South Lahontan

2023 Water Resilience Portfolio Progress Report

California Natural Resources Agency (CNRA) | October 31st, 2023

2024 Annual Water Supply and Demand Assessment Summary Report

California Department of Water Resources (DWR) | October 1st, 2024

This report summarizes the Department of Water Resources’ (DWR’s) review of Urban Water Suppliers’ Annual Water Shortage Assessment Reports (Annual Shortage Reports

This report summarizes the Department of Water Resources’ (DWR’s) review of Urban Water Suppliers’ Annual Water Shortage Assessment Reports (Annual Shortage Reports) for the State Water Resources Control Board (State Water Board). As directed by the California Water Code (CWC) §10644(c)(1)(B), this summary report includes water shortage information at the supplier level, as well as regional and statewide analyses of water supply conditions.

2025 Agricultural Water Management Plan Guidebook

California Department of Water Resources (DWR) | September 30th, 2025

Agricultural water suppliers in California have a long history of preparing agricultural water management plans (AWMPs) and implementing efficient water management practi

Agricultural water suppliers in California have a long history of preparing agricultural water management plans (AWMPs) and implementing efficient water management practices (EWMPs).  However, water management planning is not static; changing conditions and understanding of the system necessitate revisiting, adapting, and improving planning and implementation efforts. The five-year cycle AWMP is an opportunity for individual agricultural water suppliers to closely examine their practices and systems to find areas where operations can be improved and where water can be used more efficiently. An AWMP can also provide information and a record to the public on the agricultural water supplier’s stewardship of our limited water resources.

2025 Agricultural Water Management Plan Guidebook (Draft)

California Department of Water Resources (DWR) | July 23rd, 2025

The 2025 Agricultural Water Management Plan Guidebook (Guidebook) was prepared by DWR to assist agricultural water suppliers in understanding and complying with the requi

The 2025 Agricultural Water Management Plan Guidebook (Guidebook) was prepared by DWR to assist agricultural water suppliers in understanding and complying with the requirements of the Agricultural Water Management Planning Act (Division 6, Part 2.8 of the California Water Code), the Agricultural Water Measurement Regulation (Title 23, Division 2, Chapter 5.1, Article 2 of the California Code of Regulations), and AB 1668 Water Management Planning (Friedman, Statute of 2018). This Guidebook is intended to clearly identify information and elements required by the California Water Code (Water Code), provide guidance on how Agricultural Water Suppliers can address these requirements, and identify potential additional information Agricultural Water Suppliers can include in order to develop plans that are useful for their own operations and management and to improve long-term system reliability. This Guidebook also describes how Water Conservation Plans (WCPs) submitted to the United States Bureau of Reclamation (USBR), and Urban Water Management Plans (UWMPs) submitted to DWR, can be supplemented to satisfy the Water Code and Agricultural Water Measurement Regulation requirements.

21st century California drought risk linked to model fidelity of the El Niño teleconnection

Nature Portfolio (Springer Nature) | September 3rd, 2018

Greenhouse gas-induced climate change is expected to lead to negative hydrological impacts for southwestern North America, including California (CA). This includes a decr

Greenhouse gas-induced climate change is expected to lead to negative hydrological impacts for southwestern North America, including California (CA). This includes a decrease in the amount and frequency of precipitation, reductions in Sierra snow pack, and an increase in evapotranspiration, all of which imply a decline in surface water availability, and an increase in drought and stress on water resources. However, a recent study showed the importance of tropical Pacific sea surface temperature (SST) warming and an El Niño Southern Oscillation (ENSO)-like teleconnection in driving an increase in CA precipitation through the 21st century, particularly during winter (DJF). Here, we extend this prior work and show wetter (drier) CA conditions, based on several drought metrics, are associated with an El Niño (La Niña)-like SST pattern. Models that better simulate the observed ENSO-CA precipitation teleconnection also better simulate the ENSO-CA drought relationships, and yield negligible change in the risk of 21st century CA drought, primarily due to wetting during winter. Seasonally, however, CA drought risk is projected to increase during the non-winter months, particularly in the models that poorly simulate the observed teleconnection. Thus, future projections of CA drought are dependent on model fidelity of the El Niño teleconnection. As opposed to focusing on adapting to less water, models that better simulate the teleconnection imply adaptation measures focused on smoothing seasonal differences for affected agricultural, terrestrial, and aquatic systems, as well as effectively capturing enhanced winter runoff.

A brief geologic and hydrologic reconnaissance of the Furnace Creek Wash area, Death Valley National Monument, California

U.S. Geological Survey (USGS) | July 1st, 1964

A comparison of the taxonomic and trait structure of macroinvertebrate communities between the riffles and pools of montane headwater streams

Hydrobiologia (Springer) | May 30th, 2018

Macroinvertebrate community taxonomic and trait structure showed consistent differences between riffles and pools across 12 headwater streams in the Sierra Nevada (Cali

Macroinvertebrate community taxonomic and trait structure showed consistent differences between riffles and pools across 12 headwater streams in the Sierra Nevada (California) even as flows varied from wet to dry years and between seasons. Densities of Ephemeroptera, Plecoptera, Trichoptera, Elmidae, Orthocladiinae and Diamesinae midges, and mites were greater in riffles, whereas Tanypodinae, Chironominae, Sialis, and Pisidium were more abundant in pools. Pools had higher densities but estimated biomass was greater in riffles. Collector-gatherer and micropredator abundances were greater in pools whereas grazers, collector-filterers, and macropredators were more abundant in riffles. Stonefly shredders were most abundant in riffles but some caddis shredders were more abundant in pools. Trait state patterns were related to food resource and physical habitat differences between riffles and pools. Of the distinct pool–riffle differences we found among taxa, only about half conformed to expectations from the literature. Pool and riffle assemblages were most dissimilar at intermediate discharge and converged at low and high flows when one or the other habitat dominated. Bioassessment sampling will need to account for these flow-related differences. Benthic invertebrate communities in these mountain streams clearly differ between pools and riffles, but the relative extent of habitats and biological similarity shift with flow regime.

A geohydrologic reconnaissance of the Saratoga Spring area, Death Valley National Monument, California

U.S. Geological Survey (USGS) | March 1st, 1966

A global poleward shift of atmospheric rivers

American Association for the Advancement of Science (AAAS) | October 11th, 2024

A Guide for Using the Transient Ground-Water Flow Model of the Death Valley Regional Ground-Water Flow System, Nevada and California

U.S. Geological Survey (USGS) | November 4th, 2006

This report is a guide for executing numerical simulations with the transient ground-water flow model of the Death Valley regional ground-water flow system, Nevada and Ca

This report is a guide for executing numerical simulations with the transient ground-water flow model of the Death Valley regional ground-water flow system, Nevada and California using the U.S. Geological Survey modular finite-difference ground-water flow model, MODFLOW-2000. Model inputs, including observations of hydraulic head, discharge, and boundary flows, are summarized. Modification of the DVRFS transient ground-water model is discussed for two common uses of the Death Valley regional ground-water flow system model: predictive pumping scenarios that extend beyond the end of the model simulation period (1998), and model simulations with only steady-state conditions.