Minnesota Waterfowl Association

One of the first steps in the wetland restoration process always involves idenitfying what wetlands have been altered. Sometimes this is as easy as looking at an air photo and indentifying the drainage ditches as in the picture to the right. On this 40 acre site, the wetlands were drained, but they were still too wet to effectively farm.

Once these drained wetlands are restored through RIM WRP, they will look similar to the surrounding land which is a Waterfowl Production Area. 

Sometimes the alteration of the wetlands goes beyond open drainage ditches. Here, we are taking soil borings in a drained wetland to determine how much sediment has ended up in the bottom of this wetland. The restoration of this wetland will involve the removal of the washed in sediment.

At right, you can see sediment removal in action. If the sites are dry enough, a large belly scraper and tractor can tackle the job very efficiently. The sediment is removed from the wetland and then placed back on the uplands.

Backhoes are also used to remove sediment when the conditions are wetter. In this photo, you can see a finished wetland restoration where sediment was removed from the basin, then used to fill in a shallow drainage ditch at the bottom of the picture.

This is the same wetland from above.

The goal for this wetland was to restore it back to a seasonal depression. Not long after the earthwork was done, an August rain partially filled the basin with fresh water.  These Type I & II wetlands are crucial for waterfowl during the nesting season.

Other times, the source of drainage is below ground in the form of drain tile.  This contractor is removing the old cement drain tile with a backhoe.

These old cement tiles continue to work even after decades of being under ground. You can see the water trickling out of this broken tile even though it hadn't rained at this site for over 3 weeks.

At right, a core trench is being dug where an embankment will be built.  The core trench will help create a water tight seal. 

An embankment is basically an earthen dam that will hold back the water in the former drained wetland area. 

Here is an example of a finished embankment holding water in the restored wetland to the right.  The wetland was ditched from right to left near where you can see the electric pole.

Mulch was applied to the embankment to help control erosion while the vegetation becomes established.

This picture is showing the outlet of a restored wetland with a very large watershed.  Once the wetland fills up, the water will spill out over the metal wier and rock rip-rap.  The engineers designed it this way to keep the embankment from washing out.

Finally, all the patience, planning, and work will pay off.

This Blue-winged Teal and her brood are utilizing a Type II wetland that was restored the previous summer.