Just the Facts: Land, Water, and Agriculture in the Colorado River Basin

Babbitt Center for Land and Water Policy (Babbitt Center) | March 1st, 2022

Juvenile Production Estimate (JPE) Calculation and Use/Application of Survival Data from Acoustically-tagged Chinook Salmon Releases Report

Delta Stewardship Council (Delta Council) | February 21st, 2014

Each year, NOAA’s National Marine Fisheries Service (NMFS) estimates the number of juvenile winter-run Chinook salmon expected to enter the Delta. NMFS’ June 4, 2009

Each year, NOAA’s National Marine Fisheries Service (NMFS) estimates the number of juvenile winter-run Chinook salmon expected to enter the Delta. NMFS’ June 4, 2009, biological and conference opinion on the long-term operation of the Central Valley Project and State Water Project provides an incidental take limit on natural juvenile winter-run based on the juvenile production estimate.

Kings River East GSA Groundwater Sustainability Plan (Revised)

Kings River East Groundwater Sustainability Agency (KREGSA) | July 5th, 2022

Klamath/San Joaquin/Sacramento Hydroclimatic Reconstructions from Tree Rings

California Department of Water Resources (DWR) | February 7th, 2014

This is a draft final report for Agreement Number 4600008850, “Klamath/San Joaquin/Sacramento Hydroclimatic Reconstructions”, signed October 13, 2010.  Work includes

This is a draft final report for Agreement Number 4600008850, “Klamath/San Joaquin/Sacramento Hydroclimatic Reconstructions”, signed October 13, 2010.  Work includes developing new and updated tree-ring chronologies, reconstructing specified streamflow and/or precipitation records in the Klamath, San Joaquin and Sacramento River Basins, and analyzing the time series properties of the reconstructions. These reconstructions allow assessment of hydrologic variability over centuries to millennia and give context for assessing recent drought events. Tasks on this project included field collections; laboratory work in sample preparation, dating and measurement; and statistical work in chronology development, reconstruction, and analysis of those reconstructions. The interpretation of the reconstructions includes five main components : 1) place instrumental-period flow statistics in a long-term context, 2) quantify droughts and wet periods, 3) identify cycles in wetness and dryness, 4) check consistency with other paleoclimatic data, and 5) assess reconstructed flow variations in the context of expected scenarios of climate. A total of 16 different hydroclimatic series – 11 flow records and 5 precipitation records, were reconstructed. This report summarizes the research project products and results. The Data and Methods section of this report describes the field collections and development of tree-ring chronologies, reconstruction modeling, and methods of analyzing reconstructions. The Results section focuses on the interpretation of selected key reconstructions for the Klamath, Sacramento, and San Joaquin basins. Annual time series of the 16 reconstructions are included as products in an appendix and in a digital spreadsheet.

Land Transitions and Dust in the San Joaquin Valley

Public Policy Institute of California (PPIC) | July 24th, 2022

The Sustainable Groundwater Management Act (SGMA) requires groundwater users to bring their basins into balance over the next two decades. In the San Joaquin Valley, this

The Sustainable Groundwater Management Act (SGMA) requires groundwater users to bring their basins into balance over the next two decades. In the San Joaquin Valley, this will mean taking more than 500,000 acres of agricultural land out of intensive irrigated production. Among other issues, this could potentially lead to air quality impacts if the lands become new sources of dust, especially windblown dust, which can have numerous negative short- and long-term health and environmental impacts. In addition, the changing climate may exacerbate risks as warmer temperatures can dry out soils and increase dust emissions. The overall air quality impact of transitioning agricultural land to new uses is nuanced, but proactive management can help to identify high-risk areas and at-risk communities, and direct effort and funding to the most cost-effective interventions.

LandFlex Program’s Guidelines

California Department of Water Resources (DWR) | December 8th, 2022

LandFlex is a program that will provide $25 million in block grants to local government agencies to grant to farmers who limit agricultural water use. Local government ag

LandFlex is a program that will provide $25 million in block grants to local government agencies to grant to farmers who limit agricultural water use. Local government agencies will work directly with farmers in critically overdrafted (COD) basins to identify lands that would reduce pumping impacts to nearby drinking water wells. Through financial incentives to farmers LandFlex will provide multiple community benefits such as drinking water well relief, groundwater overdraft prevention, and climate resilience. 

Large contribution from anthropogenic warming to an emerging North American megadrought

American Association for the Advancement of Science (AAAS) | April 17th, 2020

Severe and persistent 21st-century drought in southwestern North America (SWNA) motivates comparisons to medieval megadroughts and questions about the role of anthropogen

Severe and persistent 21st-century drought in southwestern North America (SWNA) motivates comparisons to medieval megadroughts and questions about the role of anthropogenic climate change. We use hydrological modeling and new 1200-year tree-ring reconstructions of summer soil moisture to demonstrate that the 2000–2018 SWNA drought was the second driest 19-year period since 800 CE, exceeded only by a late-1500s megadrought. The megadrought-like trajectory of 2000–2018 soil moisture was driven by natural variability superimposed on drying due to anthropogenic warming. Anthropogenic trends in temperature, relative humidity, and precipitation estimated from 31 climate models account for 47% (model interquartiles of 35 to 105%) of the 2000–2018 drought severity, pushing an otherwise moderate drought onto a trajectory comparable to the worst SWNA megadroughts since 800 CE.

Large global-scale vegetation sensitivity to daily rainfall variability

Nature Portfolio (Springer Nature) | December 11th, 2024

Click here for a plain language summary from NASA.

Click here for a plain language summary from NASA.

Learning from Crises to Build Urban Water Security

Rand Corporation (Rand) | January 15th, 2025

In this report, the authors examine the experiences of five cities — Cape Town, South Africa; Melbourne, Australia; São Paulo, Brazil; and Las Vegas, Nevada, and New O

In this report, the authors examine the experiences of five cities — Cape Town, South Africa; Melbourne, Australia; São Paulo, Brazil; and Las Vegas, Nevada, and New Orleans, Louisiana, in the United States — facing severe or catastrophic water supply risks to identify steps that could be taken ahead of time to mitigate those risks and build urban water security.

Lessons from California’s 2012–2016 Drought

American Society of Civil Engineers (ASCE) | October 1st, 2018

California’s 5-year drought has ended, even as its aftermath lingers. From 2012–2016 much or all of California was under severe drought conditions, with gre

California’s 5-year drought has ended, even as its aftermath lingers. From 2012–2016 much or all of California was under severe drought conditions, with greatly diminished precipitation, snowpack, and streamflow and higher temperatures. Water shortages to forests, aquatic ecosystems, hydroelectric power plants, rural drinking water supplies, agriculture, and cities caused billions of dollars in economic losses, killed millions of forest trees, brought several fish species closer to extinction, and caused inconvenience and some expense to millions of households and businesses. The drought also brought innovations and improvements in water management, some of which will better prepare California for future droughts. This paper summarizes the magnitude and impacts of the 2012–2016 California drought. The paper then reviews innovations arising from the drought in the larger historical context of water management in California. Lessons for California and for modern drought management are then discussed. Droughts in modern, well-managed water systems serving globalized economies need not be economically catastrophic, but will always have impacts and challenges, particularly for native ecosystems. In California and every other water system, droughts usefully expose weaknesses and inadequate preparation in water management. In this regard for California, managers of ecosystems and small rural water supplies had the most to learn.