Legislation Details

File #: 2026-0970   
Type: Consent Calendar Item Status: Agenda Ready
File created: 8/21/2026 In control: Sonoma County Water Agency
On agenda: 10/6/2026 Final action:
Title: Modeling and Technical Support Services for Groundwater Sustainability Agencies
Department or Agency Name(s): Sonoma County Water Agency
Attachments: 1. Summary Report, 2. Attachment 1 - Amended Agreement with Errol L. Montgomery and Associates, Inc., 3. Attachment 2 - Prior Board Actions
Related files: 2024-0681, 2026-0620, 2021-0184, 2022-1177, 2023-1161

To: Board of Directors, Sonoma County Water Agency

Department or Agency Name(s): Sonoma County Water Agency

Staff Name and Phone Number: Brad Sherwood 707-547-1900, Marcus Trotta 707-547-1978

Vote Requirement: Majority

Supervisorial District(s): Countywide

 

Title:

Title

Modeling and Technical Support Services for Groundwater Sustainability Agencies

End

 

Recommended Action:

Recommended action

Authorize Sonoma County Water Agency’s General Manager or designee to execute the Third Amended and Restated Agreement for Modeling and Technical Services Support for Santa Rosa Plain, Sonoma Valley, and Petaluma Valley Groundwater Sustainability Agencies with Errol L. Montgomery & Associates, Inc., in substantially the form as the draft presented to this Board.  The amended agreement increases the amount by $256,370 and expands the scope of work to include supplemental assistance with periodic evaluations, meeting coordination and attendance, and groundwater sustainability plan amendment support and review for Sonoma Valley Groundwater Sustainability Agency, for a new not-to-exceed agreement total of $2,041,370 and no change to end date of June 30, 2027.

end

 

Executive Summary:

Sonoma County Water Agency (Sonoma Water) provides technical services to the three groundwater sustainability agencies (GSAs) established in June 2017: Santa Rosa Plain GSA, Sonoma Valley GSA, and Petaluma Valley GSA.  The subject agreement will provide Sonoma Water with the necessary expertise to provide these services.  The cost of services for the subject agreement will be reimbursed to Sonoma Water by the Petaluma Valley, Santa Rosa Plain, and Sonoma Valley GSAs.

 

Discussion:

HISTORY OF ITEM/BACKGROUND

On April 25, 2017, the Sonoma County Board of Supervisors and Sonoma Water Board of Directors authorized joint powers agreements for the formation of the GSAs.  Staff from the eligible agencies, as defined by the Sustainable Groundwater Management Act (SGMA), cooperated to develop a governance structure for these agencies.  Each of the three basins has a separate GSA with a board made up of elected or appointed board members from eligible agencies.

 

The GSAs were tasked with assessing the conditions in their basins and adopting locally based groundwater sustainability plans by January 31, 2022.  Under previous agreements authorized by the Sonoma Water Board of Directors (Board), Sonoma Water provided technical and outreach services associated with developing and implementing the groundwater sustainability plans (GSPs), which were approved by California Department of Water Resources (DWR) in 2023.  Following the GSP approval in September 2023, the three GSAs were awarded grant funding under DWR’s SGMA Round 2 Implementation Grants, which supported filling data gaps, planning and implementation of water use efficiency programs, planning for recharge projects, design and construction of recycled water infrastructure and outreach and stakeholder engagement programs.

 

Sonoma Water first entered into an agreement with Errol L. Montgomery & Associates, Inc. (Montgomery & Associates) for hydrogeologic technical support and computer modeling services to support the implementation of the GSPs in the amount of $200,000 and a term end date of June 30, 2024.  At the same time as the Board authorized execution of this agreement, it also provided authorization for Sonoma Water’s General Manager to amend the agreement with Montgomery & Associates to extend the term, make modifications to the scope of work, and increase costs up to a cumulative total of $350,000. 

 

A first amended agreement extended the term by three months to September 30, 2024, at no additional cost to Sonoma Water.

 

A second amended agreement, approved by the Board on July 9, 2024, increased the agreement amount by $1,585,000 for a new not-to-exceed total of $1,785,000, expanded the scope of work to include additional studies, monitoring, assessment, and reporting, and extended the agreement term by two years and nine months to June 30, 2027.

 

Work completed to date under this agreement includes development of the groundwater model update work plan; implementation of updates to the models; development and implementation of work plans for filling data gaps related to interconnected surface water and groundwater-dependent ecosystems and seawater intrusion; development and implementation of work plans for an updated well inventory and voluntary flow metering program; and initial support for drafting Periodic Evaluations for each GSA.

 

SELECTION PROCESS

Montgomery & Associates was selected on February 22, 2023, through a competitive selection process conducted for the original agreement. A new competitive selection process was not conducted because this amended agreement covers updates to technical services already in progress, not a new scope of services.

 

SERVICES TO BE PERFORMED

Under the proposed amended agreement, Montgomery & Associates will continue to provide hydrogeologic technical support and computer modeling services to support the implementation of the groundwater sustainability plans.  Additionally, the following services are being added to the scope, which will support periodic evaluations of the groundwater sustainability plans which are required to be submitted to DWR by January 2027:  assistance with the development of Periodic Evaluation sections and figures, coordinating and attending GSA staff and GSA advisory committee meetings, and supporting the development and review of the amendment to the GSP for the Sonoma Valley GSA.

 

The additional cost is $256,370, for a new not-to-exceed agreement total of $2,041,370.  There is no change to the end date of June 30, 2027.

 

County of Sonoma Strategic Plan Alignment:

N/A

 

Sonoma Water Strategic Plan Alignment

Goal:  Planning and Infrastructure

Strategy:  Conduct planning that integrates and balances operational, maintenance, and infrastructure priorities.

The GSAs’ mission is to manage the groundwater supplies, which are relied upon by numerous stakeholders including Sonoma Water and its water contractors in the Sonoma Valley, Petaluma Valley, and Santa Rosa Plain groundwater basins to achieve sustainable groundwater conditions.

 

Racial Equity:

Was this item identified as an opportunity to apply the Racial Equity Toolkit?

No

 

Racial Equity:

 

Was this item identified as an opportunity to apply the Racial Equity Toolkit?

No

 

Prior Board Actions:

See Attachment 2

 

Fiscal Summary

 Expenditures

FY26-27 Adopted

FY27-28 Projected

FY28-29 Projected

Budgeted Expenses

$256,370

 

 

Additional Appropriation Requested

$

 

 

Total Expenditures

$256,370

 

 

Funding Sources

$

 

 

General Fund/WA GF

$256,370

 

 

State/Federal

$

 

 

Fees/Other

$

 

 

Use of Fund Balance

$

 

 

General Fund Contingencies

 

 

 

Total Sources

$256,370

 

 

 

Narrative Explanation of Fiscal Impacts:

Budgeted amount of $256,370 is available from FY 2026/2027 appropriations for the Sonoma Water General 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:  Amended Agreement with Errol L. Montgomery and Associates, Inc.

Attachment 2:  Prior Board Actions

 

Related Items “On File” with the Clerk of the Board:

None.