City raises concerns on bridge construction
The city of Hastings officially submitted the bridge type it would like to see built here, expressed concerns about flooding during construction, and raised other issues in its comments on the environmental assessment (EA) for the Hastings bridge replacement project.
The cable-supported bridge is the option the city feels would best fit Hastings' legacy as a river town. In its written comments on the EA, the city cites the Spiral Bridge as being the only one of its kind in the state, and the current bridge as the first of its kind to be built in Minnesota.
"As a significant river city, it is imperative another legacy bridge is constructed in Hastings and a cable-supported bridge would continue that legacy as the first of its kind in the state of Minnesota built to carry vehicular traffic," the comments state.
The city also expressed its opposition to having a concrete box girder bridge built because of its prevalence in the state, year longer construction period than the other two options being considered (cable bridge and arch bridge), and the steeper grade that'd be required due to the supports below the bride deck.
"This type of bridge has risen to ubiquity in the state of Minnesota, thereby impairing its ability to be distinctive or groundbreaking," the comments state.
The city also feels the EA is incomplete in regard to contingency plans for flooding during construction, especially in the staging area the contractor will use to house construction materials and machinery (a portion of flat land along the river northwest of the public boat launch in Jaycee Park).
"Past experience would suggest the likelihood for flooding in that area, along with others near the Mississippi River, (which) would require alternative staging areas during the course of the construction period. Flooding potential bears significant consideration for contingency planning," the comments state.
Steve Kordosky, the MnDOT project manager for the bridge replacement, said the onus will be on the design-build contractor to assess the flood risk and make an evacuation plan for the materials and machinery that will be stored at the staging area.
He said the contractor may look at flood data and consider laying down several feet of gravel fill for the materials and machinery to sit on top of.
The new bridge will have anti-icing technology built into it, and there needs to be a facility somewhere near the bridge to house the machinery that runs it. The city said it's opposed to having the anti-icing facility on the south side of the bridge in the downtown area due to the area's historic nature.
The city's preference is to build the anti-icing facility into one of the embankments on the north side of the bridge so it's out of view from the road.
Kordosky said MnDOT will agree to build the facility on the north side of the bridge, but won't build it into the ground because of the added cost related to doing so.
From the city's standpoint, the same goes for any storm water treatment features or ponding basins, it doesn't want to see them on the south side of the bridge.
Kordosky said MnDOT is working with the Minnesota Pollution Control Agency to make sure any ponding basins or storm water treatment features are below ground on the north side of the bridge.
The physical sensitivity of the buildings downtown is also addressed in the city's comments.
"MnDOT must be especially sensitive to the needs of the historical buildings in the area near downtown, and in particular the City Hall building as it relates to vibration, blasting and any construction activities that would have an impact on the facilities," the comments state.
The city says it understands the location and magnitude of construction vibrations can't be fully assessed until the final design phase of the project, but stresses that good communication is a must between MnDOT and any property owners who may be effected by vibrations.