Federal and state laws require that the District operate an industrial waste program. The Wisconsin Department of Natural Resources approved the District's program in 1983.

MMSD regulates industrial wastewater to:

• Help protect Lake Michigan.
• Prevent the discharge of pollutants that could damage sewers or treatment plants.
• Maintain high quality production of Milorganite fertilizer.
• Avoid violations of the District's discharge limits from our treatment plants.

The District currently issues permits to approximately 150 industrial facilities. Permits implement a combination of environmentally-based local limits and federal technology-based limits.

To make sure industrial users are following the rules, both MMSD and the regulated facilities collect samples. The District inspects each facility at least once per year to review the operations generating wastewater. If violations are found, enforcement action can range from warning letters to litigation seeking penalties up to $10,000 per day per violation.

This program has been very successful, reducing pollutants by 90% or more in many cases.
Source Reduction Effectiveness Analysis

The Industrial Waste Pretreatment Program also ensures that industrial facilities pay user charges in proportion to their load on the sewerage system.