Ryan Dam facts for kids
Quick facts for kids Ryan Dam |
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| Location | Cascade County, Montana, USA |
| Coordinates | 47°34′10″N 111°07′29″W / 47.56944°N 111.12472°W |
| Construction began | 1915 |
| Owner(s) | NorthWestern Corporation |
| Dam and spillways | |
| Impounds | Missouri River |
| Height | 61 ft |
| Length | 1,336 ft |
| Reservoir | |
| Total capacity | 5,000 acre-feet (6,200,000 m3) |
| Power station | |
| Installed capacity | 60 megawatts (80,000 hp) |
| Annual generation | 441,430,000 KWh (2009) |
Ryan Dam is a large hydroelectric dam on the Missouri River in Montana. It is about 10 miles (16 km) downstream from the city of Great Falls. This dam helps create electricity using the power of moving water.
The dam is 1,336 feet (407 m) long and 61 feet (19 m) high. It holds back water to form a reservoir that is 7 miles (11 km) long. This reservoir can store about 5,000 acre-feet (6,200,000 m3) of water. Ryan Dam is known as a "run-of-river" dam. This means it uses the natural flow of the river to make power, rather than storing huge amounts of water.
Ryan Dam was built on the biggest of the five Great Falls of the Missouri. This specific waterfall is sometimes called the "Big Falls." Since 1915, the dam's power station has been a big part of this 87-foot (27 m) high waterfall.
Contents
Ryan Dam: How It Works
Ryan Dam is split into different parts. It was built just upstream of the "Big Falls" and a small piece of land called Ryan Island.
Dam Structure Explained
On the right side of the dam, there is a special concrete structure called a spillway. When it's working, this spillway lets water flow over the remaining parts of the waterfall.
The middle part of the dam has a wall, or dike. This dike stretches from the bottom of the falls to Ryan Island. It helps separate the water that has gone through the power plant from the main river. This water rejoins the river a bit further downstream.
This middle section also has a concrete structure that faces the right side of the river. It holds the outlet works. This is where a strong jet of water bursts out and flows over the waterfall.
The Powerhouse
The left side of the dam is home to a large powerhouse. This is where the electricity is actually made. The powerhouse has six units that use the force of the water to spin turbines and generate power. A concrete structure sits on top of the powerhouse.
History of Ryan Dam
Ryan Dam has been an important part of Montana's power supply for over a century.
Who Owned the Dam?
The dam was first built by a company called Montana Power Company. Later, in 1997, PPL Corporation bought it. Then, in 2014, NorthWestern Corporation became the owner of Ryan Dam.
Changes to the Missouri River
When Ryan Dam was built in the Missouri River gorge, it changed the river quite a bit. It flooded some of the smaller waterfalls between Grand Fall and Crooked Falls, which are upstream. The dam also reduced the amount of water flowing over the Great Falls. Because of this, you can now see much more of the rocky riverbed.
The dam was built right on top of a 10-foot (3.0 m) waterfall that famous explorers Lewis and Clark saw a long time ago.
Other Dams Nearby
Ryan Dam is one of several dams along this part of the Missouri River. Upstream from Ryan Dam, you'll find Cochrane Dam, then Rainbow Dam, and the highest one is Black Eagle Dam. Downstream from Ryan Dam, the next one is Morony Dam.
