Scope of Work:
Staged construction and reconstruction of the Route 9 Bridge over the Croton River. This project called for the widening of the existing structure, both left and right hand sides of the travel-way including abutment extensions and three pier extensions located within the waterway. This was accomplished by the construction of and then relocation of a temporary trestle placed parallel with the existing bridge. Temporary steel cofferdams were constructed at each pier to facilitate dewatering; excavation; pipe pile installation; and reinforced concrete pier extensions. The existing concrete deck and structural steel were removed, new pedestal installed and new structural steel installed. A new concrete deck was installed along with concrete barrier. Approach work involved concrete approach slabs; asphalt paving; concrete barrier installation; a gravity retained earth system was installed along a tidal marsh; a pedestrian/bicycle path was constructed parallel to the roadway with lighting and a timber pile; timber deck fishing platform was constructed. Constructability problems and relationship concerns with local environmental groups lead the New York State Department of Transportation to request ECCO III design and build a temporary trestle system which facilitated construction as well as addressed all environmental concerns.