NEW ULM - Despite a hot, dry summer of the kind that has caused problems in the past, Minnesota River water pollution levels continue to improve, according to recent Minnesota Pollution Control Agency (MPCA) tests.
Tests conducted over a three-week period last August found improvements in oxygen, phosphorus and chlorophyll during low flow, according to the MPCA. The results showed improved dissolved oxygen levels supporting fish and other aquatic life even during stressful conditions.
The MPCA linked positive results to the effectiveness of its 2004 plan to reduce phosphorus that affected wastewater treatment plants along the Minnesota River and its tributaries.
Staff photo by Fritz Busch
Extreme drought conditions expose large rocks on the west shore of the shrunken Minnesota River in Riverside Park in New Ulm Saturday. While water levels are low, the water appears quite clear. Recently released results of testing on the river show significant pollution level improvements, according to the Minnesota Pollution Control Agency (MPCA).
Glenn Skuta, MPCA water monitoring manager, said new strategies resulted in no dissolved oxygen water quality standard violations. Some of the strategies included avoiding stabilization pond discharges from June through September, upgrading inadequate sewage treatment in 12 cities and improved phosphorus removal in wastewater treatment.
Speaking at the Area Six Soil & Water Conservation District (SWCD) meeting last week at Turner Hall, MPCA Project Coordinator Larry Gunderson said recent studies show most river sediment comes from river banks and bluffs. Other sediment sources are runoff from ravines and upland ditches.
"Best-management practices like perennial vegetation and water storage can help reduce upland sediment," Gunderson said.
Minnesota Soil & Water Conservation District President Dr. Kathryn Kelly praised the efforts of Brown County SWCD board member Greg Roiger of rural Sleepy Eye and other board members in supporting buffer protection measures in an effort to control stream bank erosion and prevent flooding and resulting damage.
"The trouble is, people often build too close to river bluffs," Kelly said.
The MPCA recommends ways to reduce lake and stream nutrients that include:
For residents: using no-phosphorus fertilizer on lawns and gardens, keeping leaves and organic matter off streets by sweeping grass clippings and fertilizer spills and leaving a wide strip of deep-rooted plants along shore land and planting wildflowers, ornamental grasses, shrubs or trees that absorb and filter runoff.
For farmers: planting perennial crops on marginal cropland or converting to water retention areas and installing controlled drainage systems instead of traditional pattern tiling.
For cities: educating residents about keeping grass and organic matter out of storm sewers, enforcing littering and pet waste disposal laws, providing trash cans along popular pedestrian routes and educating contractors and excavators on best-management practices for mowing, fertilizer application and other maintenance work.
Fritz Busch can be e-mailed at firstname.lastname@example.org.