Managed Environmental Water Use Efficiency: Evidence in Practice

University of California, Berkeley (UC Berkeley) | May 12th, 2006

The California Water Plan Update 2005 first introduced the term Managed Environmental Water Use Efficiency (MEWUE). Specifically, it defines MEWUE as a “mechanism to an

The California Water Plan Update 2005 first introduced the term Managed Environmental Water Use Efficiency (MEWUE). Specifically, it defines MEWUE as a “mechanism to analyze alternative uses of managed environmental water to determine which allocation of a given amount of water will maximize environmental benefits, and as a means to improve decision-making over time.” While MEWUE is a new term, we found several instances where managers maximized environmental benefit from a given amount of water in current practice. This paper demonstrates and analyzes current applications of MEWUE. It then provides the Department of Water Resources with the following recommendations to advance the concept and formally incorporate it into environmental water management: Formalize a MEWUE Policy to clearly state that the goal of MEWUE is a management strategy to maximize environmental benefit and not a water conservation policy. Develop Best Management Practices to increase understanding, provide guidance, and encourage use of MEWUE. Operate a MEWUE Pilot to learn more about the way MEWUE works, understand its strengths, and improve on its weaknesses. Facilitate an Environmental Water Market by applying experience and infrastructure to provide solutions for projects that require more water.

Managed winter flooding of alfalfa recharges groundwater with minimal crop damage

California Agriculture (UCANR) | January 16th, 2018

It is well known that California experiences dramatic swings in precipitation that are difficult to predict and challenging to agriculture. In times of drought, groundwat

It is well known that California experiences dramatic swings in precipitation that are difficult to predict and challenging to agriculture. In times of drought, groundwater serves as a crucial savings account that is heavily relied upon. However, few tools exist to proactively refill this crucial reserve in wet years. We explored the idea of intentional winter flooding of agricultural land to promote on-farm recharge of the underlying groundwater. Field experiments were conducted on two established alfalfa stands to determine the feasibility of groundwater recharge and test realistic water application amounts and timings and potential crop damage. We studied soils with relatively high percolation rates and found that most of the applied water percolated to the groundwater table, resulting in short-lived saturated conditions in the root zone and minimal yield loss. While caution is appropriate to prevent crop injury, winter recharge in alfalfa fields with highly permeable soils appears to be a viable practice.

Management of Brine Discharges to Coastal Waters: Recommendations of a Science Advisory Panel

Southern California Coastal Water Research Project | June 6th, 2012

A panel of five experts in diverse fields related to brine disposal in the ocean was convened to advise the State Water Resources Control Board on best practices for brin

A panel of five experts in diverse fields related to brine disposal in the ocean was convened to advise the State Water Resources Control Board on best practices for brine disposal in support of the development of an amendment to the Ocean Plan. The brine concentrates can result from desalination of brackish groundwater, recycling domestic wastewater, and especially desalination of seawater. The potential of seawater desalination to provide potable water in the state is growing rapidly, with many plants currently proposed or in the planning stage. The state presently has no regulations on brine discharges and each plant is considered on a case-by-case basis. The panel reviewed extensive material, including peer-reviewed journal articles, articles in the gray literature, NPDES permits that have been issued, various regulations from around the world, and results of monitoring studies, and heard presentations about experience with operating discharges. From these reviews it is apparent that concentrate can be disposed of with minimal environmental effects if properly executed. Desirable methods of discharge include co-disposal with heated cooling water from power plants or domestic wastewater, or from a multiport diffuser if “pure” brine is released. Discharges with rapid initial dilution into areas of good flushing result in impacts that extend only a few tens of meters from the discharge. Conversely, poorly implemented disposal schemes with low initial dilution in poorly flushed areas can cause widespread alterations of community structure in seagrass, coral reef, and soft-sediment systems.

Management of the Colorado River: Water Allocations, Drought, and the Federal Role

Congressional Research Service (CRS) | August 4th, 2022

Management of the Colorado River: Water Allocations, Drought, and the Federal Role

Congressional Research Service (CRS) | April 4th, 2024

From its headwaters in Colorado and Wyoming to its terminus in the Gulf of California, the Colorado River Basin covers more than 246,000 square miles. The basin spans sev

From its headwaters in Colorado and Wyoming to its terminus in the Gulf of California, the Colorado River Basin covers more than 246,000 square miles. The basin spans seven U.S. states (Wyoming, Colorado, Utah, New Mexico, Arizona, Nevada, and California) and two countries (the United States and Mexico). Pursuant to federal law, the Bureau of Reclamation (Reclamation), a component of the Department of the Interior (DOI), plays a prominent role in the management of the basin’s waters. In the Lower Basin (i.e., Arizona, Nevada, and California), Reclamation also serves as water master on behalf of the Secretary of the Interior, a role that elevates the status of the federal government in basin water management. The federal role in managing Colorado River water is magnified by the multiple federally owned and operated water storage and conveyance facilities in the basin, which provide low-cost water and hydropower supplies.

Management of the Colorado River: Water Allocations, Drought, and the Federal Role

Congressional Research Service (CRS) | September 7th, 2022

Managing a cyanobacteria harmful algae bloom “hotspot” in the Sacramento – San Joaquin Delta, California

Journal of Environmental Management (Elsevier) | December 10th, 2023

Managing Agricultural Irrigation Drainage Water: A guide for developing Integrated On-Farm Drainage Management systems

California State Water Resources Control Board (SWRCB) | May 6th, 2004

Chronic problems of salt, selenium, boron and other naturally occurring elements in surface and groundwater supplies plague agricultural regions throughout the Westside o

Chronic problems of salt, selenium, boron and other naturally occurring elements in surface and groundwater supplies plague agricultural regions throughout the Westside of the San Joaquin Valley and the western U.S. Compounding the problem is the build-up of salty subsurface groundwater resulting from dense clay layers and inadequate natural drainage. The Integrated On-Farm Drainage Management (IFDM) system was developed to manage these problems. A state-of-the-art, yet practical irrigation management system, the IFDM provides for drainage water reuse to improve water availability for crop production and to minimize salt and selenium risks to water quality and the environment. IFDM manages irrigation water on salt sensitive, high value crops and reuses drainage water to irrigate salt-tolerant crops, trees and halophyte plants. Salt and selenium are removed from the farming system and can be marketed. This system views the subsurface drainage water containing salts and selenium as resources, rather than considering them as wastes and environmental problems.

Managing An Uncertain Future: Climate Change Adaptation Strategies for California’s Water

California Department of Water Resources (DWR) | December 12th, 2008

For California water managers, the future is now. Climate change is already having a profound impact on water resources as evidenced by changes in snowpack, river flows a

For California water managers, the future is now. Climate change is already having a profound impact on water resources as evidenced by changes in snowpack, river flows and sea levels. The Department of Water Resources (DWR) will continue to play a leadership role in adapting to these changes. DWR is already engaged in a number of efforts designed to improve California’s ability to cope with a changing climate. However, more must be done. This report recommends a series of adaptation strategies for state and local water managers to improve their capacity to handle change. Many of the strategies will also help adapt our water resources to accommodate non-climate demands including a growing population, ecosystem restoration and greater flood protection. Several of the recommendations in this report are ready for immediate adoption, while others need additional public deliberation and development. Some can be implemented using existing resources and authority, while the majority will require new resources, sustained financial investment and significant collaborative effort. Many of California’s most important water resource investments remain dependent on bond funding approved by voters. As a result, they are well funded in some years, but underfunded in most. This history of uneven and irregular investment has delayed progress in areas that have the potential to yield substantial gains over short periods of time. DWR presents this report as part of the process of updating the California Water Plan, and as part of the California Resources Agency’s draft statewide Climate Adaptation Plan. Overall, this report urges a new approach to managing California’s water and other natural resources in the face of a changing climate.

Managing California’s Freshwater Ecosystems: Lessons from the 2012-16 Drought

Public Policy Institute of California (PPIC) | November 16th, 2017

The 2012–16 drought caused unprecedented stress to California’s ecosystems and pushed many native species to the brink of extinction. It also tested the laws, policie

The 2012–16 drought caused unprecedented stress to California’s ecosystems and pushed many native species to the brink of extinction. It also tested the laws, policies, and institutions charged with protecting the environment. Eight case studies on environmental water management during the drought reveal both strengths and weaknesses in federal, state, and local response that can inform how California addresses future droughts. Three areas of reform hold promise for improving ecosystem conditions and reducing conflict: * Improve water accounting. Drought management requires accurate and timely information about water use and availability and about likely environmental response to changes in water supply. But California’s current tracking systems are neither timely nor transparent. To address these gaps, environmental water accounting and ecosystem monitoring systems need an overhaul. * Prepare for drought. With a few significant exceptions, environmental water managers were unprepared for the environmental consequences of an extended drought, and were forced to make ad hoc decisions during a crisis. Developing watershed-level plans that set ecosystem priorities and identify trade-offs would help managers anticipate drought and drive implementation of habitat investments and water allocation. Annual watering plans that guide management under different types of water years would better engage and inform water users. * Develop ecosystem water budgets. Current methods of allocating water to support ecosystem health rely on minimum flow standards that are unevenly enforced and often insufficient during drought. Ecosystem water budgets, which allocate a portion of water to the ecosystem within watersheds, could enable more flexible and effective water management during dry times. Although state and federal agencies have important