Wisconsin Maintenance Program
State Statute 145 and Administrative Code SPS 383 have requirements for the maintenance and operation of all Privately Owned Wastewater Treatment Systems (POWTS) or septic systems in Wisconsin.
The tank part of the system requires regular maintenance. You must clean it our regularly to avoid sludge and scum build up, which can clog the outlet pipe or move out into the soil absorption field. This will clog the field and lead to a premature, costly failure of the system.
Most systems have a drainfield after the septic tank. The servicing frequency of an anaerobic treatment tank for a POWTS shall occur at least when the combined sludge and scum volume equals 1/3 of the tank volume. The common misconception that the tank must be pumped every three years is incorrect. Code only requires that systems be visually inspected at least once every three years. However, many owners pump at that time as preventative maintenance.
Many systems also have effluent filters in the tank on the outlet to the drainfield. Filters should be cleaned when your tank is serviced. Improperly maintained filters can damage the system or lead to back-ups.
Holding tank systems do not have a drainfield. They only hold wastewater until it can be pumped out by a liquid waste hauler. Holding tanks are serviced when the wastewater reaches a level of one foot below the tank's inlet invert. At this level, an alarm alerts the owner that servicing is needed.
County Duties
Counties as state agents are obliged to inventory and operate a program to track maintenance activity on septic systems within their jurisdiction. This program is more than just recording servicing events. Counties send maintenance reminder notices to landowners and follow up on delinquent properties.
Every county in Wisconsin has completed an inventory of all systems in their jurisdiction. The total is more than 750,000 systems state-wide! As of October 1, 2019, all POWTS must be part of a maintenance tracking program. Counties will send notices to owners when their system is due for maintenance.
Landowner Responsibilities
The owner of a POWTS is ultimately responsible for maintaining the system. Failure to do so is illegal, and that failure could lead to costly repairs or contamination of wells, groundwater and/or surface water.
Know when your system requires maintenance by keeping track of servicing events.
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POWTS Program Information
Any questions please contact DSPSSBPowtsTech@wisconsin.gov