The Idaho Transportation Department is considering two options to fix the ditches on the side of state Highway 75 in a construction zone south of Ketchum. One option would cost about $45,000, while the second would be closer to $1 million.
If the expensive option is chosen, it could mean sacrificing dedicated funds that ITD intends to use for construction of a new bridge across the Big Wood River near St. Luke’s Wood River hospital.
At a meeting of the Blaine County Regional Transportation Committee on Thursday, ITD officials said the ditches along the highway are more of a public perception issue than a safety issue. However, ITD District Engineer Devin Rigby acknowledged that if a vehicle runs off the road and into the ditch, a driver will have a better chance of recovering the vehicle rather than rolling it if the slope of the ditches is reduced.
“I still find it alarming the way some of our roads are being built, because they’re more dangerous than they were before.”
Blaine County commissioner
Rigby said he has received nearly a dozen letters or telephone calls from the public regarding concerns about the ditches.
Following road construction work in 2013, the ditches were left along the highway to retain storm water runoff, which Rigby explained to the committee is legally required so polluted water doesn’t run onto adjacent properties or into the Big Wood River. In the retention ditches, the water will either evaporate or drain into the soil.
Prior to construction, the sides of the highway were mainly flush with the roadbed.
“This is different from what we had before,” Rigby said. “The only way we get back to that is the million-dollar solution.”
ITD Project Development Engineer Walter Burnside said the $45,000 fix for the ditches would be to partially fill them and reduce the slope. The more expensive option is to build caps over the ditches and construct storm water trenches underneath, which would provide a relatively flat surface on the edges of the highway.
Burnside said ITD isn’t ready to make a decision regarding the ditches and will need to gather more information.
The construction zone includes a 3.75-mile section of highway from Timber Way just north of East Fork Road to the bridge near St. Luke’s. When finished, the highway will have two lanes in both directions.
The construction project, which will be resumed in the spring, is the first phase of a Highway 75 expansion plan. If fully funded, the plan will expand the size of the highway from Timmerman Junction to Ketchum.
The second construction phase would be replacement of the bridge near St. Luke’s to accommodate four lanes of traffic rather than the current two lanes. ITD officials have stated that the existing bridge is wide enough to accommodate three lanes of traffic, but local officials have stated that it will still cause a highway bottleneck once the first phase of construction is finished.
Burnside said building a new bridge is estimated to cost between $3 million and $4 million.
“Do whatever you can to make sure we have a four-lane bridge,” said former Sun Valley City Councilman and transportation committee member Nils Ribi.
“I think you’ve heard from this group that the bridge is very important,” said committee Chair and Blaine County Commissioner Angenie McCleary.
Blaine County Commissioner Larry Schoen is not a member of the committee but attended Thursday’s meeting to state his concerns about the ditches.
“The number of single-vehicle rollovers is startling alarming,” Schoen said. “Anything you can do to reduce the slope is a good solution. I still find it alarming the way some of our roads are being built, because they’re more dangerous than they were before.”