Upper North Fork Feather River Project facts for kids
The Upper North Fork Feather River Project is a big system of dams and power plants in the Sierra Nevada mountains of California. It uses water from the North Fork Feather River to make electricity and also helps deliver water for farming. This project has three main dams, five power plants, and many tunnels in Lassen and Plumas Counties. It can make a lot of electricity, about 362.3 megawatts (MW), and provides water for farms from spring to fall. The project is owned and run by Pacific Gas and Electric Company (PG&E).
This project is one of many on the North Fork Feather River. Together, they form a huge system for making power, often called the "Stairway of Power."
Contents
How the Project Started
Early Ideas for Power
The idea for this project came about in the early 1900s. A company called Great Western Power Company wanted to build it. Their goal was to create hydroelectricity and store water for farms in the Sacramento Valley.
In 1908, the first power plant, called Big Bend or Las Plumas, was finished. It was located southeast of Paradise. This plant could make 40 MW of electricity, which was sent far away to Oakland, about 154 miles (248 km) away. This power station replaced an older one from 1880. In 1910, the Big Bend Dam was built. It was the first permanent dam on the Feather River and helped the power plant work better.
Building these early parts of the project was hard. There were not many roads in the mountains. So, building supplies were brought in by the Western Pacific Railroad, which was also being built at that time. When it was finished, the Big Bend power plant had some of the biggest parts of any hydroelectric plant in the world. However, the river's water levels changed a lot with the seasons. This made it hard to make electricity all year round.
Building Lake Almanor
To solve the problem of changing water levels, a large storage lake was needed. An engineer named Julius M. Howells suggested building it at a place called Big Meadows. Great Western Power Company started buying land there. But the local people were not happy about it. The small town of Prattville in Big Meadows was burned down on July 4, 1909. People thought it was arson, but it was never proven.
Construction of the Canyon Dam began in 1910 to create Lake Almanor at Big Meadows. A rough road was built to bring workers and materials to the site. A company town called Canyondam was set up there. The dam's original design was changed because of safety worries. In 1913, the partly built dam was blown up, and a new earth-filled dam was constructed. The lake was named Lake Almanor by combining the names of the daughters of Guy C. Earl, a company vice president.
This new lake, which could hold a lot of water, made sure there was a steady supply for the power plants and for farming in the summer. A part of Great Western Power Company, called Western Canal Company, managed the water for farmers near Oroville.
Expanding the System
Between 1919 and 1921, the first Caribou Powerhouse was built on Butt Creek. A tunnel was dug from Lake Almanor to the creek to send water to the powerhouse. A high dam on Butt Creek was built in 1924 to store more water and make more power. Between 1925 and 1927, Canyon Dam was made even bigger, increasing Lake Almanor's capacity.
In 1930, Pacific Gas and Electric Company (PG&E) bought the Great Western Power Company and the Upper North Fork Project. The Western Canal Company still kept the rights to the water from Lake Almanor and other PG&E lakes. This made sure that water for farming continued to be delivered.
The third dam for the project, Belden Forebay, was built in 1958. It was placed on the North Fork to help the Caribou power plant. The Caribou No. 2 power plant was also built in 1958 to make more electricity. In 1962, Canyon Dam was raised again, making Lake Almanor its current size.
In 1968, the huge Oroville Dam was finished on the Feather River. It created Lake Oroville, which covered most of the lower North Fork, including the Big Bend Powerhouse and Dam. PG&E then built the Belden Powerhouse in 1969 to replace the power that was lost.
The last part of the project, Oak Flat Powerhouse, was built in 1985. It makes electricity from water that is released into the river to help fish. This is important because federal law says a certain amount of water must flow in the river sections between the dams.
How the Project Works Today
Lake Almanor and Butt Valley Powerhouse
Lake Almanor is the main storage lake for the project. It is formed by the 130-foot (40 m) high Canyon Dam. Lake Almanor is one of California's largest artificial lakes by surface area. The dam and lake control water from a large area, including parts of Lassen Volcanic National Park.
Water from Lake Almanor is sent through the Prattville Tunnel to the Butt Valley Powerhouse. This powerhouse was finished in 1958. It is located on Butt Creek, just above Butt Valley Reservoir. The Butt Valley Powerhouse can make 41 MW of electricity and produces about 156.1 GWh each year.
Butt Valley Dam and Caribou Powerhouses
The dam on Butt Creek was finished in 1924. It creates Butt Valley Reservoir, which holds water for the Butt Valley Powerhouse. Water from Butt Creek and from the Butt Valley Powerhouse then flows through tunnels from Butt Valley Reservoir to two powerhouses near Caribou.
The Caribou No. 1 powerhouse, finished in 1921, can make 75 MW of electricity. It produces about 171.4 GWh each year. The Caribou No. 2 powerhouse, finished in 1958, is larger. It can make 120 MW of electricity and produces about 442.2 GWh per year.
Because Caribou No. 2 has newer and more efficient machines, it runs all year. Caribou No. 1 is mostly used when more electricity is needed or when Caribou No. 2 needs maintenance.
Belden Dam and Belden Powerhouse
Belden Dam is a smaller dam on the North Fork Feather River. It was finished in 1958. This dam and its reservoir act as a holding area for the water coming from the Caribou 1 and 2 powerhouses. It works like a "run-of-the-river" system, meaning that the water flowing in must flow out at about the same rate.
The Oak Flat Powerhouse is located at Belden Dam. It makes electricity from water that is released into the North Fork. This water is important for fish and wildlife, as the river would otherwise be dry because of the water being sent to the Belden Powerhouse. This 1.3 MW plant was built in 1985 and produces about 6.7 GWh per year.
Most of the water, however, is sent through a 5-mile (8 km) long tunnel to the Belden Powerhouse. This powerhouse is located on Rock Creek Reservoir. The 125 MW Belden Powerhouse, finished in 1969, produces about 395.5 GWh per year.
