Department of Natural Resources issues final stormwater permits to Columbia, Boone County and university

JEFFERSON CITY, MO, AUG. 3, 2026 – The Missouri Department of Natural Resources will issue a final site-specific Municipal Separate Storm Sewer System (MS4) permit Aug. 1, 2026. The permit authorizes the city of Columbia, Boone County and University of Missouri (co-permittees) to discharge municipal stormwater to waters of the state.

The co-permittees are responsible for managing and operating their stormwater system, which is subject to the terms of this Phase II MS4 permit. The permit area is based on the permittees’ MS4 service areas, derived from the results of the U.S. Bureau’s 2020 Decennial Census. This regulated area consists of the stormwater system, which includes municipal streets, catch basins, curbs, gutters, ditches, artificial channels and storm drains.

On Dec.23, 2024, the co-permittees submitted a permit application to renew and update their existing National Pollutant Discharge Elimination System MS4 permit and Joint Stormwater Management Plan, both of which expired June 30, 2025. The permit was continued in effect, as allowed by Title 40 Code of Federal Regulations (40 CFR.) § 122.6, until the department issued or denied a new MS4 permit.

MS4 permittees are required to develop, implement and enforce a program to detect and eliminate illicit discharges, including non-stormwater discharges such illegal dumping to the MS4 system. Prior to receiving the co-permittees’ permit application, the department fielded approximately 30 citizen concerns regarding potential pollutants entering waters of the state from illegal dumping at large encampment sites in the Columbia MS4 service area.

Through stakeholder meetings and negotiations, the department and co-permittees agreed upon a modification to the city and county stormwater ordinances, and updates to the Joint Stormwater Management Plan to address the issue. On March 30, 2026, Boone County passed a modification to its county ordinance and on July 20, 2026, the city passed a modification to its city ordinance. The agreed upon language for their ordinances included “…human waste or litter from encampment activities or other gatherings in close proximity to any waterway…” to their current illegal dumping ordinances.

“Waste created by local encampments has had a direct and significant environmental impact on Columbia area waterways,” said Kurt Schaefer, director of the Department of Natural Resources. “We believed it was important for the co-permittees to add specific language to their ordinances that, if enforced, would effectively address those issues and allow the department to hold them accountable.”

This policy decision by the Department of Natural Resources will be carried out in all MS4 for all Missouri communities moving forward, according to Schaefer.

“The MS4 permit’s ability to address the issue of illegal dumping, particularly by reducing solid waste, domestic waste and hazardous waste generated from encampment sites close to waterways, will go a long way in protecting the public health and the environment for all Missouri communities,” he said.

MS4 permits are derived from the Federal Clean Water Act and covered under Code of State Regulations 10 CSR 20-6.200 Stormwater Regulations. They are an important regulatory tool for protecting water quality through reducing pollutants associated with discharges of urban stormwater runoff into waters of the state. These permits are effective for five years, which provides an opportunity to address or incorporate any emerging contaminants or technologies into the renewed permit for the regulated MS4 communities.

For more information about the final permit, contact the Missouri Department of Natural Resources, Water Protection Program, P.O. by telephone at 573-522-4502 or by email at MS4@dnr.mo.gov.

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