For City Council Meeting September 22, 2026
TO: Honorable Mayor and City Council
FROM: Tanya Williams, City Manager
AUTHOR: Yazdan Emrani P.E., Director of Public Works
Title
Request City Council/Rialto Utility Authority to: (1) Approve the Cost Share Agreement With San Bernardino Valley Municipal Water District for Salt and Nutrient Management Planning Phase 3A, in an Amount Not-to-Exceed $29,405; and (2) Authorize the City Manager/Executive Director or Their Designee to Execute all Related Documents.
Body
RECOMMENDATION
Staff recommends that the City Council/Rialto Utility Authority:
1) Approve the cost share agreement with San Bernardino Valley Municipal Water District for Salt and Nutrient Management Planning (SNMP) Phase 3A, in an amount not-to-exceed $29,405; and
2) Authorize the City Manager/Executive Director or their designee to execute all related documents.
BACKGROUND
The Upper Santa Ana River Watershed contains interconnected groundwater basins that provide an important water supply to communities throughout the Inland Empire. Water quality objectives for salt and nutrients, including total dissolved solids (TDS) and nitrate, are established by the Santa Ana Regional Water Quality Control Board (Regional Board) through the Santa Ana River Basin Plan.
Regional water agencies and stakeholders have collaborated through the Salt and Nutrient Management Plan (SNMP) Work Group to evaluate cumulative impacts to groundwater quality and support implementation of water supply, recycled water, stormwater capture, recharge, and other water resource management projects. The City of Rialto has previously participated in the regional SNMP technical effort. In February 2021, the Rialto City Council agreed to pay Rialto's proportionate share of costs associated with the Phase 1 and Phase 2 SNMP technical studies.
SNMP Phase 1 and Phase 2
Water Systems Consulting, Inc. (WSC), together with its Geoscience team, was selected in 2021 to perform the Upper Santa Ana River Watershed Salt and Nutrient Management Strategy Study. The study consisted of three phases: Phase 1 - Water Quality Characterization; Phase 2 - Project Planning and Impact Analysis; and Phase 3 - Development of the SNMP. Phases 1 and 2 were completed and included technical memoranda addressing modeling.
The Phase 2 modeling used the Integrated Santa Ana River Water Quality Model to evaluate various projects and management strategies. The modeling projected TDS conditions through 2045 and estimated that approximately 20 percent of the available TDS assimilative capacity would be consumed between 2039 and beyond 2045, depending upon the scenario. Extrapolation of the projections indicated that the applicable TDS Water Quality Objective would not be exceeded until approximately 2053 to 2070, depending on groundwater quality and the predictive scenario.
Bunker Hill-B Salinity Management Feasibility Study
As Phase 2 was being completed, the Bunker Hill Regional Recycled Water Coalition formed to evaluate the use of recycled water recharge in the Bunker Hill-B Groundwater Management Zone while managing potential impacts from TDS and nitrate.
In response to requirements associated with the Sterling Natural Resource Center recycled water recharge permit, the Coalition commissioned the Bunker Hill Regional Recycled Water Salinity Management Feasibility Study. The Feasibility Study evaluated alternatives for managing salinity associated with recycled water recharge. The Feasibility Study identified that a Regional Desalter may be needed in the future to effectively manage TDS in the Bunker Hill-B Groundwater Management Zone. The study also recommended additional data collection and updated groundwater modeling to inform long-term salinity management strategies and establish appropriate triggers for implementation.
Based on the Feasibility Study, the regional agencies determined that additional technical work should be completed before proceeding with Phase 3. This work is designated as SNMP Phase 3A.
ANALYSIS/DISCUSSION
The proposed SNMP Phase 3A effort will provide the technical analysis needed to determine a long-term salinity management strategy for the Bunker Hill-B Management Zone. The study is intended to support a regional decision on whether to pursue a Subregional Salt and Nutrient Management Plan or advance planning for a Regional Desalter.
Key elements of the Phase 3A effort include:
• Update groundwater modeling using data through 2023 to evaluate current and projected TDS and nitrate conditions.
• Assess the impacts of existing and planned recycled water and recharge projects on groundwater quality, including recharge activities in the Rialto-Colton Cactus Basins.
• Conduct baseline and project-specific modeling scenarios to identify potential changes in TDS and nitrate concentrations over time.
• Prepare technical memoranda and a Phase 3A Report summarizing the modeling results and recommending a regional path forward.
• Coordinate extensively with the SNMP Work Group and Santa Ana Regional Water Quality Control Board regarding modeling assumptions, results, milestones, and long-term use of assimilative capacity.
• Use the Phase 3A findings to establish the scope and direction of subsequent Phase 3B work, including any potential actions related to a Regional Desalter.
• Rialto's participation is limited to a maximum contribution of $29,405. Any increase in Rialto's financial obligation would require the City's prior written approval.
Overall, Phase 3A is a technical and planning effort, not authorization to construct a desalter or other physical facility. The study will provide updated regional groundwater quality information and help participating agencies make an informed decision regarding the most appropriate long-term approach to managing salinity while supporting future water supply, recharge, and recycled water projects. A copy of the SNMP Phase 3A Cost Share Agreement is included as Attachment 1, a copy of the SNMP Phase 3A Cost Share Letter is included as Attachment 2, and the Water Systems Consulting Proposal is included as Attachment 3.
ENVIRONMENTAL IMPACT
The proposed action is not a “Project” as defined by the California Environmental Quality Act (CEQA). Pursuant to Section 15378(a), a “Project” means the whole of an action, which has a potential for resulting in either a direct physical change in the environment, or a reasonably foreseeable indirect physical change in the environment. According to Section 15378(b), a Project does not include: (5) Organizational or administrative activities of governments that will not result in direct or indirect physical changes in the environment.
GENERAL PLAN CONSISTENCY
Approval of the proposed action also complies with the following City of Rialto Guiding Principle 3 in the General Plan.
“Our City government will lead by example, and will operate in an open, transparent, and responsive manner that meets the needs of the citizens and is a good place to do business.”
LEGAL REVIEW
The City Attorney's Office has reviewed the agreement and approved it as to form.
FINANCIAL IMPACTS
Operating Budget Impact
The City's financial obligation under the proposed Cost Sharing Agreement is in the amount not-to-exceed $29,405. Funding is available in FY27 Fund 680 Water Contract Services Account No. 56807960-52011.
Capital Improvement Budget Impact
There is no impact on the Capital Improvement Budget.
Licensing
This action does not require a business license.
ATTACHMENTS
1. SNMP Phase 3A Cost Share Agreement
2. SNMP Phase 3A Cost Share Letter
3. Water Systems Consulting Proposal