The District provides wastewater collection services through a network of neighborhood pipelines that flow into pipelines and facilities owned by the South San Luis Obispo County Sanitation District (SSLOCSD), which is responsible for treatment and disposal. The SSLOCSD customers include the customers of OCSD as well as those of the cities of Arroyo Grande and Grover Beach. Since the OCSD does not control the operations of SSLOCSD, the financial statements and audit of the SSLOCSD are separate from the OCSD. OCSD operations are regulated by the Central Coast Regional Water Quality Control Board.