Pool 10 Dredged Material Management Plan – Allamakee & Clayton County, Iowa, and Crawford & Grant County, Wisconsin

U.S. Army Corps of Engineers, St. Paul District
Published March 17, 2021
Updated: March 29, 2022
Location

The Pool 10 Dredged Material Management Plan (DMMP) study area is located between Lock and Dam 9 near Lynxville, Wisconsin, and Lock and Dam 10 at Guttenberg, Iowa, spanning nearly 33 river miles from 615.1 to 648.0. The study area includes several communities Lower Pool 10 – McMillan Island near Guttenberg, Iowa – 2010near the main navigation channel including Prairie du Chien, Wisconsin, and Guttenberg, Iowa.

Description

The U.S. Army Corps of Engineers operates and maintains the Upper Mississippi River 9-Foot Channel Navigation 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 10. This plan was initiated due to needs for dredged material management upland placement sites, especially in the downstream reach of the pool.

There are nine historic dredge cuts in Pool 10. Of those nine, five are considered active with three of those five requiring dredging on a nearly annual basis in the downstream end of the pool. Since 1981, the average amount of material dredged per year in Pool 10 is approximately 27,000 cubic yards, however in the past decade that has increased to nearly 40,000 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 2021, the Corps began drafting the Tentatively Selected Plan (TSP) for the Pool 10 DMMP. The Corps obtained feedback from affected stakeholders, including via 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. The process of identifying appropriate sites and writing the draft report is expected to run through fiscal year 2023.

In fiscal year 2024, the Corps will release a draft report with the TSP sites identified for public review. 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 is anticipated to begin in fiscal year 2025 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.

Expended to date:                                      $286,745.88