Poughkeepsie . . . Dutchess County Executive William R. Steinhaus announced the completion of emergency repairs to the bridge on County Route 43, DeGarmo Road, over Wappingers Creek in the Town of Poughkeepsie. The bridge is owned and maintained by the Dutchess County Department of Public Works.
In October, a routine bridge inspection performed by the New York State Department of Transportation found that the currents in the Wappingers Creek had severely undermined the north abutment of the bridge. According to Commissioner of Public Works Michael Murphy, “The discovery resulted in the NYSDOT’s issuance of a ‘Red Structural Flag’ warning, which requires the County to promptly repair the bridge or provide other corrective action. Because of the nature and severity of the problem, the bridge needed immediate repair or temporary closure.”
Steinhaus said, “County Route 43, DeGarmo Road, is a heavily used connector highway for passenger vehicles, public transportation, school buses, and commercial traffic between Route 55 and Route 44 between the Town of Poughkeepsie and LaGrange. Immediate closure of this bridge would have required long detours and caused major inconvenience to motorists not only between Poughkeepsie and LaGrange but also the thousands who use it has a north-south artery. Closing the major county connector would have been a nightmare to the residents of the county as well as the commercial business users. Certainly, a disaster would get more headlines, but in this case it’s a ‘good news story’ thanks to our terrific county staff.”
According to Greg Bentley, Director of Engineering, “Based upon the overall age and condition of the bridge, the County had previously requested federal funding for a future bridge replacement project. The traditional method of repairing the undermined bridge foundation, the red-flagged condition, would involve driving sheet piling which can only be accomplished after the bridge superstructure has been removed. Thus, the larger bridge replacement project would be required in order to address the structural red flag.” That project will not occur for several years and would be too late to address the worsening foundation problem.
DPW structural engineers teamed with Modjeski and Masters Consulting Engineers to produce an innovative design contract to repair the bridge foundation without removing the superstructure. The repair contract was assembled, advertised and let in just over one month. Bids were opened on November 13, 2006. The low bidder, A. Colarusso & Son, was awarded the contract one day later. Murphy said, “The work was completed in three days in the last week of November without ever closing the road or causing any significant inconvenience to the motoring public. The cost of the work was approximately $100,000 of county money.”
The work was performed from hanging scaffolds over the creek. Fiber reinforced polymer sheet piling was hand driven around the bridge abutment with minimal disturbance to the stream. Special underwater concrete was pumped beneath the structure through custom manufactured pipes, which accessed the void beneath the structure and were left in place. Work quality was assured through the use of an underwater camera. The bridge abutment was protected with large stone rip-rap to prevent future reoccurrence of the problem.
Director Bentley said, “The completed abutment repair allows the bridge to remain open and preserves the bridge foundation so that the larger bridge project can retain the existing abutments. The County now has the time to advance the bridge replacement project, thus providing federal and state funding for 80-95% of the bridge replacement cost.”
The County Executive concluded, “Everyday I am impressed and inspired by the innovative and creative effort of our county employees. This great success is just one more example of the high value taxpayers get from our dedicated county staff.”