Water Quality & Supply

The San Diego region’s economic wellbeing and quality of life depends on ensuring a reliable supply of water to meet our existing and future water needs. SANDAG coordinates stormwater management, watershed planning, and water supply demand forecasting activities to ensure the availability of water for future growth.

Stormwater Management

SANDAG assists our local jurisdictions and regional projects in meeting their stormwater permit requirements, identifying areas where regional approaches would benefit regional water quality and watershed planning, as well as monitoring and responding to regional water supply issues. Additionally, SANDAG ensures that projects in the construction phase comply with applicable water quality licensing agreements, such as Construction General Permits, and develops project-specific Stormwater Pollution Prevention Plans. We also provide technical assistance, such as stormwater awareness surveys, to provide baseline information for developing public outreach programs and analyzing regional databases and GIS layers.

Watershed Planning

We encourage watershed planning throughout the region by participating in several local watershed councils and providing technical and staff assistance where appropriate. SANDAG maintains a GIS database that can delineate information regarding soil types, land uses, topography, demographics, and other data by watershed.

Water Supply Demand Forecasting

SANDAG and the San Diego County Water Authority work together to link future water supply needs with the forecasted growth within the region. The County Water Authority uses SANDAG’s most recent regional growth forecasts for water supply planning, and in turn, provides current information on the future supplies that will meet the growth forecast for the region.

Since the 1940s, the San Diego region has relied upon water imported from outside the county due to limited local surface and groundwater supplies. Currently, 70% to 95% of the region’s water supply is imported from the Colorado River and northern California.