Mar 27 , 2012
An inside look at how Avista gathers information about snowpack
Avista owns and operates eight hydroelectric
dams on the Clark Fork and Spokane rivers.
These facilities, together with long term hydro
contracts, make up about half of the total
electric resources available to serve our
Skiers may prefer light and fluffy snow, but heavy and wet snow contributes more to our water supply in the Northwest. Avista counts on water to generate hydropower for our customers. Every year, Avista evaluates snowpack information in the mountains to get an idea of what spring runoff may be like at our dams on the Spokane and Clark Fork rivers. Only a select few get to see this evaluation process up close, so we took a video camera up the mountain to get you a special look at snowpack measurement.
Avista rents snowmobiles so employees can get as close to the snowpack measurement site as possible. Snow depth is measured by pushing an aluminum tube down through the snowpack and all the way down to ground surface. Both the depth and weight of the snow is recorded. An average of all samples taken is calculated and used to represent the snowpack measurement site.
Avista measures 10 sites at Roland Summit in the Lolo National Forest, which is located near the Hiawatha Trail. Once the data is collected, the Hydro Engineering team submits the data to the National Resources Conservation Service who is largely responsible for providing Avista and many other interested parties with reliable water supply forecasts.
The more gradual the snowmelt, the more Avista can maximize that water running through its dams. However, you never know what Mother-Nature is going to do. Regardless, our customers can count on Avista to make the most out of this precious resource in an efficient, reliable and environmentally-responsible way.
If you have questions about lake and river levels, please visit our website
Feb 06 , 2012
By Brandi Smith
Avista recently sent out the latest issue of the Spokane River Newsletter, a quarterly publication that keeps subscribers informed about our activities in and around the Spokane River. Below is an article from the newsletter that describes how we operate the Post Falls Dam during the winter season. Check out the latest issue
and learn more about what Avista has been up to.
Winter river flows and Coeur d’Alene Lake levels
People commonly think floods occur in the spring. But did you know many of the highest levels recorded for Coeur d’Alene Lake have occurred in the winter? For example, on Christmas day in 1933 the lake reached an all-time peak of roughly eleven feet over its summer level.
Coeur d’Alene Lake is a natural lake with an outlet that naturally restricts its outflow. The primary sources of water into the lake are the St. Joe, St. Maries and Coeur d’Alene rivers. The water then flows through the outlet to create the Spokane River. Avista’s Post Falls Hydroelectric Dam is on the Spokane River, nine miles downstream of the lake’s outlet. The dam affects Coeur d’Alene Lake elevation for about half of the year. During winter and spring, lake levels are controlled entirely by the natural outlet restriction and inflows.
The winter months are generally the wet season in our region. Fluctuating temperatures, rain that occurs on top of snow, or extended heavy rain can increase flows rapidly, which in turn can result in quickly-rising river and lake elevations.
Avista’s goal each year is to draw Coeur d’Alene Lake down six to seven feet below the summer level by early January. This allows Post Falls Dam to generate electricity while providing capacity in the lake for later precipitation and runoff. Natural inflows usually exceed our turbine capacity early in the year, letting Coeur d’Alene Lake and the Spokane River find their naturally occurring levels with no influence by the dam. This free flow condition typically continues through spring run-off until late May, June or early July.
River and lake levels can change quickly. We want you to stay safe, so always use caution on the water and comply with all posted notices and closures, especially in the vicinity.
Avista has a 24-hour telephone information line that provides notification of anticipated elevation changes on Coeur d’Alene Lake, Lake Spokane and the Spokane River.
In Idaho, call (208) 769-1357, in Washington call (509) 495-8043
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Nov 07 , 2011
Avista employees rescue stranded shopping cart, remove rusted blight from Spokane River
When Avista’s Ben McArthur saw an unsightly blight in the middle of the Spokane River, near the Hamilton Street Bridge, he didn’t ignore it like the thousands of others who passed by it every day. He and his co-workers took action. A red grocery store shopping cart had found its way onto a small island in the middle of the river. No one is sure exactly how it got there. Low water levels made it stand out.
McArthur and friends would have none of it. McArthur contacted fellow employee Celene Olgeirsson who just happens to be the President of the Spokane Canoe and Kayak Club. As an experienced kayaker Olgeirsson had the right equipment and knowledge to do the heavy lifting in the water and ensure the safety of all involved.
McArthur and Olgeirsson, with the help of another Avista employee, Ray Burnham, spent a lunch hour near the end of October on the project. On a crisp, clear day, Olgeirsson glided out to the island and attached a rope to the cart, while those on shore pulled it in. The whole deal took only 45 minutes.
Avista employees do an annual volunteer river clean up near the Mission Campus and regularly find large discarded items on Avista’s adopted mile of the Centennial Trail – shopping carts, tires and furniture included. Rarely do items make it so far into the river.
McArthur returned the cart to store employees, who promised to properly dispose of the wreckage.
Kudos to McArthur, Olgeirsson and Burnham for bettering the Spokane River for the community.
River users should be sure to follow all posted safety warning and closure signs on the water and especially near hydroelectric facilities. For more information about safety in the river and near dams, click here.
Sep 14 , 2011
Weirs are being built in the bed of the Spokane River downtown. What's a "weir" anyway?
I recently had the opportunity to visit the Aesthetic Flows Project taking place in the Spokane River’s North and Middle channels in downtown Spokane. I received special permission to step into the riverbed for the sake of capturing history in the making for Avista (I also relish opportunities to wear my hard hat).
The project is attracting a lot of attention from spectators passing by as contractors dressed in bright green T-shirts aim their large hose full of concrete-like material at oddly shaped structures formed out of rebar, which are called weirs. The manmade structures are designed to divert the water during low flow periods in a manner that is aesthetically pleasing and they are being made to match the existing river bed as closely as possible-both in color and texture. In fact, once the material has been applied, Land Expressions, our contractor has about two hours to transform the mud-like substance into natural looking weirs before they set up and become too hard to manipulate. They use tools like brushes, paint rollers, and shovels to make this happen. It’s quite impressive, a work of art really.
Typically, this stretch of the river (North and Middle Channels) doesn’t have a lot of water flowing through it during the summer months because river flows drop off after spring runoff. However, about this time next year, the water is expected to be flowing more evenly across both the North and Middle channels of the river near Canada Island with the addition of the weirs.
The work you see Avista doing isn’t just about looks, as the name suggests. It’s part of our new 50-year Federal Energy Regulatory Commission (FERC) license to operate our five hydroelectric facilities located on the Spokane River. The purpose of the Aesthetic Flows Project is to return the river’s channels to a more natural state, the way they were before early developers cut into the bedrock to divert water during dry times.
The project is expected to be completed by the end of October. Once this is done, there may not be another opportunity for me to don my hardhat in that stretch of the river for quite some time. In the slide show above, you can check out some of the recent photos of the project as it progresses.
If you have any questions about this project, please feel free to call Speed Fitzhugh, Avista’s Spokane River License Manager at, (509) 495-4998.
Sep 08 , 2011
If you happened to be in downtown Spokane over the weekend taking part in the festivities that go along with Pig Out in the Park, you may have noticed the large crane sitting near the Monroe Street dam as well as other projects taking place in and around the Spokane River.
|Removing accumulated rock and gravel from
Monroe Street Dam forebay. Enlarge photo.
The work is part of Avista’s 50-year Federal Energy Regulatory Commission (FERC) license to operate our five hydroelectric dams on the river and will help protect the resources and operations of our dams in order to generate clean, reliable and cost-effective hydropower for our customers.
This week, we started removing accumulated rock and gravel from the forebay, (the area that pools behind the dam) at Monroe Street and are relocating the materials back into the river below the dam. This is being done because the high river flows from this spring caused large amounts of rock, gravel and other materials to accumulate at the dam. The accumulated rock can damage the intake structure where water enters the turbine, thus interrupting clean and efficient power generation.
Before we were able to begin the project, we performed a bathymetry survey which illustrates the terrain under water so we know where the material has accumulated. We also sampled and tested the materials for contaminants to determine whether or not the rock and gravel could safely be placed back into the river below the dam. The testing and analysis of the sample materials was conducted by a third-party that determined the material was safe to relocate downstream. Once the rock removal is complete, we will perform a second bathymetry survey in order to calculate the total amount of material removed from the forebay.
Other projects that are highly visible to downtown visitors include the construction of a new viewing platform at Upper Falls and the Aesthetic Flows Project in the Upper Falls’ north and south channels. Look for more information about these projects
here on the blog as they continue to progress. In the meantime, if you would like additional information about Avista’s hydroelectric projects, please contact Speed Fitzhugh, Spokane River License Manager for Avista at, 509-495-4998.
Last year we did this video that showed the relocation of rock and gravel in action. Taken Aug. 2010.
Sep 06 , 2011
Drawdown to winter level begins on Tuesday after Labor Day
Avista is beginning its annual fall drawdown of Lake Coeur d’Alene Sept. 6. The lake will be gradually lowered approximately a foot from full pool by the end of September, and an additional 1½ feet per month thereafter until reaching its winter level. Property owners and boaters should take measures to secure docks and boats for the winter season during this period.
As part of Avista’s FERC license to operate its Spokane River Hydroelectric Project, which includes Post Falls Dam, Avista is required to maintain the level of Coeur d’Alene Lake at summer full-pool elevation of 2,128 feet from as early as practical in the spring until the Tuesday after Labor Day. (Read More).
Aug 29 , 2011
Workers place steel anchor bolts with high strength resin into the bedrock to create a solid foundation for the weirs
during our Spokane River aesthetic flows project in downtown Spokane.
Avista’s work on the aesthetic flows project in the river in downtown Spokane is getting a lot of attention from curious onlookers wondering what the project is all about. The reason behind the project isn’t just about looks as the name suggests. While the overall goal is to create a cascading waterfall effect through the channels of the Spokane River that run north and south of Canada Island, the work is related to the aesthetic spills requirement of our Federal Energy Regulatory Commission (FERC) license.
In 2009, Avista was issued a new 50-year license by FERC to operate our five hydroelectric dams on the Spokane River (Post Falls, Upper Falls, Monroe Street, Nine Mile and Long Lake). The purpose of the aesthetic flows project is to return the river’s channels to a more natural state, the way they were before early developers in Spokane cut into the bedrock to divert water during dry times.
The spray-painted dots you see on the riverbed (in the image above and to the right) are outlines for where the concrete weirs will be installed. Weirs are structures that divert water. Last year, Avista brought together several stakeholder groups, including the Washington Department of Ecology, The Sierra Club, and others, to take part in a pilot test for the project using sandbags as temporary weirs to divert the water. The feedback we received helped us determine the placement for the permanent weirs.
Our contractor is currently placing steel anchor bolts with high strength resin into the bedrock to create a solid foundation for the weirs. The weirs will be custom made to match the natural basalt bedrock as much as possible, including consideration for the existing terrain’s texture and color.
In addition to providing aesthetic attributes, the project will accommodate fish passage at various water flow levels that are determined by the Department of Fish and Wildlife and the Department of Ecology. During the project, fish biologists and contractors are on site, relocating fish safely downstream due to the river flow being temporarily stopped while the weirs are constructed.
Once the project is complete, water will flow more evenly throughout the two channels of the river and will produce a more pleasing flow of water through Riverfront Park. The project is expected to be complete by the end of October so you will most likely continue to see activity in the river channel throughout the fall.
Aug 11 , 2011
Whether you’re in downtown Spokane spending the afternoon at Riverfront Park or just happen to walk through the area on your lunch hour, you will see a number of projects taking place in and around the river between Upper Falls and Monroe Street Dams this summer and fall. The work will enhance fish, wildlife, water quality, recreation and aesthetic resources in our community and meet requirements of Avista’s Federal Energy Regulatory Commission (FERC) license to operate our dams on the Spokane River.
As flows drop to summer levels, the following projects will take place in and around the river. If you are in the area, you may see temporary work structures, cranes, trucks and contractors. All equipment will be handled and operated with an emphasis on public safety and protecting the environment. For your own safety, please stay out of the riverbed and keep clear of designated work areas.
Here’s what’s on the construction schedule:
Viewing Platform Construction – Upper Falls
Construction of a new viewing platform near Avista’s Upper Falls Dam in Riverfront Park will take place this summer and fall. Avista is building the platform to access the Upper Falls Dam for maintenance. Once the work is complete, park visitors will have a permanent spot to enjoy the views of the river. This project will also improve pedestrian access and the aesthetics at Riverfront Park.
Aesthetic Flows Project – north channel, Upper Falls
The goal of Avista’s aesthetic spills project is to spread water more evenly throughout the two channels of the Spokane River that run north and south of Canada Island and produce an aesthetically pleasing flow of water that viewers can enjoy throughout the year. To do this, we’ll modify the river’s channel in order to return it to a more natural state, the way it was before early developers in Spokane cut into the bedrock to collect water during dry times. This project Last year, Avista brought together several stakeholder groups, including the Washington Department of Ecology, The Sierra Club, and others, to take part in a pilot test for this project. Immediately before and during construction, Avista will not release flows into the channels to the north and south of Canada Island.
Monroe Street Dam rock removal
Generating clean, efficient power is a top priority at Avista. The high river flows this spring have caused large amounts of rocks, gravel and other materials to accumulate at the Monroe Street Dam. The excess debris can damage the intake structure and interfere with power production.
In September, the accumulated rocks and gravel will be removed from the forebay. Depending on the analysis of sampled material, the materials will then be placed back into the river below the dam. Usually this activity is done every two years, however, because of heavy water flows this year, Avista will be performing the work again this fall.
While fishery work may not be as visible as other activities, biologists will be doing work throughout the summer and fall in the Upper Falls and Nine Mile Reservoirs. The majority of the work this fall will involve a study to determine the population of fish in this area of the Spokane River.
In 2011, Avista will plant 6,000 catchable, sterile rainbow trout in Upper Falls Reservoir and 9,000 fish in Nine Mile Reservoir. This stocking program is intended to provide families in our community the opportunity to fish.
Stay tuned for more information about these exciting projects throughout the summer and fall. Avista has also posted signs near the project areas to educate those who pass by about what we’re doing.
Jul 27 , 2011
The Spokane River is one of the most striking and scenic centerpieces of our community. It has a rich cultural history, and provides habitat for fish and other aquatic life as well as an abundance of recreational activities.
At Avista, we work hard to be good stewards of this vital resource as we operate our dams to provide clean, reliable, and cost effective energy to our customers. Today, we sent out the first issue of the Spokane River Newsletter, a quarterly publication that will be distributed to those who are interested in learning more about our activities in and around the Spokane River. The newsletter will not only keep you informed about current news, but it will introduce you to some of the people who take care of our natural resources. Each season, Avista plans to distribute the newsletter to stakeholders, employees, customers and others who sign up for it
Jul 19 , 2011
Water levels allow spill gates at Post Falls Dam to be closed
The Post Falls Dam spill gates during high water runoff.
Photo courtesy of Avista employee Patty Hanson.
Avista is advising Spokane River users that river recreation is now permitted in the area between the Spokane Street Bridge and the boat restraining systems located just upstream of the Post Falls Dam. River flows have dropped sufficiently to allow all of the spill gates at the hydroelectric facility to be closed.
The City of Post Falls boat launch at Q’emiln Park was opened to the public Monday, July 18. Typically this occurs sometime between Memorial Day and the July 4 holiday. The median date for closing the gates is June 22. This year, cool spring temperatures and a lingering, heavy snowpack caused longer than normal high water flows, which delayed the opening of the boat launch.
Avista expects summer operation at the dam to continue through Labor Day, as long as weather conditions allow. River users are cautioned that weather conditions can cause rapid changes in water levels. Please exercise caution when using the waterways.
For current information on anticipated elevation changes on Coeur d’ Alene Lake, Lake Spokane, and the Spokane River, to call Avista’s 24-hour telephone information line. In Idaho, call (208) 769-1357; in Washington, call (509) 495-8043. The recorded information is provided to advise shoreline property owners, commercial and recreational users of changes in lake and river elevation levels that may affect plans for water use. You can also check weather and water flow information here.