is available to the structure.
8.0 Transition Plan for Ultimate Sewer
Solution
This section establishes the requirements and procedures for transitioning properties utilizing temporary sewage holding tanks to a permanent sanitary sewer connection once service becomes available. This ensures an orderly and timely conversion process that minimizes service disruption, protects public health, and aligns long-term infrastructure goals for the City of Richmond.
8.1 Applicability
This transition plan applies to all properties operating under an approved temporary sewage holding tank permit in areas where a sewer moratorium is in effect and where future sewer infrastructure is planned and scheduled for construction.
8.2 Notice of Sewer Availability
When sewer service becomes available to a property:
1. The City will issue a formal written notice to the property owner identifying that a sewer connection is now possible.
2. The notice will include the connection location, construction timeline, and any applicable fees or design requirements.
3. Property owners will have a 90-day compliance period from the date of notice to initiate connection planning and abandon the sewage holding tank system.
8.3 Connection Requirements
Property owners must:
1. Hire a licensed contractor to complete the sewer connection in accordance with City design standards.
2. Obtain necessary permits for connection and abandonment of the sewage holding tank from the City of Richmond, as applicable. The permits include a Construction Permit, Operational Requirement, and Abandonment Requirement, which will be explained further in the Permit Process Section.
3. Ensure the sewage holding tank is properly decommissioned by Section 7.0 of this document.
8.4 Abandonment and Site Restoration
Once connected to the sewer:
1. The temporary sewage holding tank must be abandoned in place or removed in accordance with the abandonment guidelines.
2. Any related surface or sub-surface infrastructure (e.g., risers, vents, access points) must be removed, filled with pea gravel, drain rock or compacted native soil, or capped.
Temporary Sewage Holding Tank
City of Richmond
21 3. The site must be restored to grade and re-landscaped or repaved as appropriate to match adjacent conditions.
8.5 Documentation and Verification
Upon completion of the sewer connection and sewage holding tank abandonment, the property owner must submit the following to the City:
1. A Certificate of Lateral Compliance recommended by a state licensed plumber to be approved by the City of Richmond.
2. An Abandonment Requirement application. Refer to the Permit Process Section for more details about the Abandonment Requirement.
3. As-built drawings or photographs documenting both the new connection and the decommissioned sewage holding tank.
8.6 Failure to Transition
Failure to connect to the sewer system within the 90-day period may result in:
1. Revocation of the sewage holding tank Operational Requirements.
2. Enforcement actions in accordance with the Municipal Code Chapter 12.19, “Onsite Wastewater Treatment Systems”, including violations, penalties, discontinuance of service, and/or permit revocation, as applicable.
3. Municipal Code Chapter 12.19, “Onsite Wastewater Treatment Systems” is independent but coordinated with Contra Costa County Health Officer under Contra Costa County Ord. Code § 420-6.606, including referral to Contra Costa Health for potential citation, as appropriate.
8.7 Special Circumstances
If connection to the sewer cannot be completed within the designated timeframe due to conditions beyond the control of the property owner (e.g., access constraints, delayed construction by the City), the property owner may request a written temporary extension. All extension requests must:
1. Be submitted in writing before the original compliance deadline.
2. Include justification and a proposed schedule for compliance.
3. Be approved by the City of Richmond, consistent with applicable Contra Costa County Health Officer regulations on a case-by-case basis.
Temporary Sewage Holding Tank
City of Richmond
22 References
ACI Building Code Requirements for Structural Concrete and Commentary, https://myyardimci.weebly.com/uploads/1/6/3/4/16347790/building_design_code_engli s h.pdf, Accessed 6-19-2025
ASSE International, ASSE Standard #1013-2021 Reduced Pressure Principle Backflow Preventi on Assemblies, https://assewebstore.com/asse-standard-1013-2021/, Accessed 6-19-2025 ASTM C923 Standard Specification for Resilient Connectors Between Reinforced Concrete Manhole Structures, Pipes and Laterals, https://store.astm.org/c0923-00.html, Accessed 6- 10-2025
Barr, GRAF Heavy-Duty Septic Holding Tanks, https://www.barrplastics.com/products/graf- heavy-duty-septic-sewage-holding-tanks, Accessed 6-16-2025 California Building Standards Code, https://www.dgs.ca.gov/BSC/Codes, Accessed 6-3-2025 California Code of Regulations, Onsite Wastewater Treatment System, https://www.waterboards.ca.gov/water_issues/programs/owts/docs/appdxk_ch7ta1401. pdf, Accessed 6-20-2025
California Plumbing Code, Section 709 Gravity Drainage, https://crw.cityofoceanside.com/etrakit3/viewAttachment.aspx?ActivityNo=BLDG18- 1020&Group=PERMIT&key=PSC%3A1805300321424472, Accessed 6-20-2025 California Water Boards, California Code of Regulations, Title 23, Division 3, Chapter 16, https://www.waterboards.ca.gov/ust/regulatory/docs/ccr_ch16_202010.pdf , Accessed 6-17-2025
City of Richmond, Certificate of Lateral Compliance,
https://www.ci.richmond.ca.us/2269/Certificate-of-Lateral-Compliance . Accessed 7-21- 2025
City of Richmond Chapter 15.04 - Zoning And Subdivision Regulations, https://library.municode.com/ca/richmond/codes/code_of_ordinances?nodeId=ARTXV ZOSU_CH15.04ZOSURE_SERIES_100GEPR, Accessed 6-6-2025
City of Richmond, Landslide Potential Map,
https://www.ci.richmond.ca.us/DocumentCenter/View/8854/Map-121---Landslide- Potential?bidId=, Accessed 6-16-2025
City of Richmond, Liquefaction Potential Map,
https://www.ci.richmond.ca.us/DocumentCenter/View/8855/Map-122---Liquefaction- Potential?bidId=. Accessed 6-16-2025
City of Richmond Ordinance No. 09-19 N.S., An Ordinance of the Council of the City of Richmond, California, Amending Article XII of the Municipal Code of the City of Richmond, Accessed 6-11-2025
Temporary Sewage Holding Tank
City of Richmond
23 City of Richmond, Screening of Equipment,
https://library.municode.com/ca/richmond/codes/code_of_ordinances?nodeId=ARTXV ZOSU_CH15.04ZOSURE_SERIES_600GEST_ART15.04.601GESIRE_15.04.601.110SCEQ , Accessed 9-11-2025
City of Richmond, Chapter 12.19 Onsite Wastewater Treatment Systems, https://library.municode.com/ca/richmond/codes/code_of_ordinances?nodeId=ARTXIIP UWO_CH12.19ONWATRSY_12.19.030ADCOCOCOHEOFRESECODI, Accessed 1-19-2026 Contra Costa County, Contra Costa County Ordinance No. 2018-25, Accessed 5-22-2025 Contra Costa Hazardous Materials Programs, https://www.cchealth.org/health-and-safety- information/hazmat-programs, Accessed 6-3-2025
Contra Costa County, Health Officer Regulations for Sewage Collection and Disposal, Contra Costa County Ord. Cose 420-6.606, Accessed 5-22-2025
Environmental Protection Agency Onsite Wastewater Treatment Manual, https://www.epa.gov/sites/default/files/2015-
06/documents/2004_07_07_septics_septic_2002_osdm_all.pdf, Accessed 6-3-2025 Fiberglass Tank Solutions, Engineered Concrete Deadman System, https://fgtsolutions.com/wp- content/uploads/2025/05/Concrete-Deadmen-Cut-sheets-2025.pdf, Accessed 6-10-2025 Florida Health County, Temporary Holding Tank Application, https://lee.floridahealth.gov/programs-and-services/environmental-health/onsite- sewage-disposal/permits/holding-tanks.html, Accessed 5-22-2025 Holding Tank vs. Septic Tank: What’s the Difference, https://www.angi.com/articles/holding- tank-vs-septic-tank.htm, Accessed 6-10-2025
International Plumbing Code 2025, https://codes.iccsafe.org/content/IPC2024P1/chapter-7- sanitary-drainage#IPC2024P1_Ch07_Sec708, Accessed 6-20-2025 International Private Sewage Disposal, 2018 International Private Sewage Disposal Code, https://codes.iccsafe.org/content/IPSDC2018/chapter-8-tanks, Accessed 5-22-2025 Maine Department of Environmental Protection, Recommended Practices for Non-Hazardous, Industrial Wastewater Holding Tanks,
https://www.maine.gov/dep/water/wd/uic/holdingtanks.html Accessed 5-22-2025 Napa County, Holding Tanks and Hold and Haul Systems,
https://library.municode.com/ca/napa_county/codes/code_of_ordinances?nodeId=TIT 13WASEPUSE_CH13.52HOTAHOHASY, Accessed 5-22-2025
National Oceanic and Atmospheric Administration (NOAA), Damage-Resistant Practices for Designing Septic Systems in Coastal High Hazard Areas,
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Temporary Sewage Holding Tank
City of Richmond
24 Areas.pdf?rlkey=lwe0toedrzl6xm122e2i8c4vg&e=1&st=7g3sdgri&dl=0, Accessed 5-22- 2025
Protank 500 Gallon Above Ground Septic Holding Tank, https://www.protank.com/500gallon- aboveground-plastic-septic-holding-tank-p2742736, Accessed 6-11-2025 Sacramento County, Wastewater Holding Tank, https://ecode360.com/44028394 San Bernardino Environmental Health Services, Sewage Holding Tank Application Packet, https://wp.sbcounty.gov/dph/wp-content/uploads/sites/7/2022/02/Sewage-Holding- Tank-Application-Packet.pdf, Accessed 5-22-2025
Septic Tank: Types, Working Principle, Design, Size, Advantages & Disadvantages, https://testbook.com/civil-engineering/septic-tank-diagram-types , Accessed 6-02-2025 State of California, Waste Holding Tanks, https://www.law.cornell.edu/regulations/california/25- CCR-4517.8, Accessed 5-22-2025
State of Georgia, Code of Georgia Sewage Holding Tanks, https://law.justia.com/codes/georgia/title-12/chapter-15/article-1/section-12-15-5/, Accessed 5-22-2025
State of Vermont, Potable Water Supply and Wastewater System Permit, https://legislature.vermont.gov/statutes/section/10/064/01979, Accessed 5-22-2025 Texas Commission on Environmental Quality, Types of Municipal Solid Waste Processing and Disposal Facilities, and Wastes That May Be Accepted,
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Vector Solutions, Aboveground Storage Tank Requirements (AST), https://www.vectorsolutions.com/courses/aboveground-storage-tank-requirements-ast-/ , Accessed 6-10-2025
Washington State Department of Health, Department Standards and Guidance for Performance, Application, Design, and Operation & Maintenance: Holding Tank and Incinerator Sewage Systems,
https://doh.wa.gov/sites/default/files/legacy/Documents/Pubs/337-006.pdf, Accessed 5- 22-2025
Wieser Concrete Septic/Holding Tanks, https://wieserconcrete.com/product/septic-holding- tanks/, Accessed 6-11-2025
Wholesale Septic Supply, SP-400 Septic Tank Alarm with Float, https://www.wholesalesepticsupply.com/products/sp-400-septic-tank-alarm-with-floa t, Accessed 6-10-2025
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Temporary Sewage Holding Tank
City of Richmond
Appendix A
Keller Beach Sanitary Sewer (KBSS) Moratorium Area
8
6 8 " - 1 4 . 5 '
6 " - 3 5 '
8 " - 2 8 '
1 2 " - 3
7 '
6 " - 5 0 '
6 " - '
6 " - 4 8 '
6 " - 4 0 '
6 " - 7 3 '
6 " - 5
8 '
6 " - 6 5 '
8 " - 6 5 '
6 " - 5 5
'
6 " - 7 3 '
8 " - '
6 " - 7 2
'
6 " - 7 2
'
1 2 " - 7 3 '
6 " - 7 4 '
6 " - 7 0 '
6 " - 7 7 '
6 " - 1 3
3 '
6 " - 9 0 '
6 " - 1 0 0 '
8 " - 8 4 '
6 " - 8 7
'
6 " - 8 6 . 8 '
6 " - 9 3 '
6 " - 1
0 0 '
6 "
- 1 0 0 '
6 " - 1 0 3 '
6 " - 1
0 2 '
6 " - 8 1 '
6 " - 1 0 1 ' 6 " - 1 0 1 '
6 " - 9 9 '
6 " - 1 1 3 '
6 " - 1 0 0
'
6 " - 1 0 3 '
6 " - 1
0 5 '
6 " - 1 1
4 '
6 " -
1 0 4 '
6 " - 1 2 1 '
6 " - 1 2 2 '
2 1 " - 1 2 4 '
3 6 " - 1 3 0
'
6 " - 1 4 5 '
1 2 " - 1 2 7 . 9 '
2 1 " - 1 3 2 '
6 " - 1 3 3
'
6 " - 1 5 4 '
6 " - 1 3 4 '
6 " - 1 4 1 '
6 " - 1 3 9
'
6 "
- '
4 " - 1 4
6 '
6 " - 1 5
0 '
6 " - 1 4 9 '
8 " - 1 0
6 '
6 " -
1 3 7 . 5 '
6 " - 1 5 1 '
8 " - 1 5 0 . 5 '
6 " - 1 5 0
'
8 " - 1 5 2 '
8 " - 1 5 9 '
6 " - 1 5 5 '
6 " - 1 5 5 '
6 " - 2 5 7 '
8 " - 1 5 2 '
6 " - 1 6 5 '
6 " - 1 7 6
'
6 " - 1 7
0 '
6 " - 1 6 1 '
6 " - 1 7 2 '
8 " - 1 7 0 '
6 " - 1 7 5 '
1 2 " - 1 7 3 '
6 " - 1 7 6
'
6 " - 1 7 8 '
6 " - 1 8 1
'
6 " -
1 7 5 '
6 " - 1 5 7 '
6 " - 1 6 0 '
8 " - 3 4
4 '
1 0 " -
1 8 5 '
6 " - 1 9 6 '
6 " - 2 1
5 '
6 " - 1 7 5 '
8 " - 2 0 1 '
6 " - 2 0 0 '
8 " - 2 0
5 '
6 " - 2 1 6 '
6 " - 1
9 2 '
6 " - 1 9 3 '
1 0 " - 2 0 7 '
6 " - 2 2
0 '
3 9 " - 2 2 7 '
8 " - 2 1 9 '
6 " - 2 2 0 '
1 2 " - 2 1 8 '
6 " - 2 2 0 '
6 " - 2
1 8 '
1 6 " - 2 2 3 ' 6 "
- 2 0 1 '
6 " - 2 1 7 '
6 " - 2 3 5
'
6 " - 2 3 3 '
6 "
- 2 3 0 '
6 " - 2 3 5
'
6 " - 2
3 5 '
1 0 " - 2
4 6 '
1 2 " - 2
4 2 '
6 " - 2 4 4 '
6 "
- 1 4 5
'
1 0 " - 2 5 2 '
6 " - 2
5 4 '
6 " - 2 5 0 '
6 " - 2 3 9 '
6 " - 4 1 5 '
1 2 " -
2 6 1 '
8 " - 2 6 8 '
1 2 "
- 2 2 3 '
6 " - 2 6 3 '
8 " - 2 7 3 '
6 " - 2 6 3 '
1 0
" - 2 7
5 '
6 " - 2 8 0 '
6 " - 2 8 3 '
6 " - 2 4 3 '
6 " - 2 9 3
'
6 " - 2 8 8 '
6 " - 2 8 9 '
6 " - 2 9 0 '
6 " - 2 9 2 '
1 2 " - 2 9 2 '
1 0 " -
2 9 5
'
6 " - 2 9 5 . 3 8 '
6 " - 3 0 0 '
8 " - 3
0 1 '
1 2 " - 3 0 6 '
8 " - 3 0 8 . 5 4 '
6 " - 3 1 1
'
1 0 " - 2 9 7 '
6 " - 3 1 5 '
1 2 " - 3 2 8 '
6 " - 3 2 8 '
8 "
- 3 3 7 '
6 " - 3
6 3 '
1 2 " - 3 5 6 '
6 " - 3
4 6 '
8 " - 3 4 5
'
6 " - 4
0 0 '
6 " - 3 5 6 '
6 "
- 3 7
5 '
8 " - 3 6 9 '
6 " - 3 7 0 '
6 " - 3 7 1 '
1 2 " - 3 9 3 '
1 5 " - 4 5 4 '
6 " -
3 8 0 '
3 6 " - 4 0 6
'
1 2 " - 3 9 3
'
6 " - 4 0 9 '
6 " - 4 2 2 '
1 0 " - 4 2 2 '
3 6
" - 4 1
8 '
6 " - 4 3 4
'
3 6 " - 4 4 1 '
8 " - 4 5 6 '
6 " - 4
7 6 '
8 " - 2 5 0 '
1 2 " - 5 1 4 '
6 " - 5 1 8 '
2 1 " - 6 7 4 '
CASTRO
ST
TEWKSBURY AVE
PACIFIC AVE
GOLDEN
GATE
AVE
I 580
S
GARRARD
BLVD
CONTRA COSTA ST
WASHINGTON
AVE
W
RICHMOND
AVE
DORNAN
DR
MARIN
E ST
GRANDVIEW CT
WESTERNDR
SANTA
FEAVE
CR
EST AVE
BELVEDEREAVE
HIGHST
TREMONTAVE
LOBOS CT
CYPRESSPOINTRD
MARTINAST
CLA
REN
CE ST
SUM
MIT PL
LOBOSAVE
COTT
AGE AVE
SCENIC
AVE
BISHOP ALY
OCE
AN AVE
CASEYDR
NICHOLL
AVE
PIEDMONTPL
RAI
LR
OAD AVE
TUN
NEL A
VE
EDDYST
DELFINO AVE
PARK
PL
TERRACE
AVE
VINE AVE
ALL
EY
WATER ST
CHEVRON WAY
BISHOP AVE
F 7 S S 1
K e l l e r B e a c h
P u m p S t a t i o n
1 inch = 350 feet
0 350 700
Feet
Legend
Sewer Fitting
L a m p h o l e , A c t i v e
L a m p h o l e , P r i v a t e
L a m p h o l e , B u r i e d
O t h e r
W y e
Sewer Manhole
A c t i v e
B u r i e d
A b a n d o n e d
Sewer Structure
P u m p S t a t i o n
Sewer Force Main
F o r c e M a i n
Sewer Gravity Main
A c t i v e
R e l i e f
A b a n d o n e d
PUBLIC
WORKS
DEPARTMENT
KELLER BEACH LINE
P a r c e l L i n e s
Moratorium Parcels by Use Code
F o u r p l e x
S i n g l e f a m i l y , 1 r e s i d e n c e o n 2 o r m o r e s i t e s S i n g l e f a m i l y o n o t h e r t h a n s i n g l e f a m i l y l a n d S i n g l e f a m i l y r e s i d e n t i a l , d e t a c h e d , w / c o m m o n a r e a ( n o r m a l S u b d i v i s i o n t y p e P U D ) ; d u e t s w / c o m m o n a r e a S i n g l e f a m i l y , 2 o r m o r e r e s i d e n t i a l o n 1 o r m o r e s i t e s A t t a c h e d P U D s , c l u s t e r h o m e s , c o - o p s , c o n d o s , t o w n h o u s e s , e t c . D u p l e x
T r i p l e x
S i n g l e f a m i l y , 1 r e s i d e n c e o n 1 S i t e a n d D u e t s w / o c o m m o n a r e a s A p a r t m e n t s , 5 - 1 2 u n i t s , i n c l u s i v e R e s i d e n t i a l V a c a n t , 1 s i t e ( i n c l u d e s P U D s i t e s ) R e s i d e n t i a l V a c a n t , 2 o r m o r e s i t e s R e s i d e n t i a l V a c a n t , u n b u i l d a b l e I n d u s t r i a l V a c a n t L a n d ( n o t p a r t o f i n d u s t r i a l p a r k o r P . a n d D . ) N o D a t a
C o m m o n a r e a p a r c e l s i n P U D s ( o p e n s p a c e s , r e c r e a t i o n a l f a c i l i t i e s ) G o v e r n m e n t - o w n e d , w i t h o r w i t h o u t b u i l d i n g s ( f e d e r a l , s t a t e , c i t y , B A R T ) M i s c e l l a n e o u s i m p r o v e m e n t s , 1 s i t e J a n u a r y 2 0 2 2
Temporary Sewage Holding Tank
City of Richmond
Appendix B
Safe Harbor Minimum Requirements
Safe Harbor Minimum Requirements
City of Richmond
Safe Harbor Quick Selection List (Deemed-to-Comply)
A. Minimum Setbacks (from Table 1)
☐ Bays/streams/rivers/canals: 100 ft
☐ Ditches/culverts/ephemeral streams: 50 ft
☐ Lakes/reservoirs: 100 ft
☐ Depressions/low areas: 5 ft
☐ Cutbanks/fill banks/escarpments/embankments/natural bluffs: 10 ft ☐ Fill areas/unstable soil/unstable landforms/drainage swales: 10 ft ☐ Trees: 10 ft
☐ Structures/foundations: 10 ft
☐ Underground irrigation/drainage (watertight piping): 10 ft ☐ Underground irrigation/drainage (non-watertight piping): 100 ft ☐ Easements: 5 ft
☐ Public drinking water well: 100 ft
☐ Pressurized water supply line: 10 ft
☐ Rocky/fissured ground: > 50 ft (and greater than the nearest water supply siting distance)
B. Minimum Tank Sizing (Section 3.1)
☐ Residential (1–2 bedrooms): ≥ 1,000 gallons
☐ Residential (3+ bedrooms): ≥ 1,000 gallons for first 2 bedrooms + 250 gallons per additional bedroom
☐ Other structures: Minimum capacity = (peak daily sewage flow × 0.75) + 1,125 gallons
C. Minimum Pumping / Disposal Frequency (Section 5.3)
☐ Pumping: at least once per week, or frequent enough (per metering/records) to prevent exceeding 75% of working volume between pump-outs
D. Alarm Setpoint (Section 3.3)
☐ High-water alarm indicates the tank is approximately 75% filled
E. Materials (Table 2)
☐ Tank material (select one): Pre-cast concrete, fiberglass, or polyethylene ☐ Appurtenances: Risers, lids, seals/gaskets, and fittings are compatible with wastewater service and installed per manufacturer specifications.
Safe Harbor Minimum Requirements
City of Richmond
☐ Piping/Connections: Piping and fittings are compatible with wastewater service and installed per manufacturer specifications, consistent with the materials and limitations identified in Table 2.
Temporary Sewage Holding Tank
City of Richmond
Appendix C
Basic Maintenance Checklist for Household Sewage
Holding Tanks
Basic Maintenance Checklist for
Household Sewage Holding Tanks
City of Richmond
Weekly Checks
a. Check the tank alarm system
i. Ensure both the sound and visual alarms are working (they should go off when the tank is ~75% full).
b. Look for leaks or smells
i. Walk around the tank and nearby pipes. Report any foul odors or signs of leakage to the City of Richmond Public Works Department immediately. c. Inspect the access lid
i. Make sure the lid is tightly sealed and undamaged to prevent odors and pests.
Weekly Pumping
a. Schedule weekly pumping
i. Your tank must be pumped at least once per week to avoid overflow or odor problems.
b. Confirm the hauler provides a receipt or notification i. Keep a record of each pump-out for health and safety compliance.
Monthly Routine
a. Test the alarm system manually
i. Follow the alarm instructions to test it.
b. Inspect the tank label/sign
i. Ensure signage says, "Non-Hazardous Wastewater" (helpful in emergencies).
Safety Do’s and Don’ts
a. Do not flush hazardous materials.
b. Do not block access to the tank.
i. Make sure trucks can access the tank for pumping. Maintain a 10-foot clear area around it.
Emergency & Notifications
a. Report problems quickly
i. If there’s a leak, overflow, or system failure, notify the City of Richmond Public Works Department.
b. Inform new tenants/owners
i. If you sell or rent your home, let the new occupants know about the holding tank and share this checklist.
Temporary Sewage Holding Tank
City of Richmond
Appendix D
Spill Response and Reporting Guideline
Spill Response and Reporting
Guidelines
City of Richmond
Immediate Containment and Cleanup of Spills
a. Use Proper Safety Equipment and Cleanup Materials
i. PPE: gloves, boots, eye protection, disposable coveralls, mask. ii. Containment Equipment: absorbent pads, sandbags, plastic sheeting. iii. Cleanup Equipment: mop, bucket, EPA-registered disinfectant (i.e., bleach solution).
iv. Waste Handling Equipment: heavy-duty trash bags, sealed containers labeled as “Non-Hazardous”.
b. Steps for Containment and Cleanup
i. Secure the area to keep people away.
ii. Stop the spread of contaminated sources if safe to do so. iii. Contain the spill by surrounding the contaminated area with absorbents or sandbags to prevent the sewage from spreading.
iv. Once contained, clean the spill area using absorbents or sandbags to soak up the liquid.
v. Disposal of all non-hazardous waste at an approved site (no dumping into surface or groundwater).
vi. Decontaminate effected equipment with approved EPA-registered disinfectant.
vii. Wash hands thoroughly.
viii. If you ingest or come into direct contact with sewage or chemicals, immediately contact emergency medical services (911) for serious symptoms or Poison Control (1-800-222-1222) for guidance. For non- emergency exposures, contact your primary care physician, local health department, or an urgent care facility.
Report on the Spill
a. Notify the City of Richmond Public Works Department of the spill immediately or within 24 hours.
b. In the event of chemical spills, report the spill to the Department of Environmental Protection (DEP).
Manifest System for Sewage Waste Disposal
a. All waste from holding tanks, following spills, must be tracked using a manifest system to ensure safe and lawful disposal.
Emergency Plan Requirement for Spills
a. All holding tank systems must include a written emergency response plan that includes:
i. City of Richmond Public Works Department (510-620-5509 or [email protected]), and Sewage Hauler.
ii. Steps for sewage spills and procedures for containment, cleanup, reporting, and manifest system (Refer to Item 1 for procedural examples). The incident must be reported to the City of Richmond Public Works Department within 24 hours. All waste must be tracked through a manifest system documenting collection, transport, and final disposal at an approved facility, ensuring full accountability and regulatory compliance.
Temporary Sewage Holding Tank
City of Richmond
Appendix E
Landslide Potential Map
City of Richmond - Landslide Potential Map
Esri, NASA, NGA, USGS, FEMA, Sources: Esri, TomTom, Garmin, FAO, NOAA, USGS, © OpenStreetMap contributors, and the GIS User Community,
DOC/CGS
Landslide Susceptiblity Classes
0 III
V
VI
VII
VIII
IX
X
World_Hillshade
9/11/2025
0 1 2 0.5 mi
0 1.5 3 0.75 km
1:82,422
Temporary Sewage Holding Tank
City of Richmond
Appendix F
Liquefaction Potential Map
City of Richmond - Liquefaction Potential Map
Esri, NASA, NGA, USGS, Earthstar Geographics, Sources: Esri, TomTom, Garmin, FAO, NOAA, USGS, © OpenStreetMap contributors, and the GIS User Community
CGS Alquist Priolo Fault Traces
Accurately Located
Approximately Located
Inferred
Concealed
CGS Alquist-Priolo Fault Zones
CGS Liquefaction Zones
CGS Landslide Zones
CGS SHZ Unevaluated Areas
9/10/2025, 6:32:50 AM
0 1.5 3 0.75 mi
0 2.5 5 1.25 km
1:113,927