Bethlehem, Connecticut bridge projects

Challenge

SLR is proud to have partnered with the Town of Bethlehem, Connecticut to perform design and construction inspection services for the replacement of Nonnewaug Road Bridge (State Project No. 10-88) and the preservation of the Magnolia Hill Road and Wood Creek Road Bridges (State Project No. 10-89).

All three bridges were funded under the CTDOT Federal Local Bridge Program. The existing 20-foot span stone abutment and concrete deck bridge at Nonnewaug Road was built in 1934. The existing bridge was narrow and out of alignment with the East Spring Brook channel resulting in scour at the abutments.

In addition to replacing the bridge, the Town was also interested in modifying the existing roadway alignment to reduce the sharp s-curve and improve safety.

Solution

SLR designed a 32-foot precast concrete arch on a new alignment which allowed Nonnewaug Road to remain open throughout most of the construction, a benefit to both the traveling public and the active farm operation adjacent to the bridge. With the bridge being highly visible to neighboring properties and the abutting farm being named after the existing bridge, special care was taken in selecting aesthetic treatments including a stone form liner, painted bridge rail, and timber guiderail on the approaches.

At Magnolia Hill Road and Wood Creek Road, SLR performed hands on inspections to identify existing deficiencies needing to be addressed under the FLBP Preservation Program.

At Magnolia Hills Road, this involved repairs to the concrete deck, installation of new membrane waterproofing, reconstruction of the existing curbs and installation of new bridge rail, construction of concrete end blocks, and installation of new guiderail on the approaches to bring the existing safety features up to current standards.

Early in the design process, SLR had noted insufficient drainage at the site was resulting in standing water on the bridge which was contributing to the deterioration of the bridge deck. In order to improve the longevity of the bridge repairs, the project also incorporated drainage improvements and the introduction of scuppers to the bridge itself.

At Wood Creek Road, a new waterproofing membrane was installed, the expansion bearings were replaced, and the existing steel girders sandblasted and repainted to protect against corrosion. Similar to Magnolia Hill, the curbs were reconstructed to allow for the installation of new bride rail, new end blocks were constructed, and the approach guiderail was replaced.

In addition to a hands-on inspection, SLR also coordinated concrete sampling of the deteriorated concrete of one of the existing abutments to inform the proposed repair design.

Impact

The work done on these two bridges addresses existing structural and safety deficiencies ad will extend their useful service life.