Risk indicators for water quality, water shortage, and affordability combined into one risk score per square mile section, attributed to overlying state small water systems and domestic well records. Intended for use in the 2024 Combined Risk Assessment (part of the 2024 Needs Assessment). Please note that state small water systems and domestic wells are not subject to all requirements of the California Safe Drinking Water Act. The risk presented here should not be used to predict contamination or well failure at any given location.

This resource contains multiple layers - the PLSS section layer shows the risk scores for all areas of California. The Domestic Well layer shows the risk scores for PLSS sections with one or more domestic well record(s). The state small water system layer shows point locations of state small water systems joined with the risk scores of the underlying PLSS section.

Water quality data is from the 2024 Aquifer Risk Map.Water shortage data is from the Department of Water Resources Water Shortage Vulnerability Assessment Scoring.Socioeconomic/affordability data is from the Office of Environmental Health Hazard Assessment.

Domestic well record counts are from the Department of Water Resources OSWCR database, and state small water system counts/locations are from the Division of Drinking Water.

For more information please refer to the Needs Assessment Homepage.