Moving forward with plans to increase storm water capacity along one of the city’s major roadways, Sherman recently voted to advertise bids for the construction of new culverts along Lamberth Road aimed at preventing the area for flooding during the most severe of storms.
The construction project, estimated to cost $1.7 million, will see the current 10-foot culvert replaced by four 12-foot box culverts, effectively quadrupling the area’s storm water capacity near Travis Street, Sherman Director of Engineering Clint Philpott said. Meanwhile, a smaller culvert near U.S. Highway 75 will also see improvements, effectively doubling its capacity to handle runoff.
“We are basically increasing the capacity of the drainage stream at the Post Oak Creek Crossing and Medical Center Crossing,”Philpott said. “That will allow a 100-year storm to pass without flooding.”
The project will also see a 1,100-foot section of the Lamberth between the two roadways raised by about four feet.
With the raising of the roadway, Philpott said the city plans to replace the asphalt surface with concrete, as is the city’s current standard for roadway construction. It made more sense to replace the full section of road with concrete than to create two different surfaces over a short distance, Philpott said.
Philpott described the primary intent of the project as to ensure road access during major storms, but added that it would also prevent some properties from flooding. During major storms, the road has been known to flood and has first responder access during these emergencies.
“With these improvements, the road won’t be inundated at all and the flow both up and down stream won’t be affected,” he said.
The city recently acquired two properties in the area that had been known for repeated flooding as a part of its mitigation efforts. One home was purchased using funds allocated by the Federal Emergency Management Agency for severe repeated flooding cases. The other was purchased using city funding, Philpott said, describing both homes as a 10- to 20-year flood risk.
The project will not create additional flow downstream and isn’t expected to increase the flood risk elsewhere downstream, Philpott said, noting that the city must ensure that will design of the project. Instead, it will allow storm water control to more efficiently and quickly handle storm water runoff.
The project comes as the city has been discussing options on how best to address future storm threats including the possibility of an $83 million detention pond project. In June, the city received an update on the city’s storm-water utility fund, which was created in 2017 as a funding source for future flood control projects.
Philpott described the current project as the largest project that will be financed through this fund. Depending on how favorable the bids come in, Philpott said the city could consider future projects in the near future, but did not give specific details on which are currently being considered.
Michael Hutchins is the local government reporter for the Herald Democrat. Contact him at firstname.lastname@example.org or @mhutchinsHD on Twitter.