Water and drought play important roles in California's ecosystems. All biological organisms require water in order to function, and many of the region's animals and plants are well-adapted to the daily, seasonal, and annual cycles of this essential resource. Water serves critical roles in agriculture, industry, recreation, transportation, and maintenance of our environment, as well as our very quality of life.

Drought is a period of unusually persistent dry weather that lasts long enough to cause serious problems such as crop damage and/or water supply shortages. The severity of the drought depends upon the degree of moisture deficiency, the duration, and the size of the affected area (source: National Weather Service). A drought can be defined by the amount of precipitation in an area, by the amount of moisture in the soil, by surface and subsurface water supplies, or by water shortages affecting people.

Follow the links below and throughout the page to explore water and drought resources for the state of California.

State Resources:

• California's Department of Water Resources home page is a state resource with information about water resources in California that also contains a comprehensive drought page.
• The Association of California Water Agencies water crisis page provides information about the water shortage in the state.
• California Farm Water Coalition site houses information for farmers and highlights the importance of water for state agriculture.
• The California Urban Water Conservation Council, a partnership between different organizations that have an interest in conserving water, promotes efficient usage.

Regional and National Resources:

• The Automated Geospatial Watershed Assessment Tool (AGWA) is a GIS-based hydrologic modeling tool available for download.
• The Drought Impacts on Regional Ecosystems Network (DIREnet) is an association of researchers and land managers interested in documenting impacts on major ecosystems of the western United States resulting from drought-related processes.
• The Lower Colorado River Aquatic Gap Analysis Project examines the current level of aquatic biodiversity within a system to identify gaps in distribution and protection of species to better inform managers, planners, scientists, and policy makers.
• The National Integrated Drought Information System (NIDIS), implemented by the National Oceanic and Atmospheric Administration (NOAA), provides an integrated drought monitoring and forecasting system at federal, state, and local levels, including an "early warning system."
• The Vegetation Drought Response Index (VegDRI) is a valuable addition to the field of drought monitoring, with applications for the agricultural community.