Goal 2: Improve Water Supply Reliability

Improve water supply reliability to meet human needs, reduce energy demand, and restore and maintain aquatic ecosystems and processes.


  • Increase water recycling
  • Increase water use efficiency
  • Reduce water demand
  • Increase water supply


Indicators with this Goal

  • Percent of drinking water suppliers which have instituted an affordable "lifeline" rate for low-income residential customers.
  • Number and estimated capacity of basins with years-long aquifer declines (known as overdraft) or projected future declines.
  • This metric describes the total water available from natural and managed flows and comes from the World Resources Institute (WRI). It is calculated as all water flowing into the catchment from upstream catchments plus any imports of water to the catchment minus upstream consumptive use, plus runoff in the catchment.
  • Baseline water stress measures total annual water withdrawals (municipal, industrial, and agricultural) expressed as a percent of the total annual available flow. Higher values indicate more competition among users. This indicator was used by the World Resources Institute in the Aqueduct 2.0 project.
  • Percentage of state and regional water supplied by the Delta.
  • Amount of Delta water used by sector (urban, agriculture, municipal, industrial) per season and per year
  • The maximum severity of drought during which core water demands can still be met, including social and environmental minimum requirements
  • The maximum earthquake intensity that can occur without causing more than some amount (e.g., $20 million) in damages due to water infrastructure disruptions, including levees
  • Energy required per unit of clean drinking water delivered.
  • Forest land conversion: Total acreage over time. When forests are converted to housing and other developments, many environmental qualities will be negatively impacted.
  • Groundwater stress measures the ratio of groundwater withdrawal relative to its recharge rate over a given aquifer. Values above one indicate where unsustainable groundwater consumption could affect groundwater availability and groundwater-dependent ecosystems. The indicator was used by the World Resources Institute (WRI) in the Aqueduct 2.0 project.
  • Magnitude and timing of managed system flows suitable for native riparian habitats and geomorphic processes. Healthy aquatic, riparian, and floodplain ecosystems require periodic high flow events, not just minimum flows.
  • Proportion of agricultural non-potable water needs--e.g. irrigation--met with non-potable water. The more non-potable water used for agriculture, the more potable water is available for drinking water and healthy aquatic ecosystems.
  • Use of recycled water as a percent of total water used. Re-using water reduces the demand on existing and new water sources and reduces costs and impacts.
  • Number of acres protected or enhanced in aquifer recharge areas. Natural recharge of underground water reservoirs may be the most cost-effective way to store and manage water.
  • Public awareness and perceptions of the role water plays in their lives and in the environment can affect how people vote to support candidates, taxes/assessments, and bond issues. It is both important to keep the public informed to support democracy and to track their knowledge and perceptions in order to develop policies and management actions.
  • Average water use /household, or /capita, 20% reduction by 2020 (per state law).
  • Return flow ratio measures the percent of available water previously used and discharged upstream as wastewater. This indicator was used by the World Resources Institute in the Aqueduct 2.0 project.
  • Annual withdrawal of ground and surface water as a percent of total annually renewable volume of freshwater.
  • Upstream protected land measures the percentage of total water supply that originates from protected ecosystems. Modified land use can affect the health of freshwater ecosystems and have severe downstream impacts on both water quality and quantity. The World Resources Institute used this indicator in the Aqueduct 2.0 project.
  • Upstream storage measures the water storage capacity available upstream of a location relative to the total water supply at that location. The World Resources Institute used this indicator in the Aqueduct 2.0 project.
  • Total agricultural, residential, and commercial water demand, i.e. demand for all uses other than environmental needs and basic human drinking water requirements.
  • The water footprint is the sum of the water used directly or indirectly to produce goods and services consumed by humanity. Agricultural production accounts for most of global water use, but drinking, manufacturing, cooking, recreation, washing, cleaning, landscaping, cooling, and processing all contribute to water use.
  • Volume of water re-used (same volume can count more than once) as a fraction of total water used, including onsite, or recycled.
  • Water Risk refers to the risk to water supplies from changes in climate and water withdrawals. The World Resources Institute used this indicator in the Aqueduct 2.0 project.
  • Water scarcity is a function of water availability and water use. This index is used by the global Environmental Protection Index and represents the over-use of water in a region.
  • Percent likelihood per year, over the next 20 years, of water shortage.
  • Years of average water use at current use levels represented by the current stored volume of water
  • Water stress index is typically defined as the relationship between total water use and water availability. The closer water use is to water supply, the more likely stress will occur in natural and human systems. This indicator has been used by the United Nations and others.
  • Distance traveled for units of drinking and irrigation water. The long-distance movement of water is one of the most energy-intensive activities in California and may cause social, economic, and environmental harm in the source areas.