Thursday January 12, 2017
Embedded in the city council’s January 3rd consent agenda was an item that will ultimately help launch the Market Street reconstruction project, the awarding of the construction contract for the Market Street culvert replacement. This work is being completed separate from, but in anticipation of, the city’s larger effort to reconstruct Market Street and is being funded solely through the South Burlington Stormwater Utility, not through TIF dollars. The replacement is necessary in order for the project and City Center to meet their overall stormwater permit needs and will also reduce the risk for flooding along the road and adjacent areas.
According to a memo released by Public Works Director Justin Rabidoux and Deputy Director Tom DiPietro, the City of South Burlington held a bid opening for the Market Street Culvert Replacement Project in December, which includes replacement of the existing, undersized, corrugated metal pipe culvert with a 64-foot-long, 12-foot-wide, five-foot-tall precast concrete arch structure. Proposals from ten contractors were received ranging in cost from $662,756 to $1,047,042. The low bid in the amount of $662,756 from J. Hutchins, Inc. was chosen. This cost is below the amount approved in the stormwater utility’s budget for this project.
Rabidoux reported that the culvert is being replaced primarily because it is undersized by today’s standards and would represent a liability to the future of Market Street and City Center. “In today’s regulatory permitting environment we design culverts so that they can, at minimum, pass flow during a ‘25-year, 24-hour storm event,’ meaning it has to convey a storm that lasts for 24 hours and has the probability of occurring once every 25 years. This equates to just over four inches of rain in the 24-hour period,” Rabidoux said.
In addition, it has been determined that the culvert currently in place is smaller than the stream channel itself, and is therefore contributing to streambank erosion. It also does not allow for wildlife to pass under the street.
Some preliminary work may be done outside the roadway before the school year ends. After school ends, the project will begin in earnest and there may be times when portions of Market Street are closed. The street will be reopened with the new culvert by the start of the 2017-2018 school year.
SOURCE: Corey Burdick, Correspondent