BONNER, Mont. (AP) Montana highway officials are working on plans for a new interstate highway bridge over the Blackfoot River — even though there’s no money for a new bridge yet.
Montana Department of Transportation officials aim to replace the Interstate 90 bridge and remove the piers in the river, The Missoulian reported.
“We don’t have any funding identified for it, but we really want to get to the environmental phase because we have to do that regardless,’’ said Ed Toavs, MDT’s Missoula district administrator. “Once we do that and get a preliminary design in the environmental document, that allows us in the future when funding does become available, to really start working on the specific bridge design and then construct it.’’
The MDT held its first open house on the project Oct. 30, even though the state is at least five years from the construction phase.
Built in the 1960s, the current I-90 bridge stands on piers that block the middle of the channel, causing a safety concerns for recreational floaters.
Interstate 90 bridges eastbound and westbound are two of five that span the Blackfoot within a half-mile of its mouth. The other three — a pedestrian bridge, the Montana state Route 200 span and a Montana Rail Link trestle — are supported by piers and abutments on either side of the river. Only the I-90 piers block the middle of a channel that was narrowed significantly when Milltown Dam was removed in 2008.
Until this summer, the fish and wildlife division of Montana Fish, Wildlife and Parks had kept the stretch closed to river traffic altogether for fear the hydraulics around the piers could cause entrapment issues. The ban was lifted July 1 but will be reinstated for future Mays and Junes.
“The department as a whole is definitely supportive of addressing the pier issue,’’ said Chet Crowser, Region 2 parks manager of the FWP. “For a long time now, there’s been a fair amount of discussion amongst the local community here about the piers and safety issues and what we can do to address those.’’
The obstructing piers also show signs of scouring around the base, Toavs said.
Bridge inspections have not found anything deficient on either interstate bridge.
“They’re in good shape that way,’’ Toavs said.
The MDT envisions two new bridges in the same places and on the same alignments. The river is now narrow enough to be easily spanned by a two-lane freeway bridge without a pier in the middle.
“I don’t anticipate an exotic design,’’ Toavs said. “It’s something that’s very common and doable.’’