At such time as a public sewer becomes available to a property served by an on-site wastewater treatment and disposal system, as provided in Section 95.05, a direct connection shall be made to the public sewer in compliance with these Sanitary Sewer chapters and the on-site wastewater treatment and disposal system shall be abandoned in accordance with federal, State, and County regulations and filled with suitable material.
(Code of Iowa, Sec. 364.12[3f])