Industrial Pretreatment

Industrial Treatment

The term "pretreatment" refers to the requirement that non-domestic sources discharging wastewater to publicly owned treatment works (POTWs) control their discharges, and meet limits established by EPA, the State of Maine, or the local municipality on the amount of pollutants allowed to be discharged.

Control of Pollutans

The control of the pollutants may necessitate treatment prior to discharge to the POTW (therefore the term "pretreatment"). Discharge limits may often be met by the non-domestic source through pollution prevention techniques (product substitution, recycle and reuse of materials, more efficient production practices, improved environmental management systems, etc.), pretreatment of wastewater, or implementation of best management practices.

Discharge Restrictions

Certain discharges are restricted due to the potential to cause problems with the POTW system, including pass through and interference, or the sewer lines. The prohibitions are general and specific in nature. Visit the Prohibit Discharges page for information on prohibitions.


Implementation of an industrial pretreatment program assists the CA in complying with its discharge limits and sludge management program. As such, industry compliance and CA compliance are directly linked.