MINNEAPOLIS — An appeals court has upheld new water quality standards which are aimed at controlling algae in Minnesota’s rivers and streams.

The Minnesota Pollution Control Agency imposed the stricter rules recently as part of the Clean Water Act. But, some cities said it will costs millions to comply with the tighter standards.

A coalition of cities, along with soybean growers, asked the Minnesota Court of Appeals to stop intervene, saying the agency’s rulemaking process was flawed. According to a press release, the court rejected the challenge, which means wastewater treatment plants that discharge phosphorus into streams and rivers will have to comply with tougher standards.

Moorhead is among the cities that went to court. City leaders said it will cost $10 million to meet the new standards.