This Tennessee dam helped build the atomic bomb – and nobody knew it

TVA’s Wartime Rush to Build Ocoee Dam No. 3

The Ocoee River in Tennessee hides a secret war story most folks don’t know.

When World War II broke out, America needed power fast for aluminum plants and the top-secret Oak Ridge atomic work. So on July 16, 1941, TVA rushed to build Ocoee Dam No. 3. Workers put up the 110-foot dam in just over a year, though power didn’t flow until April 1943.

Yet this wasn’t the first marvel here. Back in 1912, engineers had built an even more bold thing – a five-mile wooden flume that hugged the mountain, using 8 million feet of pine to make a water highway that gave a small dam big power.

These twin dams tell the story of American know-how you can still see today along Route 64.

Engineers Spotted a Power Opportunity in Tennessee’s Mountains

Back in 1912, East Tennessee Power Company noticed the Ocoee River dropped 270 feet over 5 miles – perfect for making electricity. Building a regular 250-foot dam would cost too much in the rough mountain terrain.

The company’s engineers came up with a smart plan using a wooden water channel to capture the height difference.

They needed power for the new Alcoa aluminum plant going up in Blount County, where workers would turn raw materials into metal parts.

Workers Blasted a Shelf Right Into the Mountainside

Construction teams started blowing up the mountain in 1912 to make room for the huge wooden water channel. They used 289,000 pounds of explosives to carve a path along the steep slopes.

This shelf needed to stay almost flat, dropping just 19 feet over its 5-mile length. The gentle slope would let water travel the distance before dropping 250 feet through pipes at the powerhouse.

The Massive Wooden Water Highway Took Shape

Work crews used 8 million feet of longleaf pine to build the giant wooden channel during 1912-1913. The finished flume measured 14 feet wide and 11 feet deep, running 5 miles along the mountain.

Workers coated the inside with waterproof materials to stop leaks and keep the wood from rotting. The 30-foot tall Ocoee Dam No. 2 pushed river water into the flume entrance. The wooden structure looked like a giant wooden aqueduct clinging to the mountainside.

A Small Dam Packed a Big Punch

The system started making electricity in 1913, with water dropping 250 feet through steel pipes to spin the turbines. The modest 30-foot dam worked like a much bigger 250-foot dam thanks to the flume design.

Electricity flowed to the Alcoa aluminum plant, helping American industry grow in the early 1900s.

Hitler’s War Machine Created an Aluminum Crisis

Nazi Germany took over Poland in 1939 and quickly grabbed much of Europe, forcing America to start building weapons fast.

Making military aircraft needed tons of aluminum, putting huge pressure on ALCOA’s Tennessee factories. The Tennessee Valley suddenly needed much more electricity to meet defense production goals.

TVA began looking for places to build new dams quickly on the Ocoee River.

Oak Ridge’s Secret Power Hunger Changed Everything

The Manhattan Project built uranium plants at nearby Oak Ridge that needed huge amounts of electricity. Oak Ridge’s gaseous diffusion plant became one of the biggest electricity users in the world.

TVA had to supply steady power for both public aluminum factories and the top-secret atomic work. The Ocoee River’s unused water power became vital to keeping the war effort running.

TVA Launched Dam Construction at Lightning Speed

TVA approved Ocoee Dam No. 3 on July 16, 1941, months before Pearl Harbor.

Construction crews broke ground the very next day. The project got top priority status with unlimited government money and materials.

Engineers planned a 110-foot concrete dam with a 2. 5-mile tunnel through the mountain to carry water to the powerhouse.

They squeezed years of planning into days.

The Race Against Time Pushed Construction Crews to the Limit

Teams finished the 110-foot concrete dam by August 15, 1942, just 13 months after starting. The tough 2. 5-mile mountain tunnel was done by November 1942. Workers put in around-the-clock shifts with first pick of scarce building materials.

This rushed schedule stands as one of TVA’s fastest major dam projects ever finished.

The Finished Dam Sat Empty While War Production Waited

Even with the dam and tunnel done, the vital generating equipment got stuck in manufacturing delays. Factories made turbines and generators for other war facilities first.

The dam sat unused through winter 1942-1943 while aluminum plants and Oak Ridge begged for more power.

TVA pushed hard on manufacturers to deliver the equipment as aircraft factories stepped up production for planned Allied attacks in Europe.

Power Finally Flowed to War Industries

The generating equipment arrived and workers installed it by April 1943. The dam started making electricity on April 30, 1943, almost two years after construction began.

Power went straight to ALCOA’s Tennessee factories and helped feed Oak Ridge’s massive electrical appetite.

The dam added crucial capacity during the peak production of B-17 and B-24 bombers that would soon pound German targets.

Two Dams Powered America’s Victory

The 1913 wooden flume and 1943 concrete dam show two different eras of American engineering on the same river. Ocoee No. 2’s wooden flume kept working into the 1970s before getting replaced. Both dams helped make aluminum for more than 300,000 military aircraft during the war.

The electricity they generated also helped produce the materials for atomic bombs that forced Japan’s surrender in 1945, ending the global conflict.

Visiting Ocoee Dam, Tennessee

You can see all three Ocoee Dams along U. S. Route 64 in Cherokee National Forest, though the structures aren’t open for tours. The Ocoee Whitewater Center at 4400 US-64 in Copperhill is open 9 a. m. -5 p. m. daily from mid-March to mid-November with $3 parking.

Water releases change by season – the Middle Ocoee runs weekends in spring and fall, five days weekly Memorial Day to Labor Day, while the Upper Ocoee runs weekends only May through Labor Day.

This article was created with AI assistance and human editing.

Read more from this brand:

• The Civil War choke point in Tennessee that both sides desperately wanted
• Explore the 400-acre enigma of America’s prehistoric South
• The Confederacy’s biggest wimps: two generals left 13,000 soldiers to face the Union at Fort Donelson