MPCA: Little Improvement In Minnesota River Basin

ST. PAUL, Minn. (AP) -- A new study says there's been a lack of significant improvement over the past two decades in the health of aquatic life in the Minnesota River basin.

It finds slight improvements in fish communities, including the return of smallmouth bass, walleyes and some pollution-sensitive species. The study says that's encouraging. But it also finds slight decreases in invertebrates such as aquatic insects, snails and mussels.

The Minnesota Pollution Control Agency released the study Monday. It covers the Minnesota River and its many tributaries, which drain nearly 17,000 square miles. It compares survey results from the early 1990s with data from 2009-10.

The report says there's little evidence that cleanup measures have helped much. It concludes more and better-targeted conservation efforts and water management practices are needed.

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