Water Resources Systems Planning and Management: An Introduction to Methods, Models and Applications

United Nations (UN) | January 1st, 2017

Throughout history, much of the world has witnessed ever-greater demands for reliable, high-quality and inexpensive water supplies for domestic consumption, agriculture,

Throughout history, much of the world has witnessed ever-greater demands for reliable, high-quality and inexpensive water supplies for domestic consumption, agriculture, and industry. In recent decades there have also been increasing demands for hydrological regimes that support healthy and diverse ecosystems, provide for water-based recreational activities, reduce if not prevent floods and droughts, and in some cases, provide for the production of hydropower and ensure water levels adequate for ship navigation. Water managers are challenged to meet these multiple and often conflicting demands. At the same time, public stakeholder interest groups have shown an increasing desire to take part in the water resources development and management decision-making process. Added to all these management challenges are the uncertainties of natural water supplies and demands due to changes in our climate, changes in people's standards of living, changes in watershed land uses and changes in technology. How can managers develop, or redevelop and restore, and then manage water resources systems - systems ranging from small watersheds to those encompassing large river basins and coastal zones - in a way that meets society's changing objectives and goals? In other words, how can water resources systems become more integrated and sustainable?

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

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

Water systems in California: Ownership, geography, and affordability

Utilities Policy (Elsevier) | August 10th, 2021

This study asks whether different types of water systems serve different types of communities and differ with respect to affordability. Using 2017 data for California we

This study asks whether different types of water systems serve different types of communities and differ with respect to affordability. Using 2017 data for California we match service area boundaries with census income data and rate structures to compare the geography, income distribution and affordability of water rates within communities served by systems of different ownership types. We find that for-profit and publicly owned systems serve communities of similar income distributions, while not-for-profit mutual water companies serve higher-income communities. Regulated privately-owned systems charge more for water while providing more low-income assistance and shutting off fewer households than publicly owned systems.

Water transfers (Resource Management Strategy)

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

The California Water Code (CWC) defines a water transfer as a temporary or long-term change in the point of diversion, place of use, or purpose of use due to a transfer,

The California Water Code (CWC) defines a water transfer as a temporary or long-term change in the point of diversion, place of use, or purpose of use due to a transfer, sale, lease, or exchange of water or water rights. Temporary water transfers have a duration of one year or less (CWC Section 1725). Long-term water transfers have a duration of more than one year (CWC Section 1728). Transfers can be between water districts that are neighboring or across the state, provided there is a means to convey or store the water. A water transfer can be a temporary or permanent sale of water or a water right by the water right holder, a lease of the right to use water from the water right holder, or a sale or lease of a contractual right to water supply. Water transfers can also take the form of long-term contracts for the purpose of improving long-term supply reliability.

Water Transfers Brochure: Guidance and Information for Water Transfers

U.S. Bureau of Reclamation (USBR) | February 13th, 2014

The Bureau of Reclamation (Reclamation) developed the Water Transfers Brochure (Brochure) to assist water purveyors in the preparation of water transfer and Warren Act pr

The Bureau of Reclamation (Reclamation) developed the Water Transfers Brochure (Brochure) to assist water purveyors in the preparation of water transfer and Warren Act proposals and documents. It is a “work in progress” that will be refined as necessary to adapt to changing circumstances or improve its utility, this Brochure provides general guidance on communicating, preparing, and submitting a proposal, as well as presenting estimated timelines for associated requirements, actions, and approvals. This Brochure is meant to increase the efficiency of the logistical and administrative processes that Reclamation and the transfer parties control and to further the goal of timely facilitation of water transfers that require conveyance through Central Valley Project (CVP) facilities or otherwise require Reclamation approval. This Brochure provides a framework and certain details of the processes; however, dependent on the transfer or Warren Act proposal, additional coordination or steps may be necessary to facilitate approval of a proposed action. Reclamation encourages all water purveyors to work closely with their designated Reclamation representative in developing transfer, exchange, and/or Warren Act proposals.

Water Year 2021 Compound Precipitation and Temperature Extremes in California and Nevada

American Meteorological Society (AMS) | December 23rd, 2022

The most intense 22-yr drought in the western United States since 800 CE (Williams et al. 2022) was extended by compound dry and hot extremes in Water Year 2021 (October

The most intense 22-yr drought in the western United States since 800 CE (Williams et al. 2022) was extended by compound dry and hot extremes in Water Year 2021 (October 2020–September 2021). Compared to an instrumental record that dates to 1895, low precipitation (Fig. 1a) and high temperatures (Fig. 1b) were widespread across the western United States. The intense and prevalent drought has caused water delivery shortages (U.S. Bureau of Reclamation 2021), damaged ecosystems (Wlostowski et al. 2022), and contributed to extreme wildfires (e.g., Fu et al. 2021; Gutierrez et al. 2021; Abolafia-Rosenzweig et al. 2022). California and Nevada (CA–NV) were once again at the epicenter of drought and heat in Water Year 2021 (California Department of Water Resources 2021). This was the first time since 1895 that precipitation fell below –1.5 standardized departures and temperatures exceeded 1.5 standardized departures concurrently for the two-state average (Fig. 1c). Precipitation and temperatures were individually extreme as well, as the former was the second lowest since 1895 and the latter was the second highest. We examine whether the co-occurrence of anthropogenic climate change and La Niña, two principal climate drivers during Water Year 2021, altered the risk of unprecedented compound dry and hot extremes in CA–NV during Water Year 2021. Our assessment investigates the factors related to compound extremes that lead to heightened societal impacts compared to individual extreme events (e.g., AghaKouchak et al. 2020; Zscheischler et al. 2020; W. Zhang et al. 2021).

Water Year 2023: Weather Whiplash, from Drought to Deluge

California Department of Water Resources (DWR) | October 4th, 2023

Water Year 2023 demonstrated California’s high climate variability, ending the state’s driest consecutive three-year period with one of the snowiest years of record.

Water Year 2023 demonstrated California’s high climate variability, ending the state’s driest consecutive three-year period with one of the snowiest years of record. Even though California has been experiencing a theme of aridity in the 21st century (the statewide droughts of 2007-2009, 2012-2019, and 2020-2022), Water Year 2017 was the state’s second wettest in terms of statewide precipitation. Climate change is expected to amplify naturally occurring variability in the long term, potentially result in a shorter wet season for California but one with more extreme atmospheric river storms and hence potentially greater flood damage risk.