US Army Corps of Engineers
St. Paul District

Navigation projects, studies and information papers

Dam Bridge & Gate Painting – Lower St. Anthony Falls through Lock and Dam 10

The St. Paul District operates and maintains 13 locks and dams from Upper St. Anthony Falls in downtown Minneapolis, Minnesota, to Lock and Dam 10 in Guttenberg, Iowa. Each lock and dam is a critical step in the "stairway of water" that makes navigation possible between Minneapolis and St. Louis, Missouri. These facilities are aging structures, with locks and dams 2 through 10 originally constructed in the 1930s. These sites include a dam bridge and varying numbers of dam gates. The moveable dam gates are one of the most critical system components because they control pool elevation for navigation, flood control and environmental purposes.
Published: 2/26/2015

Disposition Study, Lower St. Anthony Falls Lock and Dam, and Lock and Dam 1, Upper Mississippi

A Section 216 study will investigate the appropriate future disposition of Lower St. Anthony Falls (LSAF) Lock and Dam and Lock and Dam 1, located on the Mississippi River in Minneapolis, Minnesota. The LSAF Lock and Dam was constructed as part of the Minneapolis Upper Harbor project in 1956 as authorized by the Rivers and Harbors Act of 1937. Lock and Dam 1 was originally constructed in 1917 and was modified in 1932 under the authority of the River and Harbor Act of 1930. The U.S. Army Corps of Engineers operates and maintains the two sites. Both locks have been affected by the decrease in the demand for navigation services stemming from the closure of Upper St. Anthony Falls Lock and Dam on June 9, 2015. This disposition study will examine the benefits and costs of continuing to operate LSAF and Lock and Dam 1.
Published: 3/22/2019

Disposition Study, Upper St. Anthony Falls and Lock and Dam, Upper Mississippi River

A Section 216 study will investigate the appropriate future disposition of Upper St. Anthony Falls Lock and Dam, or USAF, located in Minneapolis, Minnesota. The USAF was constructed as part of the Minneapolis Upper Harbor project in 1963 as authorized by the Rivers and Harbors Act of 1937. Congress closed USAF to navigation on June 9, 2015, under Section 2010 of the Water Resources Reform and Development Act of 2014. The U.S. Army Corps of Engineers continues to operate USAF for flood damage mitigation. The disposition study will examine the benefits and costs of continuing to operate USAF.
Published: 3/14/2016

Dredged Material Management Plan (DMMP): Lower Pool 4

The Lower Pool 4 Dredged Material Management Plan (DMMP) study area is located between Lock and Dam 4 and the foot of Lake Pepin, river miles 753.0 to 764.0. The purpose of the DMMP is to prepare, a coordinated long-term plan for managing dredged material in Lower Pool 4 of the Upper Mississippi River for the purposes of continued operation and maintenance of the Upper Mississippi River 9-Foot Navigation Channel Project.
Published: 3/15/2018

Dredged Material Management Plan (DMMP): Pool 2

The Pool 2 Dredged Material Management Plan (DMMP) study area is located between Lock and Dam 2 near Hastings, MN and extends upstream to Lock and Dam 1, river miles 815.2 to 847.7. The purpose of the DMMP is to prepare a coordinated long-term plan for managing dredged material in Upper and Lower Pool 2 of the Upper Mississippi River for the purposes of continued operation and maintenance of the Upper Mississippi River 9-Foot Channel Navigation Project.
Published: 3/15/2018

Dredged Material Management Plan (DMMP): Pool 5

The Pool 5 Dredged Material Management Plan (DMMP) study area is located between Lock and Dam 4 at Alma, Wisconsin, and Lock and Dam 5 near Minneiska, Minnesota, spanning nearly 15 river miles from 752.8 to 738.1. The purpose of the DMMP is to prepare a coordinated long-term plan for managing dredged material in Lower Pool 5 of the Upper Mississippi River for the purposes of continued operation and maintenance of the Upper Mississippi River 9-Foot Channel Navigation Project.
Published: 3/15/2018

Dredged Material Management Plan (DMMP): Pool 6

The Pool 6 Dredged Material Management Plan (DMMP) study area is located between Lock and Dam 5A at river mile 728.5 and Lock and Dam 6 at river mile 714.1. The purpose of the DMMP is to prepare a coordinated long-term plan for managing dredged material in Pool 6 of the Upper Mississippi River for the purposes of continued operation and maintenance of the Upper Mississippi River 9-Foot Channel Navigation Project.
Published: 3/15/2018

Dredged Material Management Plan (DMMP): Pool 9

The Pool 9 Dredged Material Management Plan (DMMP) study area is located between Lock and Dam 8 at Genoa, Wisconins, and Lock and Dam 9 near Lynxville, Wisconsin, spanning more than 31 river miles from 679.2 to 648.0. The purpose of the DMMP is to prepare, a coordinated long-term plan for managing dredged material in Pool 9 of the Upper Mississippi River for the purposes of continued operation and maintenance of the Upper Mississippi River 9-Foot Channel Navigation Project.
Published: 3/15/2018

Level of Service Reduction at the Twin Cities Locks and Dams

Constrained funding and the Nation’s fiscal deficit have led to reduced operations and maintenance funding within the Corps Inland Marine Transportation System (IMTS). When coupled with deteriorating infrastructure and increasing costs of operation, it became clear that the level of service the Corps has been providing at some locks and dams is not sustainable.
Published: 2/27/2015

Lower Pool 2 Channel Management Study

Pool 2 is the navigation pool created by the construction of Lock and Dam 2 at Hastings, Minnesota, at river mile 815.2. The pool is approximately 32.4 miles long and stretches upstream to Lock and Dam 1 in Minneapolis at river mile 847.6 (often referred to as the Ford Dam). Between river miles 818 and 820, the navigation channel switches from one bank of the river to the other and back again creating a near 90-degree bend in the river at mile 819.
Published: 2/27/2015

Mississippi River 9-Foot Project Channel Maintenance

The U.S. Army Corps of Engineers, St. Paul District is responsible for maintaining 244 miles of the Upper Mississippi River 9-foot channel navigation system from the head of navigation at Minneapolis, Minnesota, to Guttenberg, Iowa. The navigation system also includes the lower navigable portions of the Minnesota, St. Croix, and Black Rivers.
Published: 2/26/2015

Mississippi River 9-Foot Project, Locks and Dams

The St. Paul District is responsible for maintaining 244 miles of the Upper Mississippi River 9-foot channel navigation system from the head of navigation in Minneapolis, Minnesota, to Guttenberg, Iowa. The project is located in or contiguous to Minnesota, Wisconsin and Iowa. The navigation project within the St. Paul District includes 13 sets of locks and dams that are operated and maintained by the U.S. Army Corps of Engineers. In addition to the locks and dams the project includes channel maintenance, recreation and natural resource activities.
Published: 2/27/2015

Mississippi River Lock and Dam 5A Embankment and Levee Certification

The Lock and Dam 5A embankment is located along the Mississippi River about 3.5 river miles above Winona, Minnesota, and about 3 river miles below Fountain City, Wis. FEMA is verifying that all levees recognized as providing protection from the base flood meet the requirements outlined in 44 CFR 65.10. This code requires that specific structural requirements must be certified by a registered professional engineer or a federal agency with responsibility for levee design. The City of Winona is performing this certification for the flood risk management project with the Corps providing an analysis of the Lock and Dam 5A embankment in support of that certification.
Published: 10/1/2018

Mississippi River Locks and Dams 2–10 Embankment Rehabilitation Adjacent to Structures

Earthfill embankments are integral to each of the Mississippi River Locks and Dams 2 through 10. The purpose of this project is to reestablish and armor degraded embankments to prevent further erosion and potential failure during high water events. The existing rock protection is well past its intended design life and does not perform satisfactorily. Wave action from high water causes continued widespread erosion.
Published: 2/26/2015

Mississippi River Locks and Dams 2–10 Guidewall Crib Repairs

Guidewalls are integral to each of the Mississippi River Locks and Dams 2 through 10. Guidewalls are long extensions of the lock walls, in either the upstream or downstream direction, that are parallel to the lock wall. These walls serve primarily to guide the long tows into the lock and to provide mooring facilities for tows too long to be accommodated in a single lockage. The guidewalls are constructed of multiple 35 to 40 feet length concrete monoliths with rock filled timber cribs beneath and behind them.
Published: 10/2/2015

Mississippi River Locks and Dams 2–10 Guidewall End Cell

Guidewalls are integral to each of the Mississippi River Locks and Dams 2 through 10. Guidewalls are long extensions of the lock walls, in either the upstream or downstream direction, that are parallel to the lock wall. These walls serve primarily to guide the long tows into the lock and to provide mooring facilities for tows too long to be accommodated in a single lockage.
Published: 3/16/2017

Mississippi River Locks and Dams 2–10 Miter Gate Replacements

Miter gates are integral to Mississippi River Locks and Dams, 2 through 10. Miter gates are comprised of two leaves that provide a closure at one end of a lock. Locks and Dams 2 through 10 have utilized the same miter gates since their inception. Over time, distress has been observed and has led to serviceability and safety issues. The purpose of this project is to restore the gates, increasing longevity and operational readiness, while decreasing repair costs and downtime due to maintenance of failure.
Published: 9/25/2017

Mississippi River Locks and Dams 2–10 Non-Structural Embankment Repair

Non-structural embankment repair projects at Locks and Dams 2 through 10 will address restoring embankments to meet current design standards. Most dam embankments are currently protected from the erosive forces of water by a layer of riprap placed along the embankment’s length. When the riprap eventually erodes, the embankment itself will erode if more protection is not added. The U.S. Army Corps of Engineers has designed and placed berms and small islands to assist in reducing wave action and wind fetch within pools created by the locks and dams. Reducing these forces increases the longevity of the embankment protections.
Published: 3/22/2019

Mississippi River Locks and Dams 2–10 Tow Haulage System Repairs

The tow haulage system is integral to the operation of each of the Mississippi River Locks and Dams 2 through 10. It is attached to the top of the lock and dam guidewall and helps guide tows through the lock chamber. The Lock and Dam 2 through 10 tow haulage system has been deteriorating over the past number of years. Two failures at Lock 7 identified the need for a project to address serviceability and safety issues.
Published: 3/14/2016

Mississippi River Locks and Dams 3–10 Sheet Pile Installation at Auxiliary Locks

Lock and Dams 3-10 have a partially completed auxiliary chamber with a single set of miter gates that may be used to pass shallow draft navigation traffic in the event the lock chamber was out of operation and the upstream and downstream pools were equalized. The Auxiliary Miter Gates are considered emergency gates originally intended to allow for limited navigation if the main lock became inoperable. Only one set of miter gates were installed. Since installation, the auxiliary emergency gates have never been used and the gate operating machinery was never installed.
Published: 9/12/2016

Small-Boat Harbor Dredging, St. Paul, Minnesota

The St. Paul Small-Boat Harbor is on the lower end of Harriet Island in St. Paul, Minnesota, at Upper Mississippi River mile 839.6 on the right descending bank. The length of the harbor is 2,375 feet; the width varies from 200 to 400 feet. The Corps of Engineers is authorized to maintain the harbor to a depth of 5.0 feet below low control pool elevation of 687.2 feet mean sea level (msl). The city of St. Paul is the non-Federal sponsor for the project and is required to furnish a suitable placement site for the dredged material.
Published: 10/2/2015

St. Croix River Project Channel Maintenance

The St. Paul District is authorized to maintain a 9-foot navigation channel on the St. Croix River from the mouth at the confluence with the Mississippi River near Prescott, Wisconsin, to river mile 24.5 near Stillwater, Minnesota. The authorized width is 200 feet. A 3-foot channel is authorized from river mile 24.5 to river mile 51.8 near Taylors Falls, Minnesota. The authorized width for this reach is 25 feet, and the controlling depth is 1 foot at extreme low water.
Published: 2/27/2015

Upper St. Anthony Falls Tainter Gate Rehabilitation

The Upper St. Anthony Falls Lock and Dam is part of the Inland Waterway Navigation System of the Upper Mississippi River Basin. The Tainter gate’s electrical control system has not been upgraded for many decades. Attempts to operate the gate have failed on various occasions and reliability is a concern. There is also question over the condition of the system’s hydraulics because the ram cylinder rooms and operating machinery rooms are constantly wet.
Published: 3/14/2016