Great Island Bridge No. 499 Replacement

Client: RIDOT

Construction Cost: $8.5M

Key Facts:

  • Structural Engineering
  • Maintenance of Traffic
  • Environmental

Originally constructed in 1959, Great Island Bridge No. 499 (top right) served as the sole means of access for the residential community of Great Island, spanning the tidal waters of Point Judith Pond between Bluff Hill Cove and the Port of Galilee. Due to its advanced age, condition, and substandard geometry, the RIDOT identified Great Island Bridge for full replacement.

The new bridge (completed in 2016) is a 3-span structure consisting of two, 57-foot end spans and an 86-foot center span, for a total length of 200 feet. The center span increases the clear channel opening from 25 feet to 76 feet. The cross section of the bridge is 48’-6” wide and provides for a 30-foot roadway, two 7’-6” reinforced concrete sidewalks, granite curbing, vehicular rail, pedestrian rail, and decorative lighting on both sides of the bridge, all supported by seven pre-stressed concrete box girders.

The substructure consists of two, short reinforced concrete abutments supported on micro-piles and two intermediate piers. The piers consist of reinforced concrete caps supported by steel H-piles driven to bedrock and caped by 30-inch diameter steel pipe pile jackets filled with concrete.

In order to maintain access to the island, a staged construction process was utilized. This process involved removing approximately half of the existing bridge while traffic was maintained on the remaining half.  During construction, traffic was maintained using a one-lane, alternating-flow roadway regulated by temporary traffic signals. A portion of the new structure was constructed adjacent to the remaining section of the existing bridge. Upon completion of this portion, traffic was redirected onto the new structure while the remainder of the existing bridge was removed and construction was completed.

Final design and permitting were completed in 2014. The project was constructed at a cost of $8,538,000 between 2014 and 2016.


2018 ACEC Engineering Excellence Award