Tennessee Department of Transportation (TDOT) officials said Friday that widening the road up to Signal Mountain or reworking the W Road would both be very costly. Officials said spot improvements on the existing road should solve most of the issues and be much less expensive.
TDOT officials made a presentation on the status of Signal Mountain Road to the town council and interested residents.
What is being done now about the three-mile road going up the mountain, and longer range plans were shown.
What has and is being done now is considered to be maintenance. This involves regular monitoring for problems and clearing drainage ditches, which must be done often because they are narrow. If water flow is blocked, it is diverted across and into the road, which is the cause of most of the deterioration. The road was repaved in 2011 with a life expectancy of 12 years, but water penetrates the slope causing cracks and the asphalt to settle requiring regular patching. Vegetation control is done regularly, including herbicides, mowing and tree cutting. This road is at the top of the list to monitor when snow is predicted, the council was told.
There are maintenance challenges that must be considered when working on this road, including minimal working room. For the protection of TDOT workers, lanes are closed when maintenance is being performed, and this causes frustration with drivers.
There are also geo-technical challenges such as falling rock. The biggest problem is the steep slope on the low side of the road. When cracks or sinking is first noticed, drilling is done in the area to see what is under the road there. The cracks are monitored and smoothed to keep water out. When the ditches cannot hold all the water, it causes failures in the pavement such as the cracks, but TDOT officials said it is still safe. Where the road collapsed in 2008 was right below a waterfall. TDOT is aware of the problems and is working to fix them even though workers might not be visible to the cars, officials said. It is cheaper to keep the road in good condition with maintenance rather than replacing it, the council was told.
In an attempt to reduce drivers' frustrations, TDOT asked to improve communications with the town for help in monitoring and other concerns involving the road. TDOT will tell the town when they will be working and the length of time workers will be present. City Manager Boyd Veal said he would coordinate the information with other communities on the mountain. TDOT needs to know, for example, when the W Road will be closed so that planned maintenance on Signal Mountain Road can take place.
A technical report on the road was done in 2011 from Suck Creek Road to Palisades Road and has recently been updated. The new data show that the road is still functioning as it should and is not over capacity. Crash data shows that it is the same as the state average, showing that there are no safety issues.
The future of the road has been looked at using three scenarios. It could be improved by adding lanes. If this was done, it would require widening the shoulders and adding a catchment area for falling rock, which would have a large environmental impact. Another method to contain falling rock could be to bolt wire mesh to the rock faces. The negative impact of this plan would be that the road would be completely closed for two years and partially closed for another six months. The estimated cost for this plan, when it was originally done in 2012, was $25 million per mile totaling $75 million for the three-mile stretch.
Another scenario considered at the same time was to build an alternate route up the mountain. The length of this road would be 6.2 miles, over twice as long as Signal Mountain Road, and would be twice the travel time. The positive with this plan is that the road up the front of the mountain would remain open during the work. The new road would be built in the location of the W Road and would have a substantial environmental impact. Another problem is that the W Road is considered to be historical. The cost of this project was projected to be $114 million in 2012. After the new road would become functional, the old road would be given to the municipalities where it is located and they would be responsible for maintaining it.
The third method considered for keeping the road functional would be to make spot improvements. This option would have cost $10.2 million in 2012, when the plan was done. This would involve improvements to the problem areas as TDOT becomes aware of them. It also would include improving the drainage ditches. This is expensive and time consuming because a lot of utilities are buried in the ditch lines and would have to be re-located. TDOT has an agreement that utilities are responsible for moving their equipment; however, the huge cost could bankrupt some
small utility companies so TDOT shares the cost. It was noted that no matter which option of working on the road, the utility lines would be impacted. Spot improvements would take approximately 12-18 months to complete.
TDOT officials said they feel that spot improvements would take care of capacity and would fix the majority of issues facing Signal Mountain Road, and this plan is what the community is looking for.
Paul Degges, deputy commissioner and chief engineer for TDOT, said that the Tennessee General Assembly has approved about $10.5 billion for roads. TDOT will get about $2 billion each year. There are 962 road projects on the list to be done. It is believed that they can all be finished in 10-14 years. Signal Mountain is not the first on the list. The steps needed for road building are planning studies, which is the preliminary plans that were created in 2012. The next step is an environmental impact study that takes 12-18 months. Another option includes doing nothing, said Mr. Degges. Then the design phase is followed by the engineering phase before construction begins. A major project takes about 12 years from start to finish, he said.
This project is on the list of 962. The environmental study has already been funded and, if that phase is started next year, Signal Mountain Road would get in the queue. Mr. Degges recommended that a representative from Signal Mountain meet with leadership at TDOT yearly to remind them this project is important to the town.
This presentation will be available to view on the town’s website.