The U.S. Army Corps of Engineers, Nashville District is receiving public comments through August 8 on the Tennessee Department of Transportation’s application for permits in regard to the construction of a new Sligo bridge and the demolition of the old one.
Scott Fanning of the Regulatory Branch of the Corps of Engineers Nashville District explained the reason for the public comment period in the following audio clip:
Federal and or state approval is required in order for the proposed construction work to be done including water quality certification from the State of Tennessee in accordance with the Clean Water Act . The Corps of Engineers Real Estate Division must also approve an easement on government lands and waters which is this case totals 7.9 acres and a temporary work area license containing approximately 2.45 acres.
Funds for the replacement of Sligo bridge are included in this year’s state budget and bid letting is expected this fall. The existing bridge will remain open while the new bridge is under construction. The new bridge, which will be located about sixty feet to the north of the existing bridge, is to be comprised of two- 12 foot wide travel lanes with 10 foot wide shoulders.
After construction of the new bridge, TDOT proposes to demolish the existing Sligo bridge, which is a seven-span structure consisting of five high steel truss spans and two concrete approach spans with concrete substructures. The total length is 1,374 feet and the width is 27.2 feet. Removal of the existing structure would take both abutments, Pier 1, and Pier 6 one foot below natural ground elevation. Piers 2 through 5 would be removed to an elevation no higher than 600 feet above mean sea level (MSL). Ordinary high water elevation for Center Hill Lake is 648 feet above mean sea level and the normal minimum pool elevation is 618 feet above mean sea level. The existing concrete deck would be removed from the site. Other debris from the demolition which rests below elevation 600 would be left in the lake. This would include steel trusses, concrete and reinforcing steel from the demolition of the piers. Fanning said this proposal might be of some concern to the Corps.
The proposed bridge replacement impacts the lease area for Sligo Marina as well as other outgrants. Access to Sligo Marina will be available during construction however, there will be intermittent closures during the winter. The temporary work/staging area is currently leased to DeKalb County. This area is used as a launching ramp with related parking and the county has no objection of use of this tract during construction. Two locations will serve as encapsulation sites for pyrite. One is approximately 19.6 acres that TDOT acquired on the east side of the river and drains into Blue Springs Creek and the other is approximately 5.7 acres located on the west side of the river at the DeKalb County Landfill and drains toward Falls Creek.
The decision whether to issue a permit will be based on an evaluation of the probable impacts of the activity on the public interest. A permit will be granted unless the District Engineer determines it to be contrary to the public interest.
Any person may request, in writing, within the comment period, that a public hearing be held to consider this application. Requests for hearings shall state, with particularity, the reasons for holding a hearing.
Written statements received on or before August 8 will become a part of the record and will be considered in the determination. Any response to the notice should be directed to the Regulatory Branch, Attention Scott Fanning at Nashville District Corps of Engineers, 3701 Bell Road, Nashville 37214. Phone 615-369-7521 or email scott.fanning@usace.army.mil.