To: Board of Directors, Sonoma County Water Agency
Department or Agency Name(s): Sonoma County Water Agency
Staff Name and Phone Number: Aaron Fulton 707-547-1974
Vote Requirement: Majority
Supervisorial District(s): Countywide
Title:
Title
Cotati No. 3 Tank Rehabilitation Project
End
Recommended Action:
Recommended action
Authorize Sonoma County Water Agency’s General Manager to execute an agreement with Harper & Associates Engineering, Inc., in a form approved by County Counsel, for engineering and design services through December 31, 2025, in the not-to-exceed amount of $150,000.
end
Executive Summary:
The Cotati No. 3 Tank Rehabilitation Project (Project) is a part of Sonoma County Water Agency's (Sonoma Water) overall Tank Maintenance Program (Program) - an essential element of Sonoma Water’s Capital Improvement Plan (Plan) that protects the transmission system’s 18 above-grade welded steel tanks through targeted proactive maintenance actions, structural repairs, and cathodic protection systems. The Project includes design, environmental compliance, and construction activities to maintain the functional life of the Cotati No. 3 tank, and will require highly specialized tank inspection, assessment, repair, and recoating design services.
Discussion:
HISTORY OF ITEM/BACKGROUND
Sonoma Water’s Plan identifies key infrastructure projects to meet the needs of the water system, wastewater districts, and flood management facilities within its jurisdiction. The Plan describes the infrastructure projects that are planned over the next five years and includes the Program with a goal to maintain and protect the 18 above-grade welded steel water storage tanks in Sonoma Water’s transmission system. Water storage tanks are an integral component of the water transmission and supply system that provide a source of water when demand rates exceed production capacity. In total, Sonoma Water’s 18 tanks provide approximately 129 million gallons of storage, which is three times the average daily system demand.
Sonoma Water’s average tank age is approaching 40 years. Without intervention, welded-steel tanks are susceptible to corrosion and have a limited functional lifespan of 25 to 50 years without recoating. With regularly scheduled and targeted maintenance and monitoring activities, welded-steel water storage tanks can attain a lifespan of up to 100 years. Sonoma Water’s Program specifically targets the protection and maintenance of steel tanks by routinely inspecting, cleaning, and monitoring the condition of each tank to identify needs and deficiencies. When inspections and monitoring indicate more substantial rehabilitation efforts are required or as coatings reach end of useful life, Sonoma Water develops design plans and tank rehabilitation projects that include recoating, structural repairs, and installation of cathodic protection systems to maximize the functional life of the facility.
The Cotati No. 3 tank was constructed in 1993 and has a capacity of 18 million gallons. Cotati No. 3 Tank is located on the Cotati Intertie Aqueduct west of the City of Cotati. The interior last received warranty repairs in 1998, and the exterior paint is original. Recent dive inspections and observations from staff indicate Cotati No. 3 tank needs coating and paint removal and replacement, repair of corroded structural elements, and structural modifications to preserve the original design life of the structure. Sonoma Water began the Project to rectify these deficiencies and meet the goals of the Program.
The Project will restore the Cotati No. 3 tank to its original character and condition, protect against premature structural failure, and maximize facility lifespan. The Project will include design, environmental compliance, and construction with significant support from a highly specialized coating inspection and tank rehabilitation design consultant.
SELECTION PROCESS
Harper & Associates Engineering, Inc. (Consultant) was selected from a list of qualified consultants developed from a competitive selection process. Attached is a memo that explains the competitive selection process.
Consultant was selected for the subject work because of its expertise and considerable experience conducting welded-steel water tank inspections, assessments, and rehabilitation designs for structural repairs and coating reapplications. Consultant has recently completed a similar sized water tank recoating project for Sonoma Water’s Cotati No. 1 and Kastania tanks.
Sonoma Water may seek to amend or enter into subsequent agreement(s) with Board approval if required, relying upon this competitive selection process, after the preliminary or initial work is completed for the Project.
SERVICES TO BE PERFORMED
Under the agreement, Consultant will conduct meetings; submit monthly progress reports; gather and review existing data; conduct field investigations to assess the condition and status of the tank for structural, safety, and coating conditions; develop a design report with recommended actions; submit 50%, 90%, 99%, and final engineering designs for the Project; and provide bid period and construction period services.
The cost of services will not exceed $150,000; the term end date is December 31, 2025.
The agreement includes authorization for the General Manager to make changes to lengthen time schedules or make minor modifications to the scope of work, which do not increase the amount paid under the agreement, in a form approved by County Counsel.
The agreement includes two options for Sonoma Water to extend the term for a period of one year each by providing written notice to Consultant thirty days in advance of the expiration date of the agreement and of the first extension option. The extension will be formalized in an amended agreement or amendment signed by Sonoma Water and Consultant.
Strategic Plan:
N/A
Sonoma Water Strategic Plan Alignment
Water Supply and Transmission System, Goal 2, Strategy No. 3 - Fund and implement the planned capital and maintenance projects on schedule to ensure reliable services.
The project will include design of targeted maintenance activities that protect the Cotati No. 3 tank from premature failure and will therefore improve the reliability and resilience water storage facilities along the transmission system.
Prior Board Actions:
11/16/2021: Approved agreement between Sonoma Water and Harper & Associates Engineering, Inc. for engineering and design services of Cotati No. 1 and Kastania Reservoir Rehabilitation. Cost $300,000; term end December 31, 2024.
Fiscal Summary
|
Expenditures |
FY 22-23 Adopted |
FY23-24 Projected |
FY 24-25 Projected |
|
Budgeted Expenses |
$150,000 |
|
|
|
Additional Appropriation Requested |
|
|
|
|
Total Expenditures |
$150,000 |
|
|
|
Funding Sources |
|
|
|
|
General Fund/WA GF |
|
|
|
|
State/Federal |
|
|
|
|
Fees/Other |
$150,000 |
|
|
|
Use of Fund Balance |
|
|
|
|
Contingencies |
|
|
|
|
Total Sources |
$150,000 |
|
|
Narrative Explanation of Fiscal Impacts:
Budgeted amount of $110,000 is available from FY 2022/2023 appropriations for the Water Transmission fund. Budgeted amount of $40,000 is available from FY 2022/2023 appropriations for the Storage Facilities fund. No additional appropriation is required.
|
Staffing Impacts: |
|
|
|
|
Position Title (Payroll Classification) |
Monthly Salary Range (A-I Step) |
Additions (Number) |
Deletions (Number) |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Narrative Explanation of Staffing Impacts (If Required):
N/A
Attachments:
Attachment 1: Selection Memo
Related Items “On File” with the Clerk of the Board:
None