Water Rights and Climate Change

Facing the threat of greater scarcity of water supplies, increased water demand, and limited water supply reliability, California has increased focus on actions to build resilience and meet California’s water needs through the 21st century.  The Water Boards have taken a variety of actions to respond to climate change.

As the patterns of runoff are projected to change and past conditions are no longer a reliable guide to future conditions, it is a good practice to consider impacts of climate change in water availability analyses.

Data and Tools

California has invested in considerable amount of research to understand how a changing climate will affect the State, and develop data, tools, and guidance relevant for water resources planning and management in California. Below are select links to climate change science and tools:

  • SGMA Climate Change Resources. California Department of Water Resources provides climate change data, tools, and guidance to support implementation of Sustainable Groundwater Management Act (SGMA).  The data include historical detrended precipitation, and reference evapotranspiration along with change factors for projected climate conditions centered around 2030 and 2070.  The hydrological data provide projected unimpaired stream inflows for major streams in the Central Valley, and streamflow change factors for areas outside of the Central Valley and smaller ungaged watersheds within the Central Valley.
  • Cal-Adapt. Web portal designed to provide access to the wealth of data and information that has been, and continues to be, produced by State of California's scientific and research community.  The data include daily temperature and precipitation for the historical period (1950-2005), and for future scenarios (2006-2100), along with relative humidity, wind speed, and surface solar radiation for a subset of models.  Historical and future daily hydrological data estimated using Variable Infiltration Capacity model include snow cover, soil moisture, runoff, water loss from plants, surface moisture and heat fluxes.
  • California’s Fourth Climate Change Assessment. Designed to assess the impacts and risks from climate change, the Fourth Assessment provides scientific foundation for understanding climate-related vulnerability at the local scale and informing resilience actions.

Related Resources

Applicants may want to review if a water management planning conducted for their area addressed climate change impacts, or if other permitting projects in their stream system have developed information that may be adapted to their project.  Examples of regional planning efforts that consider climate change include:

Have Questions?

For climate change inquiries, please contact Jelena Hartman at (916) 327-8621 or jelena.hartman@waterboards.ca.gov.

Application resources describe the Water Rights Permitting Process. For inquiries regarding filing an application to appropriate water, please contact Permitting Staff responsible for your county or area of interest.