Westbound span of Chain of Rocks Canal Bridge demolished

Interstate 270 was closed in both directions Tuesday, Feb. 3, 2015, between Riverview Boulevard in St. Louis and Illinois Route 3 as the westbound span of the obsolete Chain of Rocks Canal Bridge was demolished. The eastbound span was destroyed on Jan. 20. Photo by Christian Gooden, cgooden@post-dispatch.com

UPDATED at 12:45 p.m. with news of lane restrictions after today's blast

GRANITE CITY   •   Westbound Interstate 270 was open to traffic over the Chain of Rocks Canal on Wednesday but one eastbound lane remained closed after much of the obsolete canal bridge was demolished on Tuesday.

Demolition of the old truss bridge went off shortly after 10 a.m. Tuesday but Illinois Department of Transportation officials said a section of the old westbound span did not detonate as planned and another section caused minor damage to the new I-270 bridge as it fell. As a result, IDOT has called for another highway closure at 9:45 a.m. Wednesday.

Jeff Church of IDOT said the damage to the eastbound side of the new bridge — which is just to the north of the obsolete bridge that is being removed — was limited to a parapet. The damage did not undermine the structural integrity of the new bridge, he added.

IDOT officials hope to open all eastbound lanes in time for the Tuesday evening commute.

During the highway closure, westbound traffic was being diverted to Illinois Route 3 and eastbound traffic was being directed to exit at Riverview Boulevard in St. Louis. This is the second of three demolitions using explosives to remove the old canal bridges.

The bridge used to carry I-270 over the canal, but the bridge was replaced with a new span just to the north. Spectators have been permitted to watch the implosion from the Old Chain of Rocks Road canal bridge to the south.