Central Valley Project Municipal and Industrial Water Shortage Policy Guidelines and Procedures

U.S. Bureau of Reclamation (USBR) | February 2nd, 2017

The Bureau of Reclamation (Reclamation) prepared the Central Valley Project (CVP) Municipal and Industrial (M&I) Water Shortage Policy (WSP) Environmental Impact Stat

The Bureau of Reclamation (Reclamation) prepared the Central Valley Project (CVP) Municipal and Industrial (M&I) Water Shortage Policy (WSP) Environmental Impact Statement (EIS) to evaluate the potential impacts of CVP M&I WSP alternatives. A Record of Decision was signed on November 13, 2015, to implement Alternative 4 (Appendix A), Updated M&I WSP (preferred alternative). The purposes of the M&I WSP are to: Define water shortage terms and conditions for applicable CVP Contractors. Determine the quantity of water made available to CVP Contractors from the CVP that; together with the M&I Contractors’ drought water conservation measures and other Non-CVP water supplies, would assist the M&I Contractors in their efforts to protect public health and safety (PHS) during severe or continuing droughts. Provide information to Contractors for their use in water supply planning and development of drought contingency plans.

Changes in Evapotranspiration of Agricultural Crops in Kern County during the 2014-2015 Drought Years

University of California, Davis (UC Davis) | September 5th, 2017

The 2012-2015 drought in California has major impacts for agricultural water users in Kern County. Farmers shifted crop planting patterns and irrigation scheduling to min

The 2012-2015 drought in California has major impacts for agricultural water users in Kern County. Farmers shifted crop planting patterns and irrigation scheduling to minimize profit loss with water shortage. This report models the changes in crop evapotranspiration from 2011 to 2014 and 2015 using the remote-sensing-based METRIC model developed by the University of Idaho. Results show that rather than universal losses of acreage and productivity, farmers reduced acreage on annual crops while increasing acreage on low-water-use new orchards. Productivity increased on the annual crops that remained in production, perhaps due to fallowing less productive land. High-value crops such as citrus and grapes saw increases in both acreage and productivity. Remote-sensing-based evapotranspiration mapping provides an important tool to policymakers by providing field-based estimates of a wide range of farmer responses to drought including planting, fallowing, under-irrigation, and, if combined with productivity models, changes in revenue. 

Changes in water consumption linked to heavy news media coverage of extreme climatic events

American Association for the Advancement of Science (AAAS) | October 25th, 2017

Public awareness of water- and drought-related issues is an important yet relatively unexplored component of water use behavior. To examine this relationship, w

Public awareness of water- and drought-related issues is an important yet relatively unexplored component of water use behavior. To examine this relationship, we first quantified news media coverage of drought in California from 2005 to 2015, a period with two distinct droughts; the later drought received unprecedentedly high media coverage, whereas the earlier drought did not, as the United States was experiencing an economic downturn coinciding with a historic presidential election. Comparing this coverage to Google search frequency confirmed that public attention followed news media trends. We then modeled single-family residential water consumption in 20 service areas in the San Francisco Bay Area during the same period using geospatially explicit data and including news media coverage as a covariate. Model outputs revealed the factors affecting water use for populations of varying demographics. Importantly, the models estimated that an increase of 100 drought-related articles in a bimonthly period was associated with an 11 to 18% reduction in water use. Then, we evaluated high-resolution water consumption data from smart meters, known as advanced metering infrastructure, in one of the previously modeled service areas to evaluate breakpoints in water use trends. Results demonstrated that whereas nonresidential commercial irrigation customers responded to changes in climate, single-family residential customers decreased water use at the fastest rate following heavy drought-related news media coverage. These results highlight the need for water resource planners and decision makers to further consider the importance of effective, internally and externally driven, public awareness and education in water demand behavior and management.

City of Fresno et al v. U.S. Bureau of Reclamation et al

United States Court of of Federal Claims | December 17th, 2024

In this case, we are called upon to review how the federal government resolved a particular dispute over water distribution during the drought-ridden year of 2014

In this case, we are called upon to review how the federal government resolved a particular dispute over water distribution during the drought-ridden year of 2014. As we explain in more detail below, individual growers, irrigation districts (which provide water to farms), water districts (which provide water to municipalities), and the City of Fresno, all located within the area served by the Central Valley Project (“CVP” or “Project”), sued the United States (“government”) over its failure to deliver water they contend they were entitled to under a series of contracts. The government defended its water allocation decisions by pointing to obligations it had under other contracts, to deliver water to another set of entities. Through adjudication of a series of motions, the Court of Federal Claims dismissed several of the plaintiffs’ claims and granted summary judgment to the government on all remaining claims.

Climate change and California drought in the 21st century

National Academy of Sciences (NAS) | March 31st, 2015

Climate science has advanced over decades from an initial focus on the development and use of numerical models of Earth’s climate and compilation of rich netw

Climate science has advanced over decades from an initial focus on the development and use of numerical models of Earth’s climate and compilation of rich networks of obser- vational data, to now being in a position to“detect” and “attribute” specific impacts and events to anthropogenic climate change. Recent analyses have thus established the“fingerprint” of anthropogenic climate change in an increasingly diverse array of meteorological and hydrological phenomena around the world, from heat waves to coastal damages during extreme tides and storms, flooding from more intense precipitation events, and severe drought. In a new study published in PNAS, Diffenbaugh et al. now add weight to the accumulating evidence that anthropogenic climatic changes are already influencing the frequency, magnitude, and duration of drought in California. The authors show that the increasing co-occurrence of dry years with warm years raises the risk of drought despite limited evidence of a trend in precipitation itself, highlighting the critical role of elevated temperatures in altering water availability and increasing overall drought intensity and impact.

Climate Change and Future Water Availability in the United States, Chapter E of U.S. Geological Survey Integrated Water Availability Assessment—2010–20

U.S. Geological Survey (USGS) | January 15th, 2025

The following are the key points of this chapter:  The steady rise in global temperature as a result of human activity is causing changes in Earth’s water cycle.

The following are the key points of this chapter:  The steady rise in global temperature as a result of human activity is causing changes in Earth’s water cycle. The amount of water stored within and moving between vapor, liquid and frozen components of the water cycle is shifting, with significant consequences for water availability. Climatic drivers underlie regional or local changes in water supply and their socioeconomic impacts. Threats to the quantity and quality of water available for humans and ecosystems in North America include increases in drought, aridification, and fire weather; heavy precipitation and flooding; cryosphere decline; rising surface-water temperatures; and saltwater intrusion in coastal areas. An understanding of how changes in the major climatic drivers impact the water cycle and the accurate simulation of impacts in hydrological models are crucial to predicting future water availability and developing adaptation strategies to ensure human and ecosystem water supplies. Companion chapters: U.S. Geological Survey Integrated Water Availability Assessment—2010–20, Chapter A Water Supply in the Conterminous United States, Alaska, Hawaii, and Puerto Rico, Water Years 2010–20, Chapter B 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  Integrated Water Availability in the Conterminous United States, 2010–20, Chapter F 

Climate change and the aridification of North America

National Academy of Sciences (NAS) | May 19th, 2020

Discussions of droughts and their impacts often center on the lack of precipitation, just as assessments of hydrologic impacts under a changing climate most ofte

Discussions of droughts and their impacts often center on the lack of precipitation, just as assessments of hydrologic impacts under a changing climate most often focus on how average precipitation in a given locale is likely to change in the future. Within climate science, however, focus has begun to include the growing role warming temperatures are playing as a potent driver of greater aridity: hotter climate extremes; drier soil conditions; more severe drought; and the impacts of hydrologic stress on rivers, forests, agriculture, and other systems. This shift in the hydrologic paradigm is most clear in the American Southwest, where declining flows in the region’s two most important rivers, the Colorado and Rio Grande, have been attributed in part to increasing temperatures caused by human activities, most notably the burning of fossil fuels. Warmer summers are also likely to reduce flows in the Columbia River, as well as in rivers along the Sierra Nevada in California. Now, an important study [Increased drought severity tracks warming in the United States’ largest river basin, J.T. Martin et al] documents how warming is also causing flow declines in the northern Rocky Mountains and in the largest river basin in the United States, the Missouri. This work further highlights the mechanisms behind the temperature-driven river flow declines and places more focus on how anthropogenic climate warming is progressively increasing the risk of hot drought and more arid conditions across an expanding swath of the United States.

Climate Change and Water Supply Security: Reconfiguring Groundwater Management to Reduce Drought Vulnerability

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

Periodic droughts, projected to become more frequent and severe with climate change, present a significant planning challenge for California’s water agencies. This r

Periodic droughts, projected to become more frequent and severe with climate change, present a significant planning challenge for California’s water agencies. This research examined approaches to reducing drought vulnerability, focusing on five water agencies on California’s north and central coast that rely on local and regional sources of water. Curtailing water use is the principal response to drought. In contrast, this project highlights an important but underutilized proactive adaptation to improve water supply security during drought: the development of locally based groundwater drought reserves. While this approach represents an obvious solution in principle, it is uncommon to find it in practice, and this research provides insight into (1) motivating factors, (2) legal barriers and opportunities, (3) tools, and (4) policy options to support increased drought resilience and the development of drought reserves.

Climate change scenarios forecast increased drought exposure for terrestrial vertebrates in the contiguous United States

Nature Portfolio (Springer Nature) | November 15th, 2024

Climate-driven disturbances amplify forest drought sensitivity

Nature Portfolio (Springer Nature) | June 7th, 2024