Superior National Forest Bridge Repair

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This is a total small business set-aside under NAICS Code 237310, size standard $45M. The magnatude of this project is between $25,000 and $100,000.

The Cloquet River Bridge is located on Forest Road 122 in Township 56N, Range 12W, Section 25 (47.3099N, 91.7964W) in St Louis County MN. The Cloquet River Bridge constructed in 1957, is 67 years old two span continuous concrete beam bridge with a center pier.

Seasonal peak flow in the Cloquet River is typically between 1000-2000cfs. The June 18, 2024 Storm Event caused a peak flow of around 6000 cfs. The flooding appears to have overtopped road and bridge as the bridge deck was washed clean and there is debris on the road shoulder at bridge ends. There is major degradation and scour of the riverbed. There was a debris jam on the pier nose. A dive investigation found severe scour at the pier. The center pier footer is completely undermined for about 2/3 of it's length. (See attached undermining sketch.) It is assumed that the reinforced concrete superstructure (continuous over the pier) is currently supporting the pier from rotating into the scour hole. Without repairing the undermining prior to spring flows, it is feared the scour will increase and the bridge will collapse.

This project is intended stabilize the bridge until a replacement bridge can be funded, designed and constructed. The bridge is currently closed to all traffic and will remain closed to all traffic upon completion of the work