Rare testing opportunity on Minnesota River shows positive results in reducing phosphorus
The Minnesota Pollution Control Agency (MPCA) is releasing results of testing on the Minnesota River that shows significant improvements in pollution levels in the river.
For three weeks in August, MPCA staff monitored a 20-mile stretch of the Minnesota River to see if this hot, dry summer caused low dissolved oxygen, which has been a problem under similar conditions in the past.
The results pleased MPCA scientists because they showed that dissolved oxygen levels are good and supportive of aquatic life even during stressful environmental conditions, such as low flow and high temperatures.
These results also point to the effectiveness of a 2004 MPCA plan and a phosphorus reduction permit that affected wastewater treatment plants along the Minnesota River and its tributaries.
According to Glenn Skuta, MPCA water monitoring manager, wastewater treatment plants along the affected stretch of river implemented several working phosphorus-reduction strategies.
Some of these strategies include:
Stabilization ponds avoiding discharge from June through September.
Upgraded wastewater treatment for 12 communities with inadequate sewage treatment.
Improved phosphorus removal in wastewater treatment that surpassed permitted goals for wastewater phosphorus loading to the basin ahead of schedule.
The permit also established a phosphorus trading program to allow new and existing permitted facilities flexibility in how they comply with wastewater effluent limits.