Wastewater Systems Plan Review

Sewerage systems in Wisconsin are subject to the administrative rules of the Department of Natural Resources (DNR). A "sewerage system" is the collection of all structures, conduits and pipes, by which sewage is collected, treated, and disposed of, with the exception of building plumbing and the service pipes from the buildings to municipally owned sewers. Private Onsite Wastewater Treatment Systems (POWTS) are excluded from the definition of sewerage system and handled separately.

Plans for new construction or modification of a sewerage system must be submitted to the DNR for review and approval, prior to construction.

The Role of Department of Commerce

The Department of Commerce (Commerce) has administrative rules for building plumbing and non-municipal sewer lines, and for Private Onsite Wastewater Treatment Systems. A POWTS is a system that receives domestic quality wastewater and either retains it in a holding tank, or treats it and discharges into the soil, beneath the ground surface. Any system with a final discharge exposing treated wastewater upon the ground surface, or discharging directly into surface waters of the state, is subject to DNR regulation.

Joint DNR/Commerce Review Process

A POWTS that is classified as “large” and that receives domestic wastewater is subject to a joint agency review process involving both the DNR and Commerce. For additional information, please visit Large POWTS for Domestic Wastewater.

An onsite wastewater treatment system of any size that receives non-domestic (or a mixture of domestic and non-domestic) wastewater is subject to DNR regulation, but in certain circumstances Commerce will still issue an approval. For additional information, please visit Holding Tanks for Non-Domestic Wastewater or POWTS for Non-Domestic Wastewater.

Contact Information

Bureau of Watershed Management WT/2
101 South Webster St
PO Box 7921
Madison, WI 53707
ph: 608-267-7694
fax 608-267-2800
Watershed@dnr.state.wi.us

Last Revised: Thursday May 14 2009