Outside of the municipal service areas, individual parcels and communities rely on private wells and stream diversions for their water supply. Santa Cruz County, acting as a Local Primacy Agency for the State Water Resources Control Board, oversees small water systems serving between 5 and 199 water connections. The Drinking Water Program is designed to ensure that small public water supply systems deliver a reliable and adequate supply of groundwater or surface water to their customers. There are approximately 130 small water systems in the county serving roughly 2,500 households. Additionally, there are at least 8,000 private wells in Santa Cruz County that serve between 1 and 4 households. The map below shows the distribution of these private and small water systems in the county.