Water Special Districts: A Look at Governance and Public Participation

Legislative Analyst's Office (LAO) | March 15th, 2002

Chapter 107, Statutes of 2001 (AB 38, Strom-Martin), requires the Legislative Analyst’s Office to undertake a study of these special districts. In this review we find t

Chapter 107, Statutes of 2001 (AB 38, Strom-Martin), requires the Legislative Analyst’s Office to undertake a study of these special districts. In this review we find that while some individual districts have pursued controversial policies, there is no evidence of a statewide structural governance problem.

Water storage decisions will determine the distribution and persistence of imperiled river fishes

Ecological Society of America (Wiley) | December 17th, 2020

Managing the world’s freshwater supply to meet societal and environmental needs in a changing climate is one of the biggest challenges for the 21st century. Dams provid

Managing the world’s freshwater supply to meet societal and environmental needs in a changing climate is one of the biggest challenges for the 21st century. Dams provide water security; however, the allocation of dwindling water supply among reservoirs could exacerbate or ameliorate the effects of climate change on aquatic communities. Here, we show that the relative sensitivity of river thermal regimes to direct impacts of climate change and societal decisions concerning water storage vary substantially throughout a river basin. In the absence of interspecific interactions, future Colorado River temperatures would appear to benefit both endemic and nonnative fish species. However, endemic species are already declining or extirpated in locations where their ranges overlap with warmwater nonnatives and changes in water storage may lead to warming in some of the coolest portions of the river basin, facilitating further nonnative expansion. Integrating environmental considerations into ongoing water storage negotiations may lead to better resource outcomes than mitigating nonnative species impacts after the fact.

Water Storage Issue Paper

Delta Stewardship Council (Delta Council) | April 8th, 2013

This Issue Paper, authored by DSC Vice-Chair Randy Fiorini, is entitled, “Don’t Just Think ‘Big’ When Adding to State’s Water Storage Capacity.”  The paper d

This Issue Paper, authored by DSC Vice-Chair Randy Fiorini, is entitled, “Don’t Just Think ‘Big’ When Adding to State’s Water Storage Capacity.”  The paper discusses the successes of many local public water agencies in constructing small storage projects, and suggests the State consider small, as well as large scale storage projects, to address California’s water storage needs. Specific recommendations include: The California Water Commission should conduct a statewide survey of public water agencies to determine locations that have been considered locally or regionally for water storage but have not been pursued. To ensure public water agency participation the California Water Commission should partner with the Association of California Water Agencies to prepare for and conduct the survey and produce and inventory list. Once a statewide survey of possible storage locations is complete and a comprehensive list of locations has been identified, the Department of Water Resources and the California Water Commission should evaluate and identify which locations with local support have a public benefit.

Water Stress and a Changing San Joaquin Valley

Public Policy Institute of California (PPIC) | March 1st, 2017

The San Joaquin Valley—California’s largest agricultural region, and an important contributor to the nation’s food supply—is in a time of great change and growing

The San Joaquin Valley—California’s largest agricultural region, and an important contributor to the nation’s food supply—is in a time of great change and growing water stress. Agriculture is a leading economic driver and the predominant water user. The region’s farms and related manufacturing businesses account for 25 percent of the valley’s revenues and 16 percent of local jobs—and 89 percent of annual net water use. The latest drought underscored valley agriculture’s vulnerability to water scarcity and long-term declines in groundwater reserves. The region has a greater abundance of productive farmland than local water supplies for irrigation. In most years since the mid-1980s, groundwater has been used faster than it is being replenished (“groundwater overdraft”). Over the past three decades, overdraft has averaged nearly 2 million acre-feet per year, or 13 percent of net water use. This has contributed to increased pumping costs, dry wells, sinking lands, and declining reliability of this vital drought reserve.

Water Supply and Habitat Resiliency for a Future Los Angeles River: Site-Specific Natural Enhancement Opportunities Informed by River Flow and Watershed-Wide Action

Nature Conservancy | December 15th, 2016

The mission of The Nature Conservancy is to conserve the lands and waters on which all life depends. As the Conservancy engages with the Los Angeles region, they are inve

The mission of The Nature Conservancy is to conserve the lands and waters on which all life depends. As the Conservancy engages with the Los Angeles region, they are investigating what it means to carry out this mission in the highly urbanized Los Angeles River ecosystem. As a starting point, it is known that the basic ecological principles of science apply to all environmental systems, regardless of their location. Therefore, the Conservancy is testing these principles by applying them in the Elysian Valley of the Los Angeles River and identifying habitat enhancement requirements, opportunities, and constraints. As a basic principle of ecological systems, a watershed’s hydrology determines the flow characteristics of its river system. These flows define what the biological characteristics of that river will be, which in turn determine what kinds of habitat enhancement projects will succeed at various locations along a river. The study of the Elysian Valley included one full year of multi-taxa biological surveys, a historical ecology investigation of the Elysian Valley, and a review of historic and existing hydrological and hydraulic conditions. Major findings of this study are: Multiple Flow Scenarios = Uncertainty: There are currently multiple visions for the flow characteristics of the Los Angeles River as a whole due to differing management priorities of the agencies and stakeholders that have governance over different aspects of this hydrologic system. Bringing the various hydrologic plans and possibilities for the watershed into a single integrated vision of system flow characteristics will allow certainty and clarity at the site level for the design of habitat projects anywhere in the River system, including the Conservancy’s study area. Flows Drive Biology: The study area currently has higher flood and much higher dry weather flow rates than its historic condition. These high flow rates are supporting and encouraging non-native and invasive species. This leads to a lower level of biological diversity and resiliency than what would exist under lower flow rates, particularly during dry weather conditions. Prioritize Complementary Habitats: Enhancing and increasing the amount of perennial riparian habitat in-stream alone will not create as much biological value as identifying complementary enhancement opportunities outside of the River channel in adjacent upper terrace floodplain and upland habitats (e.g. alluvial scrub, mulefat scrub, willow scrub, oak-sycamore woodland, sage scrub, and grassland). River Adjacent Land Use: Land uses adjacent to the River and throughout the watershed are a part of the solution and part of the Los Angeles River’s biological and hydrologic system. The landscaping and hydrology of these areas should be designed to provide a value-added role to the habitat functions of the Los Angeles River ecosystem. Next steps for advancing the discussion of habitat enhancement include working with local stakeholders and agencies to find consensus on a flow condition for the River and its Watershed as a whole. In the study area itself there are six complementary project opportunities that could be implemented in the near term to advance understanding of habitat enhancement for the Los Angeles River. These smaller, localized projects can be used as pilot projects for the complicated jurisdictional and regulatory processes that all future habitat projects will have to navigate. They will provide a manageable and controlled process that will bring the necessary agencies together to identify the most effective processes for future projects throughout the Los Angeles River ecosystem.

Water Supply Conditions in Southern California during 1958-1959, Volume II, Water Level Data, Central Coastal and Los Angeles Regions

California Department of Water Resources (DWR) | May 1st, 1961

Water Supply Damage, Recovery, and Lifeline Interaction in an Earthquake Sequence

American Society of Civil Engineers (ASCE) | September 7th, 2017

Earthquake damage to water supply systems profoundly affects society, potentially costing the economy tens of billions of dollars. Water agencies for 22% of the U.S. popu

Earthquake damage to water supply systems profoundly affects society, potentially costing the economy tens of billions of dollars. Water agencies for 22% of the U.S. population face high seismic risks. Computer models can help operators manage that risk. In recent research, the University of Colorado (CU) developed a stochastic model of water-supply pipeline damage and restoration. It offers some new capabilities: time-varying repair resources, multiple earthquake perils, lifeline interaction, avoiding hydraulic analysis, and no black-box software. CU exercised the model for the East Bay Municipal Utility District (EBMUD) and the San Jose Water Company, considering a hypothetical large Hayward Fault earthquake. EBMUD staff peer reviewed the methodology and results and find them credible and consistent with past earthquakes. EBMUD is using the results as part of its resilience program. Possible uses include prioritizing additional hardening or redundancy, identifying repair priorities, estimating resource needs, and informing earthquake exercises.

Water Supply Forecasting

U.S. Department of Agriculture (USDA) | March 9th, 2011

Chapter 7: Part 622 Snow Survey and Water Supply Forecasting from the National Engineering Handbook The U.S. Department of Agriculture (USDA) Natural Resources Conser

Chapter 7: Part 622 Snow Survey and Water Supply Forecasting from the National Engineering Handbook The U.S. Department of Agriculture (USDA) Natural Resources Conservation Service (NRCS) Snow Survey and Water Supply Forecasting Program issues water supply forecasts for hundreds of points in the Western United States. The primary forecast product is a seasonal volume for a specified period of months (e.g., April–July). These forecasts are issued near the first of the month between January and June. Mid-month updates are also issued for selected forecast points. In addition, daily guidance forecasts are issued for a subset of forecast points using an automated procedure. This chapter describes the essential features of water supply forecasting as practiced in the NRCS. The topics are presented in a roughly chronological sequence of activities, from forecasting point establishment, to data gathering, to model development, to operations, and finally to verification. Citations of foundational professional literature and NRCS technical notes are given to provide sources of details on mathematical procedures and other technical information not explicitly described in this chapter.

Water Supply in the Conterminous United States, Alaska, Hawaii, and Puerto Rico, Water Years 2010–20, Chapter B of U.S. Geological Survey Integrated Water Availability Assessment—2010–20

U.S. Geological Survey (USGS) | January 17th, 2025

The following are the key points of this chapter: Throughout much of the Great Plains and Northeast through Midwest aggregated hydrologic regions, low precipitation

The following are the key points of this chapter: Throughout much of the Great Plains and Northeast through Midwest aggregated hydrologic regions, low precipitation totals in water years 2011 and 2012 resulted in low streamflow, evapotranspiration, and soil moisture, associated with one of the most substantial droughts since the 1930s. The highest interannual variability in precipitation was in the California–Nevada, Texas, Southern High Plains, and Southwest Desert hydrologic regions, whereas the lowest interannual variability was in the Florida, Tennessee–Missouri, and Northeast hydrologic regions. Among the Western aggregated hydrologic region, where snow is critical for water availability, the California–Nevada hydrologic region had the highest interannual variability in maximum snow accumulation with a coefficient of variation (CV) of 0.60, whereas the Columbia–Snake, Pacific Northwest, and Central Rockies hydrologic regions all had a CV of less than 0.36. Six of 29 unconfined and 6 of 23 confined principal and regional aquifer systems had current water-level percentiles (median 2010–20) of less than 30 percent of historical water levels (that is, median 2000–20 water levels) including the California Coastal Basin aquifers, the Colorado Plateaus aquifers, and the Central and Southern regions of the High Plains aquifer. Hydrologic regions with low precipitation and little storage coincide with aquifer systems that have shown a decline in groundwater levels during water years 2010–20, including the Southern High Plains, Central High Plains, and Texas hydrologic regions. Companion chapters: U.S. Geological Survey Integrated Water Availability Assessment—2010–20, Chapter A Status of Water-Quality Conditions in the United States, 2010–20, Chapter C  Water Use Across the Conterminous United States, Water Years 2010–20, Chapter D  Climate Change and Future Water Availability in the United States, Chapter E  Integrated Water Availability in the Conterminous United States, 2010–20, Chapter F 

Water Surplus and Drought Management Update - Conditions as of 11/29/2022

Metropolitan Water District of Southern California (MWD) | December 13th, 2022