BROADWAY BRIDGE

DEMOLITION, ENGINEERING, STRUCTURAL SOLUTIONS

JC Constructors RELOCATED THE BOISE RIVER TWICE, DEMOLISHED THE EXISTING 60 YEAR OLD BRIDGE, AND CONSTRUCTED A 104’ CONCRETE DECK WITH BELVEDERE SIDEWALKS.

JCC completed this project on an aggressive schedule that required removing and replacing the existing Broadway Avenue (Hwy 20) bridge over the Boise River in downtown Boise in eight months and on schedule for the Boise State Broncos season opener football game. The project included relocating the Boise River twice, demolishing and removing the existing 60 year old four lane concrete bridge, driving 170 pile, construction of five cast-in-place concrete piers, placing ten steel girders that were each 420’ long, and constructing a 104’ wide concrete deck with belvedere sidewalks. The bridge costs are $5M.

The project’s formal deadline was the BSU football team’s home opener on Labor Day Weekend. That deadline followed its football driven start date of January 2nd, after the previous late December’s Bowl Game hosted at BSU’s stadium. The project also had an unspoken milestone date. The In-River work would be extremely difficult after the Boise River flows increased, typically in early to mid-April. JCC crews started work started immediately on Day One to reroute the Boise River to allow demolition without dropping debris into the water below. Demolition of the first segments of the old bridge went quickly, and two of the three In-River pile supported piers were underway and excavated soon after. Pile caps were complete within five weeks, and the river was again in the way and JCC was rerouting it once again. This allowed the completion of the demolition and excavation for the third In-River pier. And last, JCC got the excavation for both abutments under way. By the end of February, all foundations were complete and all the piers and abutments were beginning to rise. 140’ girders were ready to ship in mid-March and the up-river reservoirs were filling quickly. JCC set the last of thirty girders in early April while other JCC crews were pulling the river cofferdams out of the fast-rising Boise River.

Work then moved up onto the large 105’ x 420’ bridge deck, steadily progressing above the very active river below. The entire girder system needed to be torqued, needed to be decked, needed overhangs constructed. The overhangs included six large belvedere sidewalk turnouts and formed corbels underneath at 3’ on center the entire length on both sides of the bridge. Several months of preparation, into the summer. Meanwhile, two bike tunnels were being built, 30’ x 130’ each at both ends of the bridge, a significant effort by JCC crews. In all, the bridge and tunnel decks measured 60,000 SF when completed. Finally, JCC fabricated, galvanized and installed very ornate steel traffic railings. The Broadway bridge was put in service as a new, very appealing pedestrian, bike and traffic friendly ‘City Showcase’ passage over the Boise River in time for BSU’s home opener.

JC Constructors has completed demolition of environmentally sensative materials such as concrete, asebestos, and lead paint around clear waters, habitats for threatened and endangered species, and other environmentally sensitive areas.
Dewatering is necessary for nearly all of JCC's construction projects. Water and site conditions vary significantly, so JCC uses a variety of systems for each site's individual dewatering needs. These systems have allowed JCC to effectively dewater significant bodies of water, such as rivers, lakes, and streams, as well as deep excavations in areas of high groundwater.
JCC employs an extremely skilled team of men producing very complicated, often corrosion resistant metal fabrications. From pressure piping manifolds to ascending radial stairs to large fabricated lids, the JCC fabrication team has been able to support almost any fabricated project requirement.