MEDFORD- BRIDGE REHABILITATION, M-12-002, MAIN STREET (STATE ROUTE 38 S) OVER MYSTIC RIVER (AKA - CRADOCK BRIDGE)

This project consists primarily of (1) rehabilitation of the city-owned original stone masonry arch spans; (2) replacement of the Department of Conservation and Recreation (DCR)-owned bridge over the boat canal at the south end with a structural system consisting of butted pre-stressed concrete deck beams with a 5-inch topping slab or a cast-in-place concrete structural slab; (3) demolition of the DCR-owned west side widening superstructure of the bridge supported by a dam structure below (remnants of dam with tide gates that was removed in 1978); (4) replacement of the entire west side widening structure with a concrete arch system that replicates the dimensions of the stone arch structure; (5) rehabilitation of the river and canal walls immediately upstream and downstream from the bridge on the south side; and (6) strengthening or otherwise supporting the cantilevered slab over the power supply/transformer area for the old lock. Average daily traffic (2005) is 42,000. The roadway is classified as an Urban Minor Arterial. The proposed bridge typical roadway section (curb to curb width of approximately 50 feet including a 3 foot median and an 8-foot sidewalk on the east side and a 12-foot sidewalk on the west side) shall remain the same as existing. The existing bridge is a 100-foot long structure comprised of a 20-foot reinforced concrete beam structure constructed in 1908 and reconstructed in 1934 and an 80-foot twin stone-arch structure originally constructed in 1637 and reconstructed in 1880. Construction of the bridge will be completed in multiple stages to allow traffic during construction. The Mystic River is a navigable waterway from the Mystic Lakes in Winchester to Boston Harbor.