Work slow now, but ready to roll on MN 36, in river
The St. Croix River Crossing bridge project and it’s components are set to roll out on track and under budget.
“Not a whole lot is happening right now, but we will start to move things along the roadway and in the river soon,” said project director Jon Chiglo of the state Department of Transportation.
The St. Croix River Crossing crew is preparing to start road construction on Minnesota 36 frontage roads. However, plans have changed a bit for how those projects will be handled. Frontage road construction will start on everything from east of Osgood Avenue and on the south frontage road from Club Tara to the Stagecoach Trail exit. Work west of Osgood Avenue and the Osgood-MN 36 intersection will start in 2014. Chiglo added that if this summer is dry, work could possibly be extended to the west.
“Completing the work east of Osgood limits the impact of one season and confines the work limits without extending the work that needs to be done.” Chiglo said.
The biggest traffic impact is expected to occur after July 4 when traffic on MN 36 goes down to one lane each direction, Chiglo said.
Barges have been put in the St. Croix River as of Monday as part of pier foundation work. The barges will serve as support vessels for the bridge project. About 40 flotillas made up of 120 barges will be in the river serving as material transport vehicles, and storing things such as cranes.
“Many of you are aware of the zebra mussels element that we dealt with. We’ve modified the process to correct the issue and put the barges back in the water,” Chiglo said.
A one-mile long no-wake zone will be implemented around the bridge pier work site in July and river patrols to enforce the no-wake rule will be increased. Chiglo said the no-wake zones is for safety, adding that swaying barges with the equipment on them could possibly problems.
Chiglo said he understands that creating the no-wake zone in July will not cause much impact on river boating traffic because project staff has been told that boat use on the river drops off in August.
“We’re hiring (Washington) county sheriffs to do enforcement on the river. Just like we hire state patrol to do safety inspections and work zone enforcement,” he said.
All five bridge pier foundations in the river should be in place by next summer, Chiglo said. A cofferdam will be constructed next week to help with pier foundation work, specifically pier 8. Cofferdams are an enclosure in the river that can be pumped out and allows crews to excavate the river bottom to help with foundation creation. Pier construction itself begins in July and runs through November. The longest drilled shafts for the piers are 135 to 140 feet long and will be secured with a rock socket.
“It’s like a root canal. You have to get a good hole to ensure the steadiness of the bridge and it really gets in there. But it’s more fun than a root canal,” Chiglo said.
Wind testing on a bridge model is being done in Toronto, which will determine how much wind stress the bridge can take. Other outside engineering companies are looking at the model to make sure it’s in top shape. Endangered mussels on the Minnesota and Wisconsin sides of the river must be relocated and work on pier 12 will only be allowed on the west side to prevent harming the mussels.
The next contract to be let will be for the superstructure portion of the bridge, with construction expected to begin in 2014 once the piers are in.
“The castings themselves (for the superstructure) will be trucked in or trained in and will go with the second contract of the bridge. It will be advertised in late July with letting in September or October and will be awarded at the end of the year,” Chiglo said. “Quite a bit of work will have to be done in off site facilities, and we’re hoping that the bidding in October will allow the contractor to set up facilities and work on the casting projects during the winter months.”
Work on the bridge will be done from 7 a.m. to dusk Monday through Saturday with an earlier end likely on Saturdays.
“There will be some night work as we get further into it like tying rebar that can be done without much impact to residents. But drilling will begin at 7 a.m.” Chiglo said.
The project is on track and under budget right now.
“There’s always something that can go wrong, but I’m extremely confident that we can construct this bridge and have it open by 2016,” he said.