Private Septic Systems

In Iowa, local boards of health have primary responsibility for regulation of sewer systems serving 4 homes or fewer or less than 15 people, while the Iowa DNR has primary responsibility for larger (public) systems. In conducting their activities, counties must comply with the minimum state standards developed by the Iowa DNR. If counties fail to adopt or enforce state standards for smaller systems, the Iowa DNR has concurrent authority to require compliance by individuals and the counties with the minimum standards for onsite wastewater treatment and disposal.

The Iowa DNR standards specify sitting and construction requirements relative to the primary and secondary treatment portions of the sewage disposal systems, minimum depth to groundwater, minimum separation distances to potable water sources, and maximum percolation rates for soils. The Iowa 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 Iowa DNR is responsible for licensing commercial septic tank pumpers/cleaners, and the county boards of health are responsible for enforcement of the septic regulations and inspections. In addition, the Iowa DNR certifies time of transfer septic system inspectors for inspections at the time of sale for buildings with private sewage systems.

Because of the responsibility the counties have in this area, the Iowa DNR provides an annual training for new county sanitarians. The Iowa DNR actively works with the counties to improve their enforcement programs and train their staff. The Iowa DNR has partnered with Des Moines Area Community College (DMACC) to develop a training center and curriculum covering onsite (private) wastewater systems. The training is provided statewide at various locations at least 10 times annually and covers all topics related to onsite wastewater systems. The Onsite Wastewater Training Center of Iowa, located at the DMACC Ankeny campus, includes numerous displays of onsite wastewater technology. The training is designed for county sanitarians, septic system installers, pumpers, and designers, but it is open to everyone.

Funding is available for loans to individuals to replace inadequate onsite sewer systems.  Please see the following links for more information in individual septic system loans: OSWAP Loan Program and USDA Rural Development.

Septic System Diagram
County Sanitarian List
Treatment Overview


Proposed Rulemaking, Onsite Wastewater:

The Iowa DNR is proposing to initiate rulemaking for 567 IAC Chapter 69 for the purpose of addressing proposed legislation in Senate File 511 (SF511) regarding maintenance requirements, including designation of whom is allowed to perform maintenance on peat moss bio filter systems, recirculating textile filter systems, or anaerobic treatment units.

Please see the following Summary of the proposed changes to Chapter 69. A stakeholder meeting to discuss the proposed changes was held on November 1, 2019. Comments from the meeting are currently being reviewed.

Please contact Cory Frank at cory.frank@dnr.iowa.gov or 515-725-8404 with any questions on the proposed changes.


Iowa Administrative Code Chapters regarding septic systems and onsite wastewater:

Chapter 68: Septic Tank Cleaners 
Chapter 69: Onsite Wastewater Treatment and Disposal 
Chapter 93: Onsite Wastewater Systems Assistance Program 


Helpful Links:

US EPA: Septic (Onsite) Systems
Onsite Wastewater Training Center 
Iowa Environmental Health Association 
Iowa Onsite Wastewater Association 
National Onsite Wastewater Recycling Association