California Statewide Groundwater Elevation Monitoring (CASGEM) Status Report 2012

California Department of Water Resources (DWR) | April 23rd, 2012

Senate Bill X7 6 (SBX7 6) (Chapter 1, Statutes 2009) added provisions for Groundwater Monitoring to Division 6 of the Water Code (Water Code § 10920 et seq.), and author

Senate Bill X7 6 (SBX7 6) (Chapter 1, Statutes 2009) added provisions for Groundwater Monitoring to Division 6 of the Water Code (Water Code § 10920 et seq.), and authorizes the Department of Water Resources (DWR) to establish permanent, locally managed, groundwater-elevation monitoring and reporting in all of California's 515 alluvial groundwater basins. To implement SBX7 6, DWR developed the California Statewide Groundwater Elevation Monitoring (CASGEM) program. SBX7 6 requires DWR to report to the Governor and the Legislature by January 1, 2012, and thereafter in years ending in "5" or "0" regarding the findings of this program. The purpose of CASGEM is to establish a program of regular and systematic monitoring of groundwater elevations and to track seasonal and long-term trends in groundwater elevations statewide. The law directs DWR to rely and build upon the many established, local, long-term groundwater monitoring and management programs conducted by local entities throughout the state. DWR's role is to coordinate the CASGEM program, to work cooperatively with local entities, and to maintain the submitted groundwater elevation data in a manner that is readily and widely available to the public. Collection and evaluation of groundwater elevation data throughout the state is an important fundamental step toward improving management of California's groundwater resources. Within the first two years of program development, DWR has met the requirements specified in SBX7 6 to establish a statewide groundwater elevation monitoring and reporting program by January 1, 2012.

California Water Supply And Demand: Technical Report

Stockholm Environment Institute (SEI) | February 10th, 2011

The California Water Supply and Demand Model (CWSD) examines the ways in which California’s water supply and demand are likely to be affected by climate change; its pur

The California Water Supply and Demand Model (CWSD) examines the ways in which California’s water supply and demand are likely to be affected by climate change; its purpose is to serve as a base for quantifying these impacts in economic terms. California’s water future is modeled under conditions of no adaptation to climate change, and under several projected water use adaptation scenarios taken from the literature; climate change adaptation scenarios include water used for energy, the urban or residential sector, and agriculture. The main CWSD compares key categories of water inputs and outputs on a month-by-month basis to capture seasonality in water availability. A supplementary model allows for the main model’s beginning surface reservoir storage to result from water supply and demand interactions over a stylized previous 100 years. Three areas of water use are both especially critical and vulnerable to climatic change: the energy, agriculture, and urban sectors. In the energy module, water demand is a based on different scenarios of coal, nuclear and renewable power use, conservation technology, state population trends, and projected temperatures. In the agriculture module, crop and animal water use by county is a function of projected summer temperatures by county. In the urban module, residential, industrial/commercial, and public water use are based on projected levels of socio-economic growth.

California's Future

Public Policy Institute of California (PPIC) | January 18th, 2018

Water management in California has always been challenging. The state’s variable climate is marked by long droughts and severe floods, with stark regional differences i

Water management in California has always been challenging. The state’s variable climate is marked by long droughts and severe floods, with stark regional differences in water availability and demand. California has adapted by building a vast network of storage and conveyance facilities to deliver water from the wetter parts of the state to population and farming centers in the Bay Area, the San Joaquin Valley, and Southern California. The Sacramento–San Joaquin Delta is a fragile link in the state’s water supply network, and a plan to address supply reliability, known as California WaterFix, faces many hurdles. California’s extensive network of dams is aging. Agricultural demand is becoming less flexible, as farmers are increasing tree crops (especially nuts), which must be watered every year. Conflicts are growing between human water use and water needed to support fish and other wildlife. And the latest cycle of droughts and floods provides a glimpse of an uncertain future under climate change. California’s water management challenges are complex, but they can be addressed. Solutions will involve difficult and sometimes costly trade-offs, as well as contentious legal and political changes.

California’s Water Market, By the Numbers, Update 2012

Public Policy Institute of California (PPIC) | November 21st, 2012

This report provides a check-up on California’s progress with two innovative water management tools: water marketing and groundwater banking. These tools are part o

This report provides a check-up on California’s progress with two innovative water management tools: water marketing and groundwater banking. These tools are part of a modern approach that will enable California to manage its scarce water resources more flexibly and sustainably.

California’s Water: Storing Water

Public Policy Institute of California (PPIC) | October 1st, 2016

An extensive storage system plays a critical role in the state’s water management. This brief describes a number of ways to improve the management of reservoirs and

An extensive storage system plays a critical role in the state’s water management. This brief describes a number of ways to improve the management of reservoirs and groundwater basins to better prepare for droughts and manage floods. This publication is part of a briefing kit that summarizes a dozen of the state’s most pressing water management issues.

Can restoring water and sediment fluxes across a mega-dam cascade alleviate a sinking river delta?

American Association for the Advancement of Science (AAAS) | May 1st, 2024

Causes of Variability in Suspended‐Sand Concentration Evaluated Using Measurements in the Colorado River in Grand Canyon

American Geophysical Union (AGU) | July 29th, 2020

Rivers commonly exhibit substantial variability in suspended‐sand concentration, even at constant water discharge. Here we derive an approach for evaluating how m

Rivers commonly exhibit substantial variability in suspended‐sand concentration, even at constant water discharge. Here we derive an approach for evaluating how much of this variability arises from mean bed‐sand grain size. We apply this approach to the Colorado River in Grand Canyon, where discharge‐independent concentration of suspended sand varies by more than a factor of 23 (N = 1.4 × 106). Theory predicts that where concentration is controlled by bed‐sand grain size, concentration and grain size in suspension will be inversely correlated (i.e., coarsening of the bed causes suspended sand to become coarser in grain size and lower in concentration). Although the observed correlation is negative, riverbed grain size accounts for only 40% of the variability in concentration. The residuals vary by an order of magnitude; they arise from other processes, such as changes in topography or distribution of sand that cause shear stress to change at constant discharge, changes in the fine tail of bed‐sand grain sizes or changing bedforms. Both bed sand and the other factors influence concentration for durations from less than 1 day to several years. Predictions of concentration based on bed‐sand grain size (N = 4 × 104) are less accurate than predictions based on suspended‐sand grain size, probably because suspended sand is a natural integrator of sand‐transporting processes, giving more weight to those areas of the bed that exchange more sand with the flow. Although the causes of variability vary from one river to another, the approach illustrated here is applicable to any river in which concentration varies at constant water discharge.

Colorado River Basin August 2022 24-Month Study

U.S. Bureau of Reclamation (USBR) | August 16th, 2022

Colorado River Basin Reservoir Storage: where do we stand?

John Fleck | June 1st, 2025

Colorado River Drought Contingency Plan Authorization

United States Congress | April 16th, 2019

Authorized Drought Contingency Plans (DCPs) for the Upper and Lower Colorado River Basins, which required reduced Lower Basin deliveries beyond previous curtailment plans

Authorized Drought Contingency Plans (DCPs) for the Upper and Lower Colorado River Basins, which required reduced Lower Basin deliveries beyond previous curtailment plans at specified Lake Mead storage levels, committed Reclamation to additional water conservation efforts, and put in place plans to coordinate Upper Basin operations to enhance Lake Powell storage levels and prevent the loss of hydropower generation.