Newcomers to the Missouri Ozarks can be excused for assuming Bagnell Dam at Lake of the Ozarks was the first river powered electric generator. Built in 1930-31, Bagnell was one of the first, but not Missouri’s first.

Newcomers to the Missouri Ozarks can be excused for assuming Bagnell Dam at Lake of the Ozarks was the first river powered electric generator. Built in 1930-31, Bagnell was one of the first, but not Missouri’s first.

Back in the late 1920s, Central States Power and Light Corporation began construction of what was then known as the Little Niangua Hydro Project, now called “Tunnel Dam.”

While relatively dwarfed by Bagnell’s 215 megawatts of electric power, Tunnel Dam has contributed access to almost three megawatts of power for going on 90 years.

The name Tunnel Dam comes from a natural tunnel carved by flowing water from the Niangua River proceeding from Bennett Springs, and other flowage into Camden County. The tunnel was enlarged in the early years to create a 40-foot waterfall to drive turbine wheels. Prior to 1920, some three dozen water-powered gristmills took advantage of the Niangua’s waterpower.

The operator, Sho-Me Power Electric Cooperative, has initiated the process for the renewal of the dam’s federal license, last issued in 1994. The examination runs through 2024, when the current license expires and is due for renewal

In August of last year, Sho-Me staff removed and replaced an oil-filled transformer with a new, more efficient dry type. This update improved generating power and ruled out the possibility of an oil spill on the Niangua’s pristine waters.

Inside the powerhouse, a pair of turbines from 1929 continue to operate.

At the recent meeting Thursday at the Tunnel Dam office, two state environmental agencies, the US Fish & Wildlife Service as well as the Osage Nation Historic Preservation Office discussed the future requirements for renewing the Tunnel Dam’s license to operate for another 40 years.

Issues such as sedimentation above the Tunnel Dam, various crayfish populations above and below the powerhouse, potential habitat for the Missouri Eastern Hellbender salamander plus public use of the waterway for recreation were discussed. One state agency called for a study of the oxygen content of the water below the dam, only to find it’s sister agency had an oxygen study underway.

Comments from the public are due in 60 days. Show Me Power will develop its license application for the Federal Energy Regulatory Commission over the next two years. An approved renewal or rejection is expected by 2024.