System Reoperation (Resource Management Strategy)

California Department of Water Resources (DWR) | July 29th, 2016

System reoperation in the context of water resources means changing existing operation and management procedures for a water resources system consisting of supply and con

System reoperation in the context of water resources means changing existing operation and management procedures for a water resources system consisting of supply and conveyance facilities and end user demands with the goal of increasing desired benefits from the system. System reoperation may seek to improve existing water facilities to meet existing system needs more efficiently and reliably, or it may seek to prioritize one system need over another. Although reoperation of existing facilities is generally regarded as the preferred alternative to constructing major new facilities, minor physical modifications to existing facilities may be necessary to eliminate constraints to reoperation and to meet operational goals. Changes to the water rights or regulatory framework for allocating water — for example, modifying existing water rights or creating new supply exchange agreements — may also be required. Some systems may be very simple and include only a single surface water reservoir or groundwater basin. Other water systems may be much more complex, consisting of many facilities that form a combination of local, interregional, and interstate water sources and delivery destinations. The concept “system reoperation” applies to the system at all scales, thus reoperation can be implemented at different scales within a system, ranging from individual facilities to several integrated components.

Systems Analysis and Optimization of Local Water Supplies in Los Angeles

American Society of Civil Engineers (ASCE) | September 1st, 2017

Los Angeles, which relies on large infrastructure systems that import water over hundreds of miles, faces a future of reduced imports. Within Los Angeles and its hund

Los Angeles, which relies on large infrastructure systems that import water over hundreds of miles, faces a future of reduced imports. Within Los Angeles and its hundreds of water agencies, the capacity to adapt to future changes is influenced by laws, institutions, and hydrogeology. This paper presents a systems analysis of urban water management in metropolitan Los Angeles County to assess opportunities for increasing local water reliance. A network flow model was developed to investigate management tradeoffs across engineered, social, and environmental systems. With an aggressive regional demand target, increased stormwater capture (300%), and prioritized water reuse from existing facilities, imported water supplies can be cut by 30% while maintaining landscapes, economic productivity, and groundwater resources. Further reducing imports (by 40–50%) is possible through actions to promote additional reuse, recharge, conservation, and groundwater access. Reducing imported water without significant conservation results in likely groundwater overdraft. Fragmented networks of agencies in Los Angeles create an uneven landscape of vulnerability to water shortages. The paper discusses model applications, research needs, and policy implications of results for dry-climate cities.

Tahoe: State of the Lake Report 2025

University of California, Davis (UC Davis) | July 18th, 2025

UC Davis has conducted research at Lake Tahoe since 1950, and scientists from UC Davis Tahoe Environmental Research Center have been monitoring conditions at the lake con

UC Davis has conducted research at Lake Tahoe since 1950, and scientists from UC Davis Tahoe Environmental Research Center have been monitoring conditions at the lake continuously since 1968. This has created a unique document of change for one of the world’s most iconic and vulnerable lakes.

Tap Water Affordability in Arizona

Arizona State University (ASU) | February 20th, 2025

In this report, the Kyl Center for Water Policy presents a comprehensive set of tap water affordability data for community water systems (CWS) in Arizona. Communities can

In this report, the Kyl Center for Water Policy presents a comprehensive set of tap water affordability data for community water systems (CWS) in Arizona. Communities can use this study to better assess how their current and future charges for water impact low- and median-income households. Water access can be improved when water charges are designed with affordability in mind so that fewer families face the risk of disconnection due to non-payment. On the other hand, most water providers rely on fees to pay for replacing aging infrastructure and water system improvements to ensure reliability.

Technical Guidance for Incorporating Climate Change Information into Water Resources Planning Studies

U.S. Bureau of Reclamation (USBR) | ?

The impacts of climate change are being felt across the Western United States. Warming is affecting water supplies by changing the overall annual volume of precipitation

The impacts of climate change are being felt across the Western United States. Warming is affecting water supplies by changing the overall annual volume of precipitation and altering the balance of rain versus snowfall. Communities are facing increasing problems with water availability and drought, flooding, and increased risk of forest fires. The requirements established by Secretarial Order 3289, Departmental Manual 523 DM 1, Executive Order 13653, and Reclamation’s Directives and Standards CMP 09-02 for feasibility studies reinforces the need for Reclamation's on-going programs to be more resilient to the impacts of climate change and for continued efforts to incorporate climate change information into aspects of our mission where it has not been fully considered in the past such as in decisions regarding ecosystem restoration, reservoir operations, infrastructure investments and planning capacity. This document is an important step to reinforcing Reclamation’s planning capacity by providing guidance to help study teams navigate the range of planning and technical methods available to account for climate change impacts in feasibility studies. The effects of climate change have altered and will continue to alter the basic assumptions underlying Reclamation’s water resources planning. Effective water management and planning rely on an understanding of climate change impacts on water supply, demand, and criteria that govern or guide water management. The guidance in this document may also be applied to environmental compliance studies since they are typically conducted concurrently with feasibility studies. The guidance is organized around the planning and technical framework for conducting a feasibility study as detailed in CMP 09-02, and which occurs in two phases: the scoping phase and the alternative formulation and evaluation phase.

Temescal Basin Groundwater Sustainability Plan

Temescal Basin Groundwater Sustainability Agency | January 27th, 2022

Wishing to provide a framework for cooperative groundwater management and SGMA compliance, the City of Corona (Corona), City of Norco (Norco), and the Home Gardens Coun

Wishing to provide a framework for cooperative groundwater management and SGMA compliance, the City of Corona (Corona), City of Norco (Norco), and the Home Gardens County Water District (HGCWD) executed a Memorandum of Understanding (MOU) in March 2017 establishing the Temescal Basin Groundwater Sustainability Agency (Temescal GSA). In August 2017, the Temescal GSA became the GSA for the Basin by submitting a formation notice to DWR. While Corona is leading this effort, the GSP will be developed jointly among the three agencies, with coordinated implementation toward sustainable management. Due to size, the file has been divided into four parts. Part 1, Part 2, Part 3, Part 4

Temporary Restraining Order in Kings County Farm Bureau et al v. California State Water Resources Control Board

Superior Court of California, County of Kings | July 11th, 2024

Tentative Ruling, Friant Water Authority vs. Eastern Tule Groundwater Sustainability Agency

Superior Court of California, County of Tulare | June 25th, 2024

The 1991 Drought Water Bank

California Department of Water Resources (DWR) | January 1st, 1991

This report, produced by the Department of Water Resources, provides a retrospective of the operations of the 1991 Drought Water Bank.

This report, produced by the Department of Water Resources, provides a retrospective of the operations of the 1991 Drought Water Bank.

The 2025-26 Budget: Proposition 4 Spending Plan

Legislative Analyst's Office (LAO) | February 12th, 2025