US Army Corps of Engineers
St. Paul District

Projects

Dredged Material Management Plan (DMMP): Pool 9

Published March 15, 2018
Updated: March 21, 2019
Location

The Pool 9 Dredged Material Management Plan (DMMP) study area is located between Lock and Dam 8 at Genoa, Wisconsin and Lock and Dam 9 near Lynxville, Wisconsin spanning more than 31 river miles from 679.2 to 648.0.  The study area includes several communities near the main navigation channel including Lansing, Iowa and De Soto, Wisconsin.

Description

The U.S. Army Corps of Engineers operates and maintains the Upper Mississippi River 9-Foot Navigation Channel Project, and one method the Corps uses to keep the channel the right size is dredging river soils or “material.”

The purpose of the DMMP is to prepare a coordinated long-term plan for managing dredged material in Pool 9.  This plan was initiated due to needs for dredged material management upland placement sites, especially in the upstream reach of the pool.

There are seven historic dredge cuts in Pool 9.  Of those seven, four are considered active with two of those four requiring dredging on an annual basis.  Since 1981, the average amount of material dredged per year in Pool 9 is approximately 55,000 cubic yards.

The DMMP is evaluating a list of potentially suitable sites to develop the Federal Standard or Base Plan for managing dredged material for a minimum of 20 years.  The Federal Standard is defined as “the dredged material disposal alternative or alternatives identified by the Corps which represent the least costly alternatives consistent with sound engineering practices and meeting the environmental standards established by the [Clean Water Act’s] 404(b)(1) evaluation process…” (33 CFR 335.7).

Status

In fiscal year 2018, the Corps began drafting the Tentatively Selected Plan (TSP) for the Pool 9 DMMP that will be the least costly, operationally feasible, and environmentally acceptable alternative.

In fiscal year 2019, the Corps will continue to draft the TSP and obtain feedback from affected stakeholders, including a public meeting to inform local communities of the navigation mission, federal acquisition process, and the Corps’ desire to identify willing sellers for the possibility of permanent upland placement of dredge material.

In fiscal year 2020, the Corps will release a draft report with the TSP sites identified for a public review period.  The Corps will evaluate and consider all alternatives identified in the public comments for the final DMMP. 

A final plan and subsequent real estate acquisition are anticipated to begin in fiscal year 2020 or 2021 and will be phased over time, pending prioritization of parcels and availability of funds.

Authority

Congress authorized the Upper Mississippi River 9-Foot Channel Navigation project via the Rivers and Harbors Acts of 1930 and 1932.