To the north, lies the Bay Area IRWM region. Most of the Pajaro River watershed, including the Corralitos sub-watershed, is within the adjacent Pajaro River Watershed IRWM region.

The Region relies on surface and groundwater sources within its boundaries. The Region includes multiple water agencies. The City of Santa Cruz is the largest municipal water provider, there are several large water districts, numbers small drinking water systems, and thousands of individual well users.

The IRWM Region is situated on the northern end of Monterey Bay, 65 miles south of San Francisco. The Region’s boundaries were determined on the basis of common water management issues, regulatory, and jurisdictional boundaries with the intent to facilitate effective planning and project implementation. The IRWM boundary generally mirrors Santa Cruz County, and includes approximately 75% of the County’s ~198,000 residents and 85% of the geographic extent of County.