WILLMAR -- Efforts to reduce phosphorus reaching the Minnesota River are producing results, according to the Minnesota Pollution Control Agency.
Staff with the MPCA monitored the lower 20 miles of the river during August, when water temperatures were bathtub warm and flows were at a 24-year low.
They found oxygen levels were sufficient to support fish and other aquatic organisms.
It was a far cry from 1988, when similar temperature and flow conditions led to a widely reported fish kill in the lower reaches of the river.
The MPCA attributes much of the improvement to the gradual, but steady reduction of phosphorus in the river. In announcing the findings on Monday, the agency cited major improvements at 12 wastewater treatment plants in the basin as one of the important strategies.
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Lots of work of all types is taking place in the upper reaches of the Minnesota River to make possible the good news.
Farmers are adopting a wide variety of strategies to reduce erosion and reduce the potential for nutrients to reach waterways, noted Warren Formo, director of the Minnesota Water Resource Center.
"People don't really know about it,'' said Formo. It can be difficult to quantify the reduction in non-point sources of phosphorus. And, many of the improvements are being made farm by farm, and not in ways that would be readily apparent to the general public. Farmers are individually making choices to reduce the amounts of nutrients they apply, change tillage practices, or employ cover crops and other strategies to improve their bottom line while reducing nutrient losses to the waterway, he explained.
One of the major improvements -- yet often unnoticed -- is occurring on the lands where the farmer-owners of the Southern Minnesota Beet Sugar Cooperative are raising sugar beets. The cooperative has been encouraging its growers to plant an early season cover crop. The practice boosts overall yields while also reducing erosion and the amount of phosphorus reaching waterways.
This year, the cooperative's growers employed the cover crop practice on 86,232.1 acres, and in so doing helped keep 16,100 pounds of phosphorus from reaching waterways, according to audited figures provided by the cooperative.
It also assists its producers with a range of other projects, such as excluding cattle from waterways, as part of an overall campaign to reduce phosphorus.
Louise Knieper, manager of environmental affairs for Southern Minnesota Beet Sugar Cooperative, said the cooperative has seen steady, incremental growth in the adoption of practices by its member-growers that serve to improve yields and reduce sediment.
Patrick Moore, director of Clean Up the River Environment, credits the phosphorus reduction in the river to changes in how both point and non-point sources are managed.
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He pointed to taxpayer-supported initiatives that have been producing results in the basin, such as incentives for septic system upgrades. More than 30,000 septic systems have been upgraded as a result.
And without a doubt, the major investments made to wastewater treatment plants in the basin have been very important, he said.
Moore said CURE was organized in part due to concerns about the wastewater plant in Montevideo, where raw sewage was discharged into the river during high flow periods. Today, Montevideo is among the dozen communities that have made major investments to upgrade their wastewater plants and in particular, meet new, more stringent phosphorus standards.
Improvements made possible by Willmar's investment in a new wastewater treatment plant are some of the most significant. The new plant is expected to reduce phosphorus discharges from Hawk Creek where it meets the Minnesota River by 55 percent.
Moore said a growing awareness and appreciation of the river by the public is perhaps one of the most important of the changes. When CURE was organized in the early 1990s, the river was too often treated as an open sewer. Today, he said attitudes have changed as people realize the value of the resource and the worth of investing in protecting it.
