The American Concrete Pipe Association bestowed its 2010 Project Achievement Award on the team behind an arterial highway in Minnesota that used concrete pipe and boxes to address environmental challenges. Photo: American Concrete Pipe Association

The Scott County (Minn.) Highway Department and Minnesota DOT (MnDOT) attained a 2010 American Concrete Pipe Association (ACPA) Project Achievement Award for the way they used concrete pipes and boxes on a section of CSAH 21, an arterial highway in Scott County south of Minneapolis/St. Paul.

The project's design and construction team overcame obstacles including environmental considerations related to wetlands, wildlife, and stream crossings; planning and design concerns tied to pedestrian underpasses; and increased dead load cover of an existing concrete sanitary sewer.

“The project is a great example of sACPA President Matt Childs. “It sets an example that specifiers and DOTs across the nation can emulate.”

Underground construction included relocating a large-diameter reinforced concrete pipe for a sanitary sewer bypass and 12- to 60-inch concrete pipe for storm sewers and culverts.

Aboveground, precast boxes provide environmentally benign pedestrian and wildlife crossings that also control stormwater runoff.

For example, one stream crossing was facilitated by placing a low-flow box culvert alongside a second box culvert at a higher elevation, which will accommodate high-flow spring runoff and wildlife passage the rest of the year. A second dual-barrel culvert stream crossing includes a weir wall in one culvert to maintain a low-flow channel during low-flow periods.

A separate precast wildlife crossing was placed at a higher plateau near a wooded area, which also lets Sioux Community members access both sides of their land for hunting and syrup gathering in the fall.

Additional details are available at