Certificate of On-Site Systems Approval (COSA)
Municipal code requires a home with a septic system or well to have a COSA prior to the transfer of ownership. The seller is responsible for obtaining this certificate, which certifies a registered engineer has tested the on-site systems, that they are adequate for the home they serve, and that they meet code requirements. The test results and other data collected are submitted to the On-Site Section for review and issuance of the COSA. The Department randomly selects systems for site inspection.
If code required separation distances cannot be met, a home may be eligible for a separation distance waiver for the well or septic system, which is determined on a case-by-case basis.
Subdivision Using Water and Wastewater systems
New Subdivisions within the Municipality of Anchorage that will be served by well and/or septic systems require a review. The subdivision review includes assessment of site conditions and the ability of the site to support these systems. Costs of subdivision reviews are included in the fees paid to the Planning Department.
The On-Site Water and Wastewater Section requires excavators, engineers, well drillers and well pump installers to be certified. The On-Site Section conducts certification seminars for engineers, excavators, well drillers and well pump installers for this purpose.
Definition for terms commonly used in relation to wells and septic systems.