photo by Lawson Whitaker
Construction to widen U.S. 27 that was started in early 2015 will not be complete until early 2019, the Advisory Council on Traffic Safety was told, at its quarterly meeting Wednesday afternoon.
Jim Floyd, assistant vice president of Volkert Engineering, the firm in charge of quality control for the project, said the original cost estimate was $85 million, but was bid at $126 million.
The work will improve 2.3 miles from I-24 to the Olgiati Bridge and include 33 retaining walls and 10 bridges that will be rebuilt. This is the largest project in Tennessee history ever undertaken by TDOT
The work recently completed from the Olgiati Bridge to Signal Mountain Road was done for a cost of $105.6 million. That encompassed a little less than one and a half miles.
Throughout the work two lanes will be kept open in each direction, said Mr. Floyd, so there will be a lot of nighttime work. The end result of this road project is to have six travel lanes, three in each direction. There will be one-two lanes for ramp ingress and egress. The “S” curve just south of AT&T Field will be removed and the road straightened out. New exit and entrance ramps will be built and a “collector road” will be built southbound from 4th to 9th streets. Retaining walls will hold up Cameron Hill along the way.
Construction will be done in four phases, with Phase 1 in progress now. Traffic shifts will take place as the phases change. The focus of Phase 1 is on northbound bridges and a retaining wall at Cameron Hill. The additional lanes will be built to the outside of the existing road. A new exit ramp will be built at Main Street.
For Phase 2, starting in 2016, traffic will be shifted to the new northbound side of the road and median work will begin. Work on the retaining wall will continue as widening the Olgiati Bridge is started. When the last work was done on the bridge, the piers and base was designed with expansion in mind, so no substructure changes will be required. Two lanes will be added across the bridge, one in each direction.
In 2017 another traffic shift will take place for work that will be done on the southbound bridges during Phase 3. Construction on the massive retaining wall and widening the Olgiati Bridge will continue.
Phase 4 will be done during 2018 and completed in early 2019. In this phase, the northbound MLK and 4th Street ramps will be finished. Paving, striping, lighting and ITS will be completed.
The major issues about the new road work involves safety design criteria, traffic capacity, entrance and exit ramps for acceleration and deceleration as well as pavement repairs. The improvements will update the road from the existing highway that was originally constructed in the 1950’s and 60’s when it was designed for a speed of 55 mph. The capacity, at that time, was to handle 15,000-20,000 vehicles per day. Today, there is an average daily traffic volume of 69,806 vehicles daily which far exceeds the original capacity. Studies have shown that 25,000 vehicles exit at 4th Street and another 21,000 are lost at the MLK exit. The new design was created by planning for the need in 20 years.
Answering questions from the audience, Mr. Floyd said that in construction alone, probably thousands of jobs will be created by the work. He said that there are about 30 subcontractors involved in the actual building phases and that most workers will come from Tennessee and probably over 50 percent of them will come from Hamilton County or nearby.
He said that during the work, TDOT will make concessions and there will probably be no large diversions, restrictions or weight limits except for perhaps wide loads.
Concerning safety in work zones, he said during rush hour when traffic slows down, people are the safest. It is during off hours that most accidents in construction areas occur.
photo by Lawson Whitaker