The city would like to build a new tunnel on Wilcox Boulevard next to the current tunnel.
24 feet wide
9.6 feet tall
No bicycle path
41 feet wide
16.5 feet tall
5-foot pedestrian walkway
5-foot bicycle path
The city could embark within months on a $42 million dream of building a new tunnel through Missionary Ridge.
But the tunnel that could be created still solves only half the problem.
"Even though it's not optimal, it would be a heck of an improvement," said Lee Norris, deputy administrator for the city's Department of Public Works.
The City Council is expected to vote today on applying for a federal transportation grant that could provide up to $25 million to build a new tunnel next to the current Wilcox Tunnel on Wilcox Boulevard.
Norris said Public Works found out about the transportation grant a few weeks ago. City officials said the entire estimated cost of building the new tunnel would be $42 million.
The tunnel, if built, would provide two more lanes of traffic through Missionary Ridge for eastbound traffic. The existing tunnel would remain and be cut down to one lane of traffic for vehicles heading west toward Amnicola Highway.
Councilman Russell Gilbert, who represents the area, said neither he nor the community likes the idea of having just three lanes of traffic flowing east to west through the area.
"To me, it makes better sense to have four lanes," he said.
The existing tunnel has had problems with leakage from its ceiling and poor ventilation for years. The city patched up parts of the tunnel two years ago after problems occurred during the winter with water coming through the upper liner.
Since then, officials have spent months debating whether there should be another temporary patch or whether a more permanent solution is needed.
The Tennessee Department of Transportation is widening Shallowford Road from Wilcox Boulevard to state Highway 153 and much of the route is already four lanes.
File Photo by Dan Henry. Geotechnical engineers Scott LaSala and Bo Gao use a ground penetrating radar to survey the northeast wall of Chattanooga's Wilcox tunnel in this file photo.
Norris said the city eventually plans on widening Wilcox Boulevard to four lanes from Amnicola Highway to Shallowford Road.
"We desperately need another east-west route," Norris said.
Tom Richardson, project manager for Halcrow Group, said he is working as a consultant for the project and is offering guidance on tunnel design and development.
Even though the tunnel would be three lanes, it would be an improvement because firetrucks and buses cannot go through the existing tunnel, which is not tall enough for that type of traffic.
"We can raise the vertical to 14 feet," he said. "It's more than enough for buses."
But even taking out the existing two-foot sidewalk on the side of the current tunnel would not offer enough clearance for bus traffic, he said.
"It would be about as bad as it is now," he said.
Mark Heizner, a city engineer, said if the city gets the grant, construction would start in September 2013. The grant stipulates the tunnel would need to be built within three years, so the city could have a new tunnel under Missionary Ridge by 2016, he said.
Gilbert said he still questions whether parts of the current tunnel could be shaved enough to allow buses and firetrucks to get through.
But he also said he was not about to refuse money on the table for building an improved tunnel next door. Debate about the current tunnel could come later, he said.
"We need to go ahead and push for [the money]," he said.