Water Ages Explain Tradeoffs Between Long-Term Evapotranspiration and Ecosystem Drought Resilience

American Geophysical Union (AGU) | May 23rd, 2023

Water Allocation in California - Legal Rights and Reform Needs

Golden Gate University (GSU) | March 31st, 1982

FOREWARD: Water supply, allocation, use and conservation are constantly debated in California, often appearing as highly charged political issues in candidates' races and

FOREWARD: Water supply, allocation, use and conservation are constantly debated in California, often appearing as highly charged political issues in candidates' races and on election ballots. This year is no exception, with major ballot propositions already scheduled for the June primary election and being circulated to qualify for the November general election. Accordingly this Research Paper on legal aspects of water allocation is being published for the valuable background it affords readers wishing to learn more about the subject. The author draws on his legal expertise, as well as his experience as Staff Director of the Governor's Commission to Review California Water Rights Law. The paper emphasizes the crucial role of water rights in California water management, and it points to the need for and present lack of a political consensus on water law reform. The author concludes by suggesting forces that could bring about interest-group realignments and other developments favorable to achieving the needed consensus on water law and management reform that so far has eluded Californians. Stanley Scott Assistant Director Institute of Governmental Studies March 1982

Water Allocation, Use, and Regulation in California

California Department of Water Resources (DWR) | October 30th, 2014

In California, water use and supplies are controlled and managed under an intricate system of common law principles, constitutional provisions, State and federal statutes

In California, water use and supplies are controlled and managed under an intricate system of common law principles, constitutional provisions, State and federal statutes, court decisions, and contracts or agreements. All of these components constitute the institutional framework for the protection of public interests and their balance with private claims in California’s water allocation and management.

Water and climate: Recognize anthropogenic drought

Nature Portfolio (Springer Nature) | August 27th, 2015

Water and Culture (Resource Management Strategy)

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

This resource management strategy report presents the emerging thinking of many California Water Plan Advisory Committee members and other stakeholders regarding the impo

This resource management strategy report presents the emerging thinking of many California Water Plan Advisory Committee members and other stakeholders regarding the importance of linking cultural considerations to water management. In many respects, this resource management strategy report represents more of an annotated outline than a fully developed strategy. Even so, the water plan stakeholders asked that this resource management strategy report be included, if only to improve awareness of the need for the strategy and to continue dialogue on what it should include. Water and culture are connected in myriad ways, with subtle and complex implications for water management in California. Some cultural relationships to water are so pervasive, they may be easy to overlook. Other cultural considerations are less apparent and may be difficult to recognize. Increasing the awareness of how cultural values, uses, and practices are affected by water management, as well as how they affect water management, will help inform policies and decisions. Even regulations reflect cultural values, particularly by how they are put into practice when water is viewed as a commodity, and all the more by the sum total of laws, regulations, and policies intended to control water. Water resources have shaped the history of California, contributing to the current social, cultural, and economic patterns across the state. The presence of freshwater sources has influenced the location of settlements and communities for hundreds, even thousands, of years. Water resources have also been pivotal to key economic activities, such as fishing, mining, agriculture, manufacturing, tourism, and recreation. These historic aspects of development continue to have ramifications for water managers today. Water and water-dependent resources also shape individual and collective experiences that contribute to individual and community well-being, sense of identity, and connection with the natural world. These experiences are inextricably linked to values, traditions, and lifestyles, which in turn inform perspectives and expectations regarding water resources and conditions. Cultural considerations by their nature are inherently linked to every resource management strategy. More importantly, the consideration of culture in water management decisions is, in many cases, legally mandated by State and federal laws. Utilizing cultural considerations in the framing, development, and promotion of management decisions is vital to ensuring legal compliance and sustainable practices.

Water and Energy in California

Public Policy Institute of California (PPIC) | December 6th, 2022

Water and Energy Sector Vulnerability to Climate Warming in the Sierra Nevada: Simulating the Regulated Rivers of California’s West Slope Sierra Nevada

California Energy Commission (CEC) | August 7th, 2012

Climate warming is expected to affect the beneficial uses of water in the Sierra Nevada, impacting nearly every resident of California. This paper describes the developme

Climate warming is expected to affect the beneficial uses of water in the Sierra Nevada, impacting nearly every resident of California. This paper describes the development and results from an integrated water resource management model encompassing water operations and hydropower generation for the west slope Sierra Nevada spanning the Feather River basin in the north to the Kern River basin in the south at the weekly time step. This model application includes management of reservoirs, run-of-river hydropower plants, water supply demand locations, conveyances, and instream flow requirement. Model validation indicates that most major hydropower turbine flows were simulated well, with wetter years modeled more effectively than drier years. The results of this work indicated that hydropower generation will be reduced by approximately 8 percent with 6°C (10.8°F) warming, consistent with other studies, with a conservative parameterization of no change in precipitation. Reservoir operations adapt to capture earlier and greater runoff volumes that result from earlier and greater runoff due to climate warming. Seasonal compensation in operations is insufficient to overcome warming mediated losses.

Water and Energy Sector Vulnerability to Climate Warming in the Sierra Nevada: Water Year Classification in Non?Stationary Climates

California Energy Commission (CEC) | July 31st, 2012

This paper explores the sensitivity of water indexing methods to climate change scenarios to better understand how water management decisions and allocations will be affe

This paper explores the sensitivity of water indexing methods to climate change scenarios to better understand how water management decisions and allocations will be affected by climate change. Many water management decisions, such as environmental flow requirements and water supply allocations, are based on numerical “water year type” designations. Water year type designations vary by region and index, but most are defined by some measure of runoff in the current water year compared to average historical runoff, with numerical thresholds categorizing year types. Climate change is anticipated to alter the timing and volume of runoff, and change the relative frequency of water year types as presently defined. California’s Sacramento Valley and San Joaquin Valley Indices are used as a case study to examine climatic changes. These indices provide a framework for allocating and transferring water among users. Streamflow estimates for 1951–2099 from the climate-forced Variable Infiltration Capacity hydrologic model are used to estimate potential changes in runoff and water year type frequency, using six global circulation models for the A2 and B1 emissions scenarios. Results vary by emissions scenario and global circulation model, but indicate that critically dry water years in the Sacramento Valley and San Joaquin Valley are expected to be about 8 percent and 32 percent more likely by the latter half of the twenty-first century, respectively, if water year type definitions remain unchanged. If current water year type thresholds are maintained, more years will be classified as dry and less water will be allocated for environmental outflows, perhaps failing to provide adequate hydrologic variability to support species, habitats, and ecosystems. If thresholds are redefined to reflect the historical distribution of year types, the burden of climate change falls to consumptive users and water exporters. This case study illustrates how water policy and allocation frameworks were designed assuming climatic stationarity, and that adapting water policy (or maintaining the status quo) affects which users bear the burden of climate change.

Water and Suspended-Sediment Flux Measurements at the Golden Gate, 2016-2017

San Francisco Estuary Institute (SFEI) | December 1st, 2017

Sediment is an important resource for San Francisco Bay (SFB), in the context of restoration projects, dredging operations, ecosystem health, and contaminant transport an

Sediment is an important resource for San Francisco Bay (SFB), in the context of restoration projects, dredging operations, ecosystem health, and contaminant transport and fate. Understanding the transport and fate of sediment in SFB is important to ecosystem researchers and managers. Previous studies have shown that sediment exchange at the estuary-ocean boundary of SFB (Golden Gate inlet) is the most poorly understood element of the SFB sediment budget, owing to logistical challenges that inhibit routine field observations, and the fact that net flux is a small fraction of the instantaneous peak values experienced on a daily basis. Improved understanding of sediment exchange at the estuary-ocean boundary of SFB is essential to updating SFB-wide sediment budgets, which account for sources, sinks, and storage of sediment (and sediment-associated contaminants). In this study, field observations of water and suspended-sediment fluxes at the Golden Gate were made over one ebb tide and one flood tide on three occasions: 1) 21-22 March 2016, following a large storm event that triggered the first flow into Yolo Bypass flood control structure since 2011 2) 23 June of 2016, during a period of low freshwater inflow; 3) 27-28 February 2017, following several large storms of the wettest winter in northern California in recorded history.

Water and the California economy

Public Policy Institute of California (PPIC) | May 17th, 2012

California’s economy can grow and prosper despite droughts and water shortages caused by a changing climate—but only if threats to the water system are addressed now.

California’s economy can grow and prosper despite droughts and water shortages caused by a changing climate—but only if threats to the water system are addressed now. So far, innovative water management has supported the needs of a growing population but serious concerns remain, including water supply reliability and declining groundwater basins.