I-91 Rockingham Bridges

Constructed in the 1960s, Interstate 91 is New England’s north-south backbone. Near Rockingham, it crosses the Williams River and the Green Mountain Railroad on the “High Bridges.” Fifty years of service, heavy traffic and 6 months of deicing annually wore on the structures. Combined with undersized and fracture critical gusset plates, VTrans faced a costly renovation to temporarily extend their service life or replace the bridges.

The new, $50 million I-91 Rockingham Bridges are the state’s first four-span spliced precast concrete girder structure and are the last of three major I-91 bridge replacements in southeastern Vermont. The design-build project uses one-of-a-kind elements and some of Vermont’s largest precast segments, to expedite and simplify construction while overcoming a unique unbalanced layout.