1401 Fulton Street, Suite 802
Fresno, California 93721
P. 559-436-6616 / F. 559-436-1191
carollo.com
00030086 / Solids Handling Improvements_SOW_12_8_20 23.docx December 8, 2023
Mr. Nick Bartsch
City of Visalia
Public Works Department
336 North Ben Maddox Way
Visalia, CA 93292
Subject: Water Reclamation Facility – Solids Handli ng Improvements Design Dear Mr. Bartsch:
Enclosed is a Scope and Fee prepared by Carollo Eng ineers, Inc. (Carollo), to evaluate the City of Visalia (City) Water Reclamation Facility (WRF) to design an impro ved Thickened Sludge Pump Station (TWAS), additional screw press and sludge drying beds, and a new sludg e holding reservoir.
Project Background
The WRF currently uses gravity belt thickeners (GBTs) to thicken waste activated sludge. These GBTs were designed to produce thickened waste activated sludg e (TWAS) up to 5 percent total solids (TS). However, the plant has run into issues with the TWAS pumps tripp ing from too high of pressure when the TWAS is thickened to 5 percent TS. Therefore, the GBTs are operated to produce TWAS with about 2.5 percent TS, resulting in a significantly higher sludge flows being sent to the plant’s digesters. Since the capacity of the diges ters is currently limited by the hydraulic retention time and not the solids loading rate, this additional sludge flow being sent to the digesters directly reduces the overall digestion capacity.
Replacing the TWAS pumps with new pumps that can accommodate higher pressures would allow the GBTs to be operated as originally designed and produce TWAS with 5 percent TS. Sending less TWAS to the digesters would restore some of additional digestion capacity for accommodating additional increases in flows and loads, resulting in delaying the need for an additional digester and providing more time for the design and construction of the new digester and dewatering upgrades.
The thickening limitations causes excess flows thro ugh digestion, which requires the facility to run both dewatering screw press units under high loading per iods . There is currently no additional sludge storage or redundancy on the dewatering units, should maintena nce or potential failure occur on one of the dewatering units. This design will add one additional screw press, polymer tank, polymer feed pumps, and electric al equipment for a fully operational third screw press.
Due to the high influent loadings currently seen at the facility, the sludge drying beds are not large enough to keep up with the drying time needed for the biosoli ds. In addition, timing of sludge removal with wet weather has become difficult and resulted in higher hauling costs. The initial investigation will include an analysis of hauling costs with and without the installation of a dry sludge storage cover (for the stockpile area only) to see if constructing a covered area adds value to the City. This design will incorporate a new sludge drying b ed adjacent to the existing beds to allow for handling of the additional sludge loads. The sludge beds will be designed around the 4.5 acre space adjacent to the existing beds. Design of sludge drying covers will be under a separate contract if warranted through the results of the an alysis.
Mr. Nick Bartsch
City of Visalia
Public Works Department
December 8, 2023
The WRF currently struggles with maintenance on the ir digesters due to the lack of redundancy for taking a digester offline. This design includes the construc tion of a lined sludge pond that can be utilized during the dewatering of a digester for cleaning and maintenan ce. The pond will be approximately 4 acres of surface area.
A summary of the project design elements are as fol lows:
• Design for the installation of two new sludge booster pumps needed to convey TWAS at 5% to the digesters.
• Design of a third dewatering screw press to match existing. This includes a new polymer tank, polymer pumps, electrical equipment, and conveyor modifications. • Design of a new sludge drying beds (approximately 4 .5 acres total) • Design of a new lined sludge pond (approximately 4 acres) to allow for diverting/dewatering a digester for maintenance and approximately 1,400 linear feet of piping for dewatering.
SCOPE OF WORK
The following scope of work represents our understa nding of the necessary design elements to design the new facilities as described above. These facilities include: TWAS pumping upgrades, new screw press, sludg e drying bed, and digester cleaning sludge holding reservoir. The Design shall consist of CAD generated drawing s and specifications covering general civil and site work improvements, structural, mechanical, electrical, instrumentation and controls. The Design shall include layouts and schematics drawn to scale, design criteria and notes showing the proposed design of all new and mo dified existing facilities.
TASK 1: PROJECT MANAGEMENT AND MEETINGS
Project Management will include supervision of the project team, making sure the project is adequately staffed, and communication with the City staff. This task also includes management of the project budget and sc hedules, preparation of a monthly progress report, and incor porating Carollo’s quality management oversight and quality control to document processing and deliverables.
Meetings will be hybrid meetings or remote meetings , where Carollo staff will call in remotely. Meetings will include:
1. Project Kick-off Meeting (1 meeting) (PIC, PM, and PE onsite, other staff virtual).
2. Design update meetings (4 meetings held remotely)
3. Design workshop (60% design level)
4. Design workshop (90% design level)
Deliverables:
Monthly progress reports, including budget and sche dule updates. Meeting agendas and minutes. (All provided in PDF format).
TASK 2 - PREDESIGN
Task 2.01 – Confirm Design Elements
Mr. Nick Bartsch
City of Visalia
Public Works Department
December 8, 2023
This task includes analysis on existing TWAS Pump S tation to determine if modifications can be made to the existing pumps or if a new PS is needed. This task will incl ude using design data and findings from the Facilit y/Master Plan updates to design facilities for a new screw press, preliminary sizing, design criteria, and layouts f or the new sludge drying beds, and new sludge holding pond with assoc iated pipeline. This task includes a constructabili ty and sequencing evaluation to confirm the required project componen ts are included to construct the new TWAS pump stat ion and screw press train while minimizing impacts to cost and the operation of the existing pump station.
Included in this task is a geotechnical investigati on to determine updated structural requirements to meet the latest building code. Costs include coordination, investig ation, and geotechnical report.
Task 2.02 - Prepare Basis of Design Report (DRAFT)
A Basis of Design Report (BODR) will be prepared to summarize the results of Task 2.01 – Confirm Design e lements.
Task 2.03 - Basis of Design Workshop
A workshop to review the Basis of Design Report (DR AFT) will be chaired by CONSULTANT. The results of Task 2.01 – Confirm Design Elements will be presented and selec t responses to City comments reviewed. The ultimate goal of this meeting is to receive buyoff of the project compone nts to include in final design.
Task 2.04 - Prepare Basis of Design Report (FINAL)
City comments to the Basis of Design Report (DRAFT) and input from the Basis of Design Workshop will b e incorporated to prepare the Basis of Design Report (FINAL). Resp onses to comments will be prepared and submitted fo r acceptance.
Task 2 Assumptions:
• Project components to be included in final design w ill be finalized during the Basis of Design Worksho p. Any changes in the items to be designed after this work shop will be considered additional scope and may re sult in budget increases.
• CONSULTANT will prepare the agenda and meeting minu tes for the Basis of Design Workshop. • Comments to technical memoranda and the Basis of De sign Report (DRAFT) will be tabulated when transmitted to CONSULTANT.
• Each deliverable will be internally reviewed prior to submitting to the City. • Geotechnical report will be required for use in the predesign and final design tasks. 2 borings assumed • City will furnish a topographic survey from recent dewatering installation. • City will furnish sludge pump data (including recor d drawings) to use for designing the new pump units .
Task 2 Deliverables:
• One (1) hard copy and one electronic pdf file of th e Basis of Design Report (DRAFT) will be submitted. • One (1) hard copy and one electronic pdf file of th e Basis of Design Report (FINAL) will be submitted. • Meeting minutes (electronic)
• Geotechnical Report
TASK 3 – FINAL DESIGN
Task 3.01 - Develop 60% Plans, Specifications, and Estimate (PS&E) Submittal Package With the approval of the Basis of Design, the devel opment of a 60% PS&E document submittal package will be completed under this task. This task includes the d evelopment of an estimate of probable construction costs (AACE Mr. Nick Bartsch
City of Visalia
Public Works Department
December 8, 2023
Class 2). Additionally, a BODR Review Comment log wi ll be completed to log all of the City staff commen ts and responses from the CONSULTANT. One (1) copy of the plans, specifications, and estimate will be provide d to the CIty for review. A submittal review workshop to discuss comments on the 60% PS&E submittal package will be conducted at the end of the City review period.
Task 3.02 - Develop 90% PS&E Submittal Package
Comments from the 60% review workshop will be incorp orated into the 90% design deliverable. One (1) hard copy of the plans, specifications, and estimate will be pro vided to the City for review. A submittal review wo rkshop to discuss comments on the 90% PS&E submittal package will be co nducted at the end of the City review period.
Task 3.02 - Develop Bid Documents
Development of a Bid Document submittal package wil l be completed under this task. This task includes the development of an estimate of probable construction costs (AACE Class 2). Additionally, a 90% Design Revi ew Comment log will be completed to log all City staff comments and responses from the CONSULTANT. One (1) copy of the plans, specifications, and estimate will be pro vided to the City for bidding.
Task 3 Assumptions:
• The design scope and associated fee estimate are ba sed on the project elements identified under the PROJECT BACKGROUND section of this scope of work. Should the project elements be modified during the predesign tasks, then a modified scope of work and fee estima te will be prepared and submitted to City for revie w and approval prior to proceeding.
• Each deliverable will be internally reviewed with a Carollo QA/QC process prior to submitting to the City. • Assumes one city building/planning department revie w.
Task 3 Deliverables:
• 60% PS&E Submittal. (one (1) hard copy (11x17 drawings) an d one (1) PDF electronic file) • 90% PS&E Submittal. (one (1) hard copy (11x17 drawings) an d one (1) PDF electronic file) • Bid Document PS&E Submittal. (one (1) hard copy (22x34 d rawings) and one (1) PDF electronic file) • 60% Comment Log with responses.
• 90% Comment Log with responses.
TASK 4 – BID PHASE SERVICES
Task 4.01 – Attend Pre-Bid Meeting
Under this task, Carollo will attend a pre-bid meet ing to answer questions and discuss the overall pro ject intent. The City will facilitate this meeting and issue meeting minutes.
Task 4.02 – Answer Bidder Questions/ Provide Addend a
This task includes providing assistance to the City during the bidding period. The scope of work inclu des responding to bidders’ questions, preparing addenda to the contra ct documents during the advertisement period, and p roviding ongoing consultation and interpretation of the cons truction documents.
Task 4 Deliverables:
• Addendum as required (three assumed).
Task 4 Assumptions:
Mr. Nick Bartsch
City of Visalia
Public Works Department
December 8, 2023
• Carollo will attend a single pre-bid meeting facili tated by the City. • Carollo will prepare up to three addenda.
OPTIONAL TASK 5 - ENGINEERING SERVICES DURING CONST RUCTION (ESDC) Task 5.01 - Attend Pre-Construction Conference
Carollo will attend the pre-construction conference and answer questions as directed by the City. The City’s construction manager (CM) will prepare meeti ng minutes. Carollo will review meeting minutes.
Task 5.02 - Review Contractor’s Submittals
This task will include review and comment on the ac ceptability of contractor’s submittals for the City .
Carollo will review and respond to product and shop drawing submittals provided by the contractor and forwarded by the CM. Review comments will be return ed to the CM for processing and distribution to the contractor and other parties. 100 submittals are budge ted.
Task 5.03 - Respond to Requests for Information (RFIs)
Carollo will respond to contractor’s RFIs. This sco pe also assumes the CM will consider and evaluate t he validity of the RFIs, questions, and modification r equests prior to forwarding them to Carollo. Per th e RFP, 50 RFIs are budgeted.
Task 5.04 - Attend Construction Meetings and Site V isits Carollo will attend bi-weekly construction meetings (teleconference anticipated), conduct site visits (a total of ten site visits budgeted) to monitor constructi on progress, and remain available to expedite resolutions to project challenges.
Task 5.05 - Review Proposed Change Orders
Carollo will review changes in project scope and/or schedule, as requested by the CM. Carollo’s scope of work will include review of the contractor-furnished supporting information; discussions with contract or and CM in the field; and preparation of technical d ocuments—including supplemental drawings, specifications, etc.—to assist the CM with the prep aration of change orders.
Task 5.06 - Provide Record Drawings
The contractor is required to provide the City and CM with a final set of marked-up design drawings. A fter substantial completion, Carollo will review the final version of the contractor’s as-built drawings c ompiled by the CM. Carollo will then prepare a set of recor d drawings based on the contractor’s mark-ups in electronic format and deliver the electronic docume nts to the City. Record drawings will be prepared using Carollo’s standard record drawing format.
Mr. Nick Bartsch
City of Visalia
Public Works Department
December 8, 2023
Task 5 Assumptions:
• Budgeted up to 100 submittals
• Budgeted up to 40 RFI’s
• Budgeted up to 5 change order requests.
TIME OF PERFORMANCE
The completion of the design and bid support servic es will be performed within 12-months from the notice to proceed.
LEVEL OF EFFORT
The project design elements (Task 1 through Task 4) above will be completed for a lump sum fee of six hundred and eighty-three thousand, six hundred dollars ($68 3,600). Task 5- Engineering Services During Construction is estimated at two hundred and three thousand, six hu ndred dollars ($203,600) and will be negotiated prior to the award of bid.
We appreciate the opportunity to provide this scope and fee for this emergency project. Please reach out for any questions or negotiation on this proposal.
Sincerely,
CAROLLO ENGINEERS, INC.
Ryan Sellman, PE Reace Fisher, PE
Principal-in-Charge Project Manager
Attachments: Fee Proposal, Fee Schedule
CAROLLO ENGINEERS, INC.
FEE SCHEDULE
As of January 1, 2024
California
Hourly Rate
Engineers/Scientists
Assistant Professional $214 .00
Professional 232.00
Project Professional 270.00
Lead P roject Professional 312 .00
Senior Professional 343.00
Technicians
Technicians 186.00
Support Staff
Document Processing / Clerical 149.00
Subconsultant cost + 10%
Other Direct Cost cost + 10%
Expert Witness Rate x 2.0
This fee schedule is subject to annual revisions due to labor adjustments.
Task Task Description
1.1 $37,200
$37,200
2.1 $66,400
2.2 $49,800
2.3 Basis of Design Workshop $11,200
2.4 $20,300
$147,700
3.1 $126,900
3.2 $227,800
3.3 $94,400
$449,100
4.1 $6,400
4.2 $23,100
4.3 $20,100
$49,600
Design Subtotal $683,600
5.1 $6,000
5.2 $78,300
5.3 $41,200
5.4 $18,500
5.5 $15,200
5.6 Provide Record Drawings $44,400
$203,600
Total Project Costs: $887,200
Notes:
2. Geotechnical investigation based on two borings. Team to confirm number of borings and associated costs.
3. Budget is based on a 12-month completion schedule.
1. Budget is based on an estimated level of effort based on our interpretation of the project requirements based on initial discussions with the Owner. The final scope can be negotiated with the Owner to meet their needs.
Respond to Requests for Information
Attend Construction Meetings and Site Visits
Review Proposed Change Orders
Task 5 Total Costs:
Task 4 Total Costs:
OPT Task 5: Engineering Services During Construction (To Be T&M) Attend Pre-Construction Conference
Review Contractors Submittals
Task 3 Total Costs:
Task 4: Bid Support Services
Attend Pre-bid Conference
Answer Bidder Questions
Bid Adenda (3)
Develop 60% PS&E Submittal Package
Develop 90% PS&E Submittal Package
Develop Bid Documents
Task 2 Total Costs:
Task 3: Final Design
Confirm Desing Flows and Finalize Project Elements
Prepare Basis of Design (Draft)
Prepare Final Basis of Design
Task 1 Total Costs:
Task 2: Predesign
Project Management and Meetings
Task 1: Project Management and Meetings
FEE
WATER RECLAMATION FACILITY - SOLIDS HANDLING IMPROVEMENTS PROJECT
CITY OF VISALIA
December 7, 2023
Total Cost
(1,2)