Robert E. Lee & Associates, Inc. was selected to complete construction administration and observation of the CTH S Bridge replacement over the Ahnapee River. The project is being completed by Kewaunee County in conjunction with the City of Algoma and the Wisconsin Department of Transportation. The construction project measures 0.77 miles in length, and includes a bridge replacement, installation of retaining walls, storm sewer upgrades, concrete approach slabs, concrete curb and gutter and concrete sidewalk at an anticipated cost of $1.8 million.
Work began on July 1, 2019 and is on schedule for the November 8, 2019 completion date. Originally built in 1963, the steel pony truss bridge and its steel members were experiencing section loss and extensive rusting. A new dual span concrete slab bridge is being built and will include seal footings at both the pier and south abutment.
While the CTH S Bridge has a relatively small foot print, it includes some rather large complexities. The bridge structure needs to match into an existing retaining wall, which is attached to a large home. There is also underwater construction, environmental challenges and working on a navigable water way while maintaining boat traffic.
Pier seal footings have been poured using a technique of placing concrete with admixtures underwater and using the cofferdam as forms. Completing this work underwater has been challenging due to the irregularities in the bed rock within the river, but the contractor has successfully completed this work. Once the pier is completed the contractor will begin working on the north abutment using conventional steel piling to support the abutment.
This construction project has been great opportunity to continue REL’s relationships with Kewaunee County, City of Algoma, and WisDOT. Though challenging, the project team has been working well together to complete a successful project for the community.