Olmsted County accepts annual MS4 stormwater report; staff outlines education, mapping and inspection work

Olmsted County held a public hearing on its Municipal Separate Storm Sewer System (MS4) program and voted to accept the annual report describing stormwater activities, inspections and public-education work.

Skip Langer, manager of Olmsted Soil and Water Conservation District, presented the report. Langer explained MS4 covers the system of roads, ditches, pipes and best management practices that manage stormwater runoff and reduce pollutant loading into waters. He said the Minnesota Pollution Control Agency (MPCA) governs the permit; the current permit period runs 2020–2025 and the county will develop a new five-year plan later this year.

Langer summarized the county’s six minimum control measures, including public education and outreach, public participation, illicit discharge detection and elimination, construction-site runoff control, post-construction runoff control and internal pollution-prevention housekeeping. He said the county uses an “infiltration first” approach to stormwater treatment, followed by biofiltration and wet stormwater ponds.

Staff maintain and inspect structural best-management practices (BMPs) and stormwater ponds, Langer said, noting crews inspect 20% of BMPs annually and must inspect all of them over the five-year permit cycle. He described street-sweeping work that reclaimed 85 cubic yards of material (about 10 tandem loads) last year; the garbage is screened out and sand and other material is reused for road-building and slope work when appropriate.

Langer stressed outreach work, listing events (EarthFest, county fair, Arbor Day), a stormwater website, a hotline for complaints and technical assistance to landowners. He credited city stormwater staff as partners and said the county performs training for staff and contractors; he said about 85 staff attended recent training and many hold professional stormwater certifications through the University of Minnesota, MnDOT and the Minnesota Erosion Control Association.

During the public hearing, Nancy Wheeler Hanlon asked whether storm drains could be “adopted” and maintained by residents; Langer responded that adoption programs are typically administered by cities and suggested residents check city stormwater resources. A commissioner suggested staff use the hearing audience to provide salt-use education for residents; Langer offered practical guidance on pretreatment (brining), applying minimal salt at home, scraping and shoveling and limiting fertilizer use to reduce chloride and nutrient loading.

After a public-comment period, a commissioner moved to accept the MS4 report; the motion was seconded and the board voice-voted in favor. The transcript shows the motion carried.