The Pool 2 Dredged Material Management Plan (DMMP) study area is located between Lock and Dam 2 near Hastings, Minnesota, and extends upstream to Lock and Dam 1, from river miles 815.2 to 847.7, respectively. The study area includes Upper Pool 2, which is situated in the urban area of Minneapolis and St. Paul.
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 authorized width and depth 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 2. This plan was initiated due increases in dredging volumes throughout Pool 2. Furthermore, three temporary dredged material placement sites need to be excavated in Lower Pool 2.
Pool 2 has been experiencing higher flows due to rainfall. As a result of more sediment, Pool 2 now requires additional dredging. Between 1981 and 2014, the average amount of material dredged per year in Pool 2 was approximately 107,000 cubic yards. The Corps’ September 2016 sediment assessment predicted future dredging requirements throughout Pool 2 to increase substantially, to approximately 169,000 cubic yards per year. Therefore, the 40-year target capacity for the Pool 2 DMMP is approximately 6.8 million cubic yards.
The DMMP is evaluating a list of potentially suitable sites to develop the Federal Standard or Base Plan for managing dredged material over the next 40 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).
In fiscal year 2018 planning continued in an effort to identify the Tentatively Selected Plan (TSP) for the Pool 2 DMMP that would meet the Federal Standard.
In spring 2019, the Corps will hold a public meeting to inform the local communities of the navigation mission, the federal acquisition process, and the Corps’ desire to identify willing sellers for the possibility of permanent upland placement of dredge material. The Corps will continue to engage federal and state partners and other stakeholders.
The draft report with the TSP will be released to the public for a 30 to 60 day review in May 2019. The Corps will evaluate and consider all public comments for the final DMMP. A final plan and subsequent real estate acquisition are anticipated to begin in fiscal year 2019.
Congress authorized the Upper Mississippi River 9-Foot Channel Navigation Project via the River and Harbor Act of 1930.