Advancing Sustainable Water Management
In 2024, the Sacramento Regional Water Bank (Water Bank) team continued to make progress on key documents essential to advancing sustainable water management in the Sacramento region. Efforts focused on developing frameworks such as the Water Accounting System (WAS), the Programmatic Environmental Impact Report (PEIR), and scientific groundwater modeling, all crucial to achieving the Water Bank’s sustainability goals and supporting its operations. Development of the Water Bank is now at the halfway mark of the projected three-year timeline.
Water Accounting System
Significant progress was made in 2024 on the nearly complete Water Accounting System (WAS), a crucial tool for managing and tracking water movement within the Water Bank to support basin sustainability. The WAS will enable water managers to monitor water deposited into underground aquifers, withdrawals, and natural storage losses. Additionally, the system will account for water intentionally left behind to support the long-term health and sustainability of the groundwater basin.
The WAS will be implemented across the North and South American Subbasins, where the Water Bank operates. It will include a detailed set of principles, procedures, and tools designed to support effective and sustainable Water Banking activities.
Key components of the WAS include:
- Operational baseline: The Water Bank’s starting water balance.
- Recharge accounting: Tracking water deposited into the basin.
- Recovery accounting: Monitoring groundwater withdrawals to meet needs.
- Leave-behind: Directly supports sustainability by allocating water to maintain environmental and system health.
- Loss tracking: Determined by scientific methods and accounted for in the calculation of water available for recovery.
- Storage rights tracking: Documenting surface water rights and contract water used in the bank.
- In-lieu recovery tracking: Tracking surface water supplies that are not used (forgone) when agencies deliver banked groundwater to customers instead of surface water.
Looking Ahead: The Water Bank team plans to host a fourth Stakeholder Forum to present the WAS to the public on February 4, 2025.
Environmental Review Process
In compliance with the California Environmental Quality Act (CEQA), the RWA is developing a Programmatic Environmental Impact Report (PEIR) to assess the Water Bank’s broad environmental effects. The PEIR allows for streamlined, future project-specific reviews as needed.
The environmental review process for the Water Bank continued in 2024, with key updates to the Project Description and a reissued Notice of Preparation (NOP). The 2024 NOP revision added out-of-basin transfers of up to 35,000 acre-feet per year. The consulting team incorporated public comments into a revised scoping report.
Modeling efforts in support of the PEIR also advanced in 2024. The PEIR will analyze current water operations compared with those proposed by the Water Bank. The consulting team updated municipal and industrial demands based on 2020 Urban Water Management Plans and developed validated baseline models that capture both current conditions and preliminary Water Bank projections.
Looking ahead: The consulting team will refine their approach to estimating banking losses, incorporating feedback from the Project Committee and Groundwater Sustainability Agencies (GSAs). The Draft PEIR is expected to be released before the third quarter of 2025. Additionally, RWA will seek federal recognition of the Project as an approved facility for banking Central Valley Project (CVP) water under the National Environmental Policy Act (NEPA).
Groundwater Modeling
Accurate groundwater modeling is essential to the Water Bank’s success, providing the scientific foundation for sustainably managing the Sacramento region’s water resources. The region’s modeling approach is among the most advanced in California, combining the state’s CalSim 3 surface water model with the locally developed CoSANA groundwater model to examine interactions between surface and groundwater systems.
The CalSim 3 model, from the California Department of Water Resources, provides broad-scale data on water operations across projects like the Central Valley Project, State Water Project, and Delta. CoSANA, created by the region’s Groundwater Sustainability Agencies (GSAs), focuses on the Sacramento area’s groundwater, providing a highly accurate, real-world view of basin conditions. Years of local monitoring, updates, and investment have refined CoSANA to align closely with observed basin behavior.
To prepare for analyzing Water Bank operations under the WAS and to support environmental review, the Water Bank team conducted a Water Management Operations Pilot this year to analyze various conjunctive use and water banking scenarios. They also aligned CoSANA’s local groundwater data with CalSim’s surface water data to create the framework necessary for simulating Water Bank activities under different conditions using the most accurate data.
Looking Ahead: The team will model Water Bank operations based on the WAS under various climate and management scenarios. These simulations will assess the potential impacts and sustainability benefits of the Water Bank.
Community Outreach and Engagement
The Water Bank outreach program spotlighted in-lieu recharge through new educational materials and a video explaining this critical groundwater replenishment process, which has supported the Sacramento region for over two decades.
A new video, In-lieu Recharge: Enhancing Nature’s Rainy Day Fund, is featured on the Water Bank website and in both the California Water Plan eNews and at the Association of California Water Agencies Conference.
Additionally, the Water Bank team continued its Q&A Connect series, exploring topics such as how the Water Bank will address groundwater challenges under the Sustainable Groundwater Management Act, its relationship to programs like Flood MAR and Watershed FIRO MAR, connections to the Harvest Water project, and the role of “leave behind” and “loss” in sustainable management practices.
Spanish-language resources were also added to the Water Bank website, expanding accessibility to community members.
Looking Ahead: The outreach program will continue supporting the environmental review process and further public engagement in 2025 through ongoing Q&A Connect features and updated resources. The Water Bank team looks forward to providing more updates during the fourth public Stakeholder Forum on February 4, 2025. To receive Water Bank updates and notifications, please sign up at https://sacwaterbank.com/contact-us/.