Benefitting from additional flood modeling, the Federal Energy Regulatory Commission staff dropped objections to a flood pool elevation change and issued a final environmental impact statement recommending the relicensing of the 182.5-MW Martin Dam hydroelectric project on Alabama's Tallapoosa River.
FERC staff had issued a draft EIS in 2013 that recommending relicensing Martin Dam (No. 349) but objecting to licensee Alabama Power Co.'s proposal to retain higher reservoir levels in winter.
Alabama Power Co., a unit of the Southern Co., filed an application to relicense Martin Dam in 2011. FERC staff issued the draft EIS in 2013, recommending the commission relicense the project as proposed by Alabama Power with a number of FERC staff modifications.
The utility proposed to continue to operate Martin Dam in peaking mode but to modify operations in several ways. To provide higher reservoir levels in winter for recreation and to help ensure Lake Martin reaches its summer pool level by the end of May each year, Alabama Power proposed to raise the winter flood pool by 3 feet and raise the operating curve and drought curve proportionately. The draft EIS rejected that proposal because modeling indicated the reduction in flood storage would result in an increase in flood elevation downstream of the projects.
That assessment changed in the final EIS.
"While Alabama Power's initial, worst-case modeling suggested the possibility of increased flooding and potential damage to structures and roads, the company's subsequent, more refined analysis indicated little potential for a 3-foot increase in the winter flood pool elevation to increase peak water elevations downstream," the final EIS said.
Among the licensee's proposed environmental measures, FERC staff also rejected a proposal to study the distribution and abundance of American eels in the Tallapoosa River from the project tailrace to the mouth of the river. Instead, staff proposed that Alabama Power trap eels annually at Martin Dam to determine if eel passage might be necessary. The EIS also rejects a proposal to remove 373.1 acres from the project boundary under the Shoreline Management Plan because the land still serves project purposes.
If the project were relicensed with no changes, project power would cost about $120.10 per MWh less than the cost of alternative power. Under Alabama Power's proposal, power would cost $119.45/MWh less than alternative power. Under the FERC staff-endorsed alternative, power would cost $119.44/MWh less than alternative power.
The EIS may be obtained from the FERC Internet site, www.ferc.gov, under http://elibrary.ferc.gov/idmws/common/OpenNat.asp?fileID=13826525.