current rushes powerfully
Narrator
The age-old dream of capturing the raw power of Niagara Falls became a reality in 1896 when the Niagara Power Company built a large hydroelectric plant just upstream. Niagara Power selected the Westinghouse Company to manufacture the electrical generating system, recently invented by visionary scientist Nikola Tesla. The large plant drew nationwide attention when it sent electricity 11 miles to Buffalo, New York, where it easily powered the city's streetcar system.
streetcar bell dinging
Narrator
The success at Niagara Falls triggered a kind of hydro-mania, which swept into Wisconsin. Catching the fever was Madison entrepreneur Magnus Swenson, who persuaded investors to fund his vision of electrifying Wisconsin by building large hydroelectric plants. At Kilbourn-- now known as Wisconsin Dells-- Swenson purchased a site and began building a dam and a hydroelectric plant. And even before he finished that project, Swenson began searching for a bigger site with more drop that would produce more power. Just north of Prairie du Sac,
he found what he was looking for
a site so large that it would be second only to Niagara Falls in size. But there was a problem. It's a location that is not a typical location to build a hydro because it's a very sandy river bottom. In that part of the river, the sands extend somewhat beyond 50 feet thick. And so, if you think of building a dam, you need to typically anchor it or key it into some kind of solid foundation. In this case, there's nothing there. It's just sand.
Narrator
Swenson worked with Daniel Mead, a professor of engineering from the University of Wisconsin, to come up with a solution for the site.
Amanda Blank
And they designed a very unique one-of-a-kind facility that had never been built before.
Carson Mettel
Mead would be given the credit for coming up with this idea of building the dam on, essentially, a forest of piles.
Amanda Blank
Basically, a wooden pile, it's a tree.
laughs
Amanda Blank
So what they did is they had to do logging, and they would find a variety of different types of species, and they actually drove them into the ground using steam-driven pile hammers.
steam-pile hammer has a slow driving vibration
Amanda Blank
So, this idea of building a pile foundation required nearly 12,000 trees, and they had to be of the right material and the right diameter, and they had to be nice and straight. Maybe the top two feet of that pile is there, and then they will pour a concrete cap on top so that whatever weight they put on top of that-- whether it's a wall or part of the dam-- it's then being supported by all those pilings.
Narrator
Starting at the Prairie du Sac stockyards, crews also used pile drivers to build a rail line north to the construction site. Contractors then brought in boilers, to build a steam-driven electrical plant. At a time before earthmovers or dump trucks, the plant's generator powered a remote-controlled electric rail system.
rail cars move quietly
Narrator
Tracks extended several miles to a stone quarry and gravel pit. And while rail cars hauled the raw materials back to a concrete mixing site, much of the excavating work was done with shovels. One of the quotes I've heard is that the dam was built with steam power, horsepower, and manpower. And it took about 400 people to build the dam, and they really seemed to be separated into two different groups. There were the local laborers, and they had an area on the west side of the river. And there they had sleeping quarters, and they had a nice dining hall. And then, immigrant workers were recruited from the Chicago area. They came from Poland and Serbia, Russia, Italy, and, as it's described, they had more of a tent camp over there. I do believe they were able to come over for food, but really the two, as I understand it, didn't mix that well. And I think there was probably some animosity there, but they all did work together, and it took all 400 of them to get the job done.
drivers pounding steel "bang"
Narrator
To prepare for building the powerhouse, pile drivers began pounding down sections of a steel wall, or cofferdam, around the worksite, that would then be pumped dry. But in the fall of 1911, the river rose quickly and soon breached the walls and flooded the site. They had a record-breaking flood, six inches higher than had ever been recorded before, and it washed out a lot of the progress they had made. They had another one in 1912, which did the same thing and wiped out a lot of the progress.
Amanda Blank
One bad winter where there was-- they call them ice dams, so, large sheets of ice-- that damaged a lot of the construction, and they had to rebuild portions of the dams. And they continue to press on.
Narrator
Contractors hired divers to inspect the damaged areas of the cofferdam walls.
bubbles emerge from deep water
Narrator
And after replacing damaged sections, and pumping water from the site, workers began shoveling out an area where the powerhouse would take shape.
shoveling
Narrator
Train cars brought in tons of concrete and steel. Steel forms gave shape to the draft tubes, where water would exit the powerhouse. Workers poured great quantities of concrete using hand carts.
Amanda Blank
They had masons on-site to do the masonry. The powerhouse itself is very large by today's standards. It's an over three-story high building, and the brickwork is just-- it's beautiful.
Narrator
And as the powerhouse rose up, attention turned toward finishing the floodgates that would regulate the flow of the river.
light piano music
Narrator
And once the water turbines were installed and connected to the generators, the plant was finally ready to begin producing electricity.
Amanda Blank
I like to tell people it's like working in a living museum because our equipment's original. We've upgraded electronics and controls and safety devices, but mechanically, everything here is running the same.
Carson Metter
So, since it was completed in 1915, we've been doing additional analyses and refurbishment and looking at it in a lot of different ways. And today we have a lot more sophisticated tools and can do very sophisticated computer models. But what we find is that the design is very, very... eloquent, is the way I put it. It's very perfectly balanced. Even today, when you look at the loads and the forces on it-- it's wonderfully balanced. It's actually hollow, which is interesting. You can walk right through the middle of the dam. But it's stood the test of time. It's lasted a hundred years.
Amanda Blank
To be able to see it every day and to see it's still thriving and offering electricity to the community and being a big part of the community, it's-- it's impressive.
current rushing, birds calling
lure splashes, thuds into water
light orchestral music
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