The U.S. Army Corps of Engineers, St. Paul District, is currently exploring options to continue its maintenance requirements of the 9-foot navigation channel. This channel includes the Mississippi River, from Minneapolis to the district's southern boundary at Lock and Dam 10, in Guttenberg, Iowa, as well as small portions of the Minnesota, St. Croix and Black rivers. 

Part of the maintenance effort includes finding permanent, suitable locations to place material removed from the channel. Doing so ensures navigation vessels can safely move bulk cargo to ports within the United States and beyond. St. Paul District staff are in the process of looking at a variety of options in various locations along the Mississippi River to place dredged material. The purpose of these dredged material management plans, or DMMPs, is to prepare a coordinated, long-term plan for managing dredged material. 

These plans were initiated because permanent placement sites previously used along the Mississippi River have reached capacity. In addition, existing island transfer sites have a limited capacity. Dredged material placed at island transfer sites will need to be offloaded to permanent sites. Therefore, additional permanent sites are needed to accommodate the Corps’ dredging needs. 

Costs associated with managing the dredged material have increased significantly during the past 20 years, so the plans will also look for ways to reduce the costs to tax payers.

In order to maintain the 9-foot navigation channel, material that settles in the channel area must be removed. Dredging is a method for removing that material. This material is placed in designated areas along the river. Some of these areas are beneficial use placement areas.

Beneficial use of dredged material is the productive use of the material by the public or private sectors. Examples of common beneficial uses of dredged material in the St. Paul District are upland habitat development, wetland creation, aquatic habitat enhancement, creation of areas for bird nesting, beach nourishment, winter road maintenance, levee repair and improvement, aggregate for concrete, bank protection and general purpose fill.

As a result of the Great River Environmental Action Team, or GREAT, study completed in 1980, Blackhawk Park was selected as one of the designated dredge material placement sites in Pool 9. Utilization of Blackhawk Park as a placement site reduced transport distance and subsequently the cost of hydraulic and mechanical dredging, while providing an opportunity to rehabilitate and enhance existing recreational facilities.

For more information on the St. Paul District dredged material beneficial use sites, click here.