ST. CLOUD — Minnesota officials said significant reductions in phosphorus levels are needed in St. Cloud-area lakes to meet quality standards and limit nuisance algae blooms.

A Minnesota Pollution Control Agency study found phosphorus reductions of 30-54 percent are needed in the 13-lake Sauk River chain, while reductions of 74-86 percent are needed in the smaller Eden Creek lakes. The chemical stimulates algae growth.

Most phosphorus in the lakes comes from so-called nonpoint sources such as runoff from farms and developed land. Conservationists will aim to slow the flow of phosphorus through voluntary measures since there isn’t a single big polluter contributing to the problem.

Stearns County soil and water conservation administrator Dennis Fuchs said more work could be done to help farmers adopt conservation practices.