The Military-Industrial-Recreational Complexes of the Upper Little Tennessee River

To make aluminum, start with concrete. 

The Upper Little Tennessee River--Crucible of Modernity 

The Military: Among other grizzly superlatives, World War II marked the end of the Iron Age.  For nearly 3,000 years, weapons of iron and iron alloy (like steel) had dominated warfare. Although WWII was largely fought with steel tanks, mortars, and rifles, the most lethal weapons were composed of metals unknown in premodern times: Aluminum and Uranium. 

The Industrial:Despite the prevalence of bauxite (aluminum ore) in the earth's crust, pure aluminum was unknown before the 1850's. Aluminum never occurs as a metal in nature (you won't ever stumble across a nugget of the stuff, nor pan flakes of it from a mountain stream), and it cannot be produced through chemical leaching or smelted over a flame--aluminum can only be purified through the application of copious amounts of electricity. (Although pure uranium can be produced through smelting, the resulting metal is useless for atomic purposes--separating out the useful isotope is a complex, repetitive and highly energy-intensive process).   

In the US, the machines of the 'Jet Age' and the 'Atomic Age'--synonyms for modernity itself--were largely built from metals refined in Eastern Tennessee. Neither aluminum nor uranium ore were mined in the Appalachian Mountains, and the region was certainly no center of industry or science in the early twentieth century--but ore and expertise could be imported. What was in Eastern Tennessee that could not be found elsewhere? The gorge of the Little Tennessee.  

Dangerous Waters

In 1909, the Aluminum Company of America (Alcoa) opened an aluminum smelter (the plant is called a smelter, but it operates through electrolysis) in Maryville, Tennessee. At the time, steam turbines were a new technology; massive coal-burning power plants had yet to be perfected. Hydroelectricity offered the cheapest, most reliable and most copious source of electricity, and a cheap, reliable and copious source of falling water could be found untapped in the gorge of the Little Tennessee River, upstream from the small town of Maryville, Tennessee. At the time, there was no power grid; the longest transmission line in America stretched only fifty miles. The ore would have to be brought to the power, not the other way around.

If you visit Maryville, Tennessee today, you will notice the preponderance of high tension lines.   

They're everywhere--the transmission lines in this picture alone carry enough power for 300,000 homes (Maryville-Aloca is a city of only 10,000 households) 

Follow these transmission lines out of town--they lead to a chain of mountain lakes. 

The Recreational: From its headwaters in the Smoky Mountains, the Little Tennessee River falls over 1,000 feet into the syncline of the Great Valley; it cuts a steep gorge with conveniently-spaced narrows; four dams now create a chain of lakes arranged like perfect stair-steps. Thirty miles of slack water fill the gorge; the headwaters of each reservoir back neatly up to the base of the next dam, and the entirety of the river's energy is captured inside powerhouse turbines. 

Three of these lakes--Chilhowee, Calderwood, and Cheoah (impounded by dams of the same names) are 'run-of-the-river' reservoirs--the narrow lakes follow the contours of the gorge. They are scenic, but limited area and shoreline makes these reservoirs better suited for fishing than water skiing. The massive Fontana Dam, however, creates a far larger lake on the river's headwaters. Its shoreline is almost entirely public land--the northern shore marks the edge of the Great Smoky Mountains National Park and the southern shore is largely National Forest. Hiking, boating, fishing, and wildlife watching opportunities abound. 

Fontana Dam is the tallest dam in the Eastern US (though only the twentieth-tallest in the nation). It is also notable for having been constructed during WWII, providing critical power for the production of aluminum for airplanes and the uranium used in the first atomic bombs.  

One thing Fontana is not, however, is beautiful. The dam's straight edges resemble a jersey barrier. 

Fontana Dam

A jersey barrier. 

The dam is not especially noteworthy from an engineering standpoint--aside from sheer mass, there is little that is unique to its design. It's a crowd-pleaser, though; a visitor's center on the southern rim has an impressive archive of construction memorabilia. 

It also leaks. Slowly, but enough to sustain a few plants growing from cracks in the concrete. 

A preemptive guilt trip 

An old turbine on display at the dam's base. 

Santeetla: The true engineering oddity is not far away, however. A half-mile downstream from Fontana, on the opposite shore from the highway, you will find a powerhouse... without a dam. The building's tall windows conceal its true scale--the water head (the height from which water falls to the turbines) at this site is over 600 feet--if there were a dam here, it would be America's fifth tallest.   

But there is no dam. Just a tank. Surely that can't be the reservoir!

It is not unusual to see a powerhouse removed from its dam--many early hydro plants used a diversion flume to bring water further downstream, increasing the head height. These turbines, however, are not fed by a flume running from Fontana Lake.  In fact, the powerhouse predates the Fontana Dam by twenty years.  

You can drive up to the tank (Rhymer's Ferry is your road for this); if you do, you will find that no open flume, creek or pond fills the tank.

Follow that pipe!

Instead, it's a sealed pipe a dozen feet in diameter. The pipeline runs aboveground for a short distance, then disappears into the mountain; a few miles to the south, the pipeline emerges again near Yellow Creek Road for a couple hundred yards.

Pipeline crossing the Yellow Creek Valley 

It's easy to spot.

Note that this pipeline isn't headed upstream--the route leaves the Little Tennessee Valley entirely and crosses a ridge, moving perpendicular to the river. The next time the pipeline appears, it crosses the Cheoah River.  The river itself has been reduced to a trickle, just enough to dampen the riverbed. Where does all the water go? It's in the pipe, of course. 

The final nine miles of the Cheoah River is diverted through this pipe--1,000 cubic feet of water per second; given the pipe's diameter, that means the current inside is flowing at around 7mph--as fast as a typical Class IV rapid. Where the river crosses itself, the pipeline is actually a siphon, with the suction of water in the 'downstream' portion pulling the current up the opposite bank.      

Imagine a whitewater rapid, charging uphill--that's what's happening inside this siphon!

Crossing the highway for scale. 

End of the line--the pipeline emerges from Santeetla Dam. 

Diverting a river across a divide to a powerhouse located an entirely different watershed is unusual, even unprecedented. (Numerous other diversion dams exist, of course; many channel water across divides--but always for irrigation, not hydropower. Long flumes or sluices are also common in early hydro projects; however, other sluices follow the course of the impounded river and eventually drop the water back into the original watershed.)  

The Santeetla Dam is a prime example of the High Imperial Mayan style of architecture. Note how the spillways resemble pyramids and the concrete is weathered to a streaked brown patina.

The fecundity of the surrounding forest adds to the dam's 'jungle ruins' aspect.    

Which begs the question: why here? A quirk of geography, of course.

Damming the Choah River proved problematic: The best available site was located nine miles upstream from its confluence with the Little Tennessee--building a dam here would mean ceding 500 vertical feet of the river's course (around 200 MW worth of potential power). Unacceptable.

Building a lower dam, however, would be impossible--the gorge is too wide at its base, and the lack of a high wall also precluded a downstream flume (to be effective, the headstock must fall nearly straight down--a sloping flume loses power to friction).  

So this is the ingenious solution Alcoa's engineers engineered--if the dam could not be built at the edge of slack water, the Cheoah must be brought to the slack water. Siphoning the Cheoah across the divide and dropping the water into the Little Tennessee not only enables a 230 foot dam to generate power from a water head 600 feet high, it also allows that water to pass through a second set of generators at Cheoah Dam (on the Little Tennessee upstream of the confluence).     

Visiting: The Military-Industrial-Recreational Complexes of the Upper Little Tennessee are located about twenty miles east of the town of Maryville, Tennessee on Highway 129. Here's a map. All services can be found in Maryville as well as Robbinsville, NC, located between the Fontana and Santeetla Lakes.  

Free campsites are available on the shore of Santeela Lake, and numerous campgrounds are located throughout the surrounding National Forest and GSMNP. Boats can be launched and rented at both lakes, and superlative hiking trails run through both the Great Smoky Mountains and the Joyce Kilmer Forest. 

Summer is the best time to visit, but winter snowfalls are infrequent and short-lived. When driving on Route 129, be aware that this twisting highway, known as the "Dragon's Tail" is popular among motorcyclists and you will encounter riders displaying a broad spectrum of skill and judgement.