Input on a new study of Interstate 24 shows the most critical issue to respondents of the survey is congestion, TDOT officials said at an I-24 meeting in Chattanooga on Thursday.
The study showed that expanding roadway capacity by adding one lane in each direction throughout the state is needed. To do this through Chattanooga, the road would need to be double decked going around Moccasin Bend.
TDOT convened the public meeting concerning a study of the I-24 corridor between Chattanooga and Nashville.
The final phase of the 18-month study revealed concerns from people that actually use the road the most. As a contractor working for TDOT, the Atkins engineering and planning firm has been in charge of the study. Thursday night a consultant from that firm updated the public with a summary of information gleaned from the survey that 500 people participated in. The results will help identify the types of projects that will end up on the final list of the long term plan when it is finished in January.
An Interstate highway needs to function efficiently and safely for both passengers and the movement of freight, the consultant noted. I-24 is 185 miles in length and cuts the state of Tennessee in half, running from the Kentucky border and extending four miles into Georgia. Along the way, it crosses 10 counties and has an effect on 15.
Studies and models can fairly accurately project the future growth and needs of an area, it was stated. It has been projected that from 2010 to 2040, Hamilton County will have a population growth of 21 percent. In that same time frame, employment in the county is projected to increase 14 percent.
It is also recognized that the level of speed through Chattanooga currently needs improvement. The plans being formulated are meant to solve the current problems and also mitigate future ones. The planning process considers different types of projects which are evaluated then prioritizes them.
This phase of the project used a survey to identify perceived problems and collected solutions that were proposed by the participants. There were 31 types of projects that were recognized. About a third of these were addressed at the public meeting.
The creation of mass transit systems such as an express bus route or rail system was suggested. A commuter rail line would use existing rails and provide access from residential to downtown areas. A light rail system would require new tracks and stations to be built, would have more stops than a commuter line, therefore costing more to implement.
Improving ramps that enter and exit the Interstate by lengthening those that are short, were suggestions made on the survey. Also, alternate routes, which would be roads parallel to I-24, would relieve congestion in areas where needed. An example given was to direct trucks through a tunnel off of the Interstate, in areas where they are the cause of congestion.
Operational upgrades were also proposed, which would improve enforcement of things such as speeding and tailgating. This was especially a topic of concern for the area around Monteagle.
Increasing the efficiency of HOV lanes was another idea put forth. These could have extended hours or be open to single occupancy vehicles to relieve the congestion from downtown Nashville to Murfreesboro.
Improvements in signage and markings were requested. This could be done by adding warning lights and installing lane reflectors. Additional use of the intelligent transportation system was suggested, which would use more “dynamic message signs” that indicate approaching accidents or traveling time. Ramp metering is another means of improvement. When a vehicle turns onto a ramp, a green light directs the driver to enter the road. This method controls the cars getting onto an Interstate.
There were requests for new access points along I-24, although this seemingly was not an issue in Chattanooga. New interchanges and rest areas were specified as examples.
It was well documented that people fear driving alongside large trucks. Restrictions were proposed that would restrict trucks to only the right two lanes or in the case of the cut through Missionary Ridge and through some urban areas, to restrict truck traffic to only one lane. This study showed the effect that decreasing truck traffic would have on I-24. One rail car would handle the freight that now requires four and a half trucks to carry. One barge can contain the contents of 70 trucks. However, it was noted that it is not realistic to expect this to happen.
Improvements for emergency response was another proposal. This could be accomplished by adding an emergency turn lane from the Georgia state line to the ridge cut in Chattanooga or by working with GDOT to improve emergency response time on the Georgia portion of the road.
Concerns were also expressed about the speed limits, with suggestions to either increase or decrease them. It was also noted that all lanes throughout the state are 12 feet wide even though the perception was that some were narrower. Additonally, recommendations were also made for beautification such as landscaping the roadway or consolidating billboards. Rock-slide mitigation was a matter of concern, especially on Monteagle Mountain.
The costs to make some of these improvements were shown as points of reference.
To add one lane in each direction of an Interstate through a flat landscape would cost $7 million per mile. To build it in an urban or mountain area would cost $27 million per mile.
To widen a typical 300-foot-long bridge on an interstate would cost $1 million per mile.
Adding a completely new interstate through a rural area would cost between $8-$36 million per mile, or $18-$86 million in an urban area.
Installation of a new traffic signal costs from $90,000-$120,000.
The addition of an express bus line would cost anywhere from $100,000-$300,000 and a Rapid Transit Train would be $3-$10 million per mile. A commuter rail line would cost from $5-$15 million for each mile and $40-$70 million for a light rail transit line.
Additional comments or ideas about improvements to the I-24 corridor can be conveyed to TDOT by phone or by email. Information can also be accessed by going to the TDOT website to see the entire list of proposed projects. A click on the “public meetings” tab will have dates for the upcoming meetings where citizens are encouraged to participate.