In Iowa, local boards of health have primary responsibility for regulation of sewer systems serving less than 15 people, while DNR has primary responsibility for larger (public) systems. In conducting their activities, counties must comply with the minimum state standards developed by DNR. If counties fail to adopt or enforce DNR standards for smaller systems, DNR has concurrent authority to force compliance by individuals and the counties with the minimum standards for on-site wastewater treatment and disposal.

The DNR standards specify siting and construction requirements relative to the primary and secondary treatment portions of the sewage disposal systems as well as minimum depth to groundwater, minimum separation distances to potable water sources, and maximum percolation rates for soils. The DNR standards are primarily a prescriptive code giving design criteria for each alternative type of secondary treatment system permitted. Counties have the authority to allow alternative or innovative performance based systems.

The DNR also licenses all commercial pumpers of septic tanks and livestock holding tanks. Although the DNR is responsible for licensing and regulation of commercial septic tank cleaners, the county boards of health are responsible for enforcement of the regulation.

Because of the responsibility the counties have in this area, the DNR in 1994 participated in the establishment of a training curriculum in on-site sewage disposal for county sanitarians. The curriculum is presented semi-annually for new sanitarians by a community college. The DNR has also been working actively to encourage those counties lacking an adequate enforcement program to upgrade their staff.

Be aware funding is available (*.pdf file) for loans to individuals to replace inadequate onsite sewer systems.

• Time of Transfer Inspection Program