MINNEAPOLIS (AP) — The stretch of the Mississippi River that flows through the Twin Cities area is in better shape than it was 40 years ago, but a new report warns of some emerging threats.

The report from the National Park Service and an environmental group looks at the 72-mile stretch that makes up the Mississippi National River and Recreation Area.

Bald eagle populations have surged since the 1960s. Fish populations are doing well even though mercury and PCB contamination have made some of them unsafe to eat.

On the bad side, the report warns that the river is running faster than it used to because of increased runoff from farm fields and cities. That means more erosion and more chemicals and sediment in the river.