The 24-MW LaGrande hydroelectric project has been a reliable source of power generation for owner Tacoma Power for the past century. This facility, on the Nisqually River in Washington State, is the most recent inductee into Hydro Review‘s Hydro Hall of Fame.
By Patrick McCarty
The city of Tacoma, Department of Public Utilities, Light Division (dba Tacoma Power) has deep roots in the hydropower industry that were planted with the construction of the 24-MW LaGrande Powerhouse on the Nisqually River in Washington State.
At the turn of the 20th century, the city of Tacoma’s electrical system distributed power that was purchased from competing companies. Tacoma’s city council was looking for alternatives to free the city from the grip of private power interests. It faced a decision to either initiate a new contract with a private power provider or build its own plant. In 1909, the city took a bold first step as it looked to the Nisqually River for the location to construct the area’s first hydroelectric facility.
To acquire the necessary funding for the project, the city of Tacoma sent a $2.3 million bond measure to a vote of the people. This was the amount required to construct the plant.
However, Stone and Webster, the city’s only power provider, was threatened by the potential development of a municipal-owned power generation facility. Before the citizens could vote on the measure, the Boston-based company raised rates and shut off power to the pumps that supplied water to the city. This attempt to thwart the new development backfired when Tacoma voters passed the bond measure to fund the LaGrande Powerhouse with a 75% approval rate.
The Tacoma Times called the election a victory that freed the city of Tacoma from the grip of special interests and proclaimed the city, with its own electrical supply, could now begin building toward commercial greatness. Since the facility was completed in 1912, it has produced power almost continuously and helped the city achieve that goal. In 1913, the city’s demand for electricity was 20.4 kWh, and the LaGrande Powerhouse supplied that entire amount. Now, the project is Tacoma Power’s second largest generating facility, producing power that is augmented by other generating resources on three other western Washington rivers.
Building the LaGrande Powerhouse
Development of the LaGrande Powerhouse required the company (then called Tacoma City Light) to jump over many of the same hurdles an organization wanting to build a new hydro facility would face today.
The location chosen for the powerhouse – on the Nisqually River, 36 miles southeast of Tacoma at the foot of Mount Rainier – presented challenges. To gain rights to use the property for building the plant, the city had to file a lawsuit against several private landowners and face a jury. The jury awarded $95,000 to the landowners. When the landowners appealed, the case was tried and dismissed in the Washington State Supreme Court, putting the final piece in place to begin the project. With bond money secured and the land acquired, the utility hired surveyors, drafters and engineers to design the hydro project.
Construction of the hydro project began in February 1910 and included construction of a 225-foot-long diversion dam rising 35 feet above the river, which directed water into a settling channel (to remove silt), then into a 2-mile tunnel blasted out of solid rock. The tunnel fed into the forebay and led to four penstocks that dropped 410 feet to a powerhouse equipped with four Allis-Chalmers 6-MW turbines and generators. A 36-mile-long, 69 kV transmission line carried the electricity into Tacoma.
The project began operating in November 1912 on time, on budget, and according to plan.
|The LaGrande powerhouse, shown here in 1912, was the first publicly-owned power generation unit in the city of Tacoma, with a capacity of 24 MW at that time.|
All eyes on LaGrande
The LaGrande project changed the way folks in Tacoma thought about electricity.
Before the powerhouse was operational, The Tacoma Times wrote a story that started with these words:
That little kilowatt.
After the city council had inspected the new Nisqually power plant yesterday and had the various details of the institution explained by the engineers on the ground, the general verdict was that the kilowatt, seemingly unimportant and entirely intangible, is destined to play a mighty important part in the future of Tacoma.
For the kilowatt is the name given to that little unit of electric energy bought by the people for 6 cents to light up the house.
Ray Freeland, a utility commissioner, envisioned Tacoma as an “electric city,” where every home had an electric stove and other electric gadgets. The LaGrande Powerhouse provided the opportunity to make the vision a reality by providing power to meet the city’s demand.
“Apparently the thing for the city to do is to quit discussing how much or how little the plant will turn out and get in and sell the Juice. Citizens are getting positively hilarious over Commissioner Freeland’s proposition to make Tacoma the electric city of the world by getting everybody to cook with electric juice,” said a Nov. 12, 1912, story in The Tacoma Times.
As Freeland desired, the city of Tacoma rapidly increased its use of electricity, due in large part to the readily available power generated in the LaGrande powerhouse.
But questions arose about the plant’s ability to supply the city’s needs very quickly after the plant became operational. By 1918, the city boasted 418 street lights, and 600 electric ranges were in use. The city was about to exhaust the capacity of the Nisqually plant, and new sources of power were urgently needed.
The end of World War II created a further increase in demand for electricity, and the public power utility did not know if it could meet it. It had to decide how to meet its growing demand. The utility formed a special commission that was tasked with wrestling over a decision: Would the utility develop its own hydroelectric fleet or purchase power from the Bonneville Power Administration?
“Tacoma can’t afford to wait much longer to make one of the most important decisions in its 51-year history,” reported The Tacoma Times in August 1944.
Although Tacoma City Light built the two-powerhouse Cushman Hydroelectric Project in the 1920s (43-MW Cushman No. 1 and 81-MW Cushman No. 2), it looked to the LaGrande Powerhouse and Nisqually River to provide even more power to meet post-war demand.
In the 1940s, the utility replaced the original diversion dam through construction of Alder Dam and its 50-MW powerhouse and LaGrande Dam. Alder Dam sits just downstream from the original diversion dam, and LaGrande Dam is 1.5 miles downstream from that location. Another 1.7 miles downstream is the LaGrande Powerhouse, which Tacoma City Light upgraded at the same time by adding a 40-MW turbine-generator unit.
These changes and upgrades in-creased the capacity of Tacoma City Light’s hydroelectric fleet from 24 MW to 212 MW, successfully meeting the city’s growing need.
|This window sticker, circa 1945, shows Alder Dam and the reservoir just upstream.|
Overcoming nature’s challenges
Tacoma City Light faced significant challenges when building the Alder and LaGrande dams. Faults in the rock were found at both dam sites, which called for more excavation than was initially expected. Additionally, the war decreased the available workforce, making it a challenge for Tacoma Power to find capable workers.
Because of all the challenges, costs increased on the project. The worst unexpected expense occurred when the 6,500-foot-long tunnel running from LaGrande Dam to the powerhouse sprung a leak and caused a slide. The leak and its subsequent repair delayed the project for five months.
Editorializing on the project, the Tacoma News Tribune said, “About the only positive thing about the whole affair is that Tacoma did need the additional power, for it has had to purchase about $1 million annually from the Bonneville and Seattle systems in the past few years.”
The project costs increased from the budgeted amount of $11 million to an actual $23.6 million, which made “frugal minded Tacomans shudder,” said the Tacoma News Tribune.
|The original LaGrande powerhouse still stands 100 years after it went online and currently provides a capacity of 64 MW.|
The project over the years
In 1989, Tacoma City Light entered into a settlement agreement with the Nisqually Indian Tribe that was the starting point to develop and maintain a long-term cooperative relationship. The agreement provided for a new minimum flow regime designed to enhance fisheries in the Nisqually River. The settlement paved the way for a new 40-year Federal Energy Regulatory Commission operating license for the project that was issued in 1997.
Tacoma City Light automated the Nisqually project in 1991 through the installation of two central plant control systems.
The facility survived a natural disaster in 1995. When the Nisqually River reached flood levels higher than any in recorded history, the LaGrande Powerhouse flooded. After a significant amount of work, generator rewinds and a bit of ingenuity, Tacoma City Light employees got the project up and running again the following year.
In 2003, the utility (now called Tacoma Power) began the process of upgrading and installing new automation systems, as the equipment was obsolete. And in September 2008, Tacoma Power received low-impact hydropower certification for the Nisqually River Hydroelectric Project (including the 64-MW LaGrande powerhouse) from the Low Impact Hydropower Institute.
A valuable decision
From its conception, the LaGrande Powerhouse proved to be a valuable investment for the city of Tacoma. In June 1915, The Tacoma Times reported that the project had already earned more than $1.25 million.
The decision to offer public power and build the LaGrande Powerhouse, however, could be considered one of the biggest in Tacoma’s history. It set a standard and a legacy that has lasted 100 years and will very likely last 100 more.
Pat McCarty, generation manager for Tacoma Power, is responsible for the utility’s seven hydroelectric plants and the associated fish, wildlife, and recreational activities.