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Aug 25 , 2010
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The evaluation team takes a look at the river from one of 10 public viewpoints Wednesday morning,
August 25. The group will suggest changes to the temporary dams and come back for a second and
possibly third look at spills through the two channels. Evaluators include representatives of Spokane Parks
and Recreation, Spokane Canoe and Kayak Club, Sierra Club, Washington Department of Ecology, Center
for Environmental Law and Policy, Avista, Friends of the Falls, and others. |
Normally at this time of the year, the north and middle channels of the Spokane River in downtown Spokane, what many of us know as Spokane Falls, look pretty dry. That’s because in the past during the dry summer months, natural conditions and Avista’s hydropower operations have resulted in little or no flow through that part of the river. That all changed last year with the issuance of Avista’s new 50-year Federal Energy Regulatory license to operate our Spokane River Project, which includes Upper Falls and Monroe Street Dams in downtown Spokane. As a result of the relicensing process, we must now release minimum aesthetic spills around the clock at both Upper Falls and Monroe Street. That began this summer, and you may have noticed more water flowing through the falls in July and early August.
But there’s more to it than that. If you’ve been to Riverfront Park in the past couple of weeks, you’ve probably noticed something else in the river. Cranes, sandbags, and workers have been busy preparing for an aesthetic spills pilot test at Upper Falls Dam. This test will help us determine whether permanent channel modifications can be made to bring the riverbed closer to its natural state, the way it was before early developers in Spokane cut into the bedrock to divert the water during dry times. We’re hoping to enhance aesthetic appeal even more during periods of low river flow. Our license requires us to do this study to learn whether the same, or a better, aesthetic effect can achieved with daytime releases of 300cfs and channel modifications, as the current daytime release of 500 cfs does, without modifications.
Avista’s Upper Falls Dam is located where the river splits into two channels around Havermale Island in Riverfront Park. The southernmost channel forms the forebay that provides water to the powerhouse, and the northern channel passes through the control works dam and splits again into two smaller channels that run north and south of Canada Island. These are referred to as the north and south (or middle) channels. These two channels are where the pilot test is occurring, and we hope that as a result of this work, viewers of the river downtown will have a pleasant experience no matter what time of year it is.
Last week we temporarily interrupted normal aesthetic spills and placed several small, temporary dams made with sandbags, called weirs, throughout the channels. These weirs divert the flow of water throughout the channels, and this week, an evaluation team made up of representatives of stakeholders, agencies and the public is viewing test spills and giving their feedback as we release 300 cfs through the two channels. Team members will make judgments based on their sense of sound, coverage, depth and power of the water as it moves through the channels. The feedback we receive will help us determine whether to move forward with permanent channel modifications next year.
Next week, we’ll remove all of the equipment and materials from the river, and we’ll return to normal aesthetic spills the following week. Then, if the outcome of the pilot test shows us that permanent modifications are the way to go, the real work begins.
So far, we’re excited about the potential of this project. We’re hoping the result is a cascading waterfall effect throughout both channels of the river that visitors and the community can enjoy all summer long. And this collaborative effort could indeed accomplish that, possibly restoring at least some of the river’s natural beauty that was lost through the development of Spokane over the past 100 or more years.
Jul 19 , 2010
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The Spokane River through downtown Spokane. |
One year into our new FERC license on the river, big projects happening
Watch for activity on the downtown Spokane stretch of the Spokane River beginning this week, as Avista starts work on several projects to protect and enhance fish, wildlife, water quality, recreation, cultural and aesthetic resources related to our Spokane River hydroelectric project.
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Click to view a map of the activities happening on
the Spokane River. | Over the next few months, visitors to the stretch of the river between Upper Falls and Monroe Street Dams will see equipment and temporary work structures in and around the river, including a crane near the river above Monroe Street Dam, intermittent aesthetic flows at Upper Falls Dam, sandbags, water bladders and moving equipment in the Upper Falls area. All of the equipment will be handled and operated with an emphasis on public safety and protecting the surrounding environment.
Work taking place includes a pilot study in the north channel of the river to learn what modifications can be made in order to return the river to a more natural state, and removal of accumulated rock, gravel and sediment at Monroe Street Dam. The work will begin in July and August as flows drop to their summer levels, and could be extended into early autumn.
While fishery work may not be as visible as other activities, it’s just as important. While we’re studying the river channel, biologists and contractors will be working in the stretch of the river between Upper Falls Reservoir and Monroe Street Dam, primarily on a study to assess whether fish can become trapped or stranded in the north channel of the river when water levels are low.
In late June, 3,000 catchable, sterile rainbow trout were planted in Upper Falls Reservoir. Another 3,000 fish will be planted in Upper Falls Reservoir this fall. The first year of a three-year fish population assessment will also be conducted in the Upper Falls Reservoir this fall.
Watch for updates as we progress, and see the attached map and handout for specific details, locations and approximate dates/timelines.
A year into the 50-year Federal Energy Regulatory Commission license to operate our five hydroelectric dams on the Spokane River (Post Falls, Upper Falls, Monroe Street, Nine Mile Falls and Long Lake), the work Avista will do is just getting started. These significant environmental measures will benefit both the communities and the natural resources where our facilities are located. Protecting resources and responsibly operating our dams helps us continue to generate low-cost, renewable hydroelectric energy. Jul 16 , 2010
The installation of new operable spillgates at Nine Mile Dam began this week as Avista finished drawing down Nine Mile Reservoir Thursday to allow a work barge and crew to begin. The upgraded system will allow Avista to pre-program desired heights and give operators the ability to raise and lower the height of the spillway at any time, incrementally if needed, in order to maintain the reservoir pool at a more constant level throughout the entire year.
The reservoir level must be lowered during construction to allow the contractor to erect the new spillgates. During construction, the pool level will be 2 to 4 feet below the spillway crest (about 12-14 feet below full pool), which may be lower than what it has been in the past when the flashboards were erected each year in mid-summer.
As a side note, to announce this news, this week we used a new e-mail tool for communicating directly with customers, river users, property owners and stakeholders interested in operational and environmental activities related to our Spokane River Project. This is one more way we’ll try to get information about river and reservoir levels, stewardship work and other river operations to folks quickly and directly. If you’re interested in being part of Avista’s mailing list for Spokane River News, send an e-mail to spokanerivernews@avistacorp.com. Jul 06 , 2010 Water levels allow spill gates at Post Falls Dam to be closed
Avista is advising Spokane River users that river recreation is now permitted in the area between the Spokane Street Bridge and the Post Falls Dam. River volumes have dropped sufficiently to allow the spill gates at the dam to be closed.
The City of Post Falls boat launch at Q’emiln Park is expected to be opened to the public today. Typically this occurs sometime between Memorial Day and the July 4 holiday. The median date for closing the gates is June 22; however the date has occurred as late as July 8 in 2008 and as early as May 22 in 2005.
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 Spokane River flows and Coeur d'Alene Lake elevation (includes anticipated changes in flow and elevation for the coming week) call 208-769-1357. For information on Spokane River flows and Lake Spokane elevation (includes anticipated changes in flow and elevation for the coming week) call 509-495-8043.
Jul 06 , 2010
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First edition of the Clark Fork Project Newsletter. | Post by Anna Scarlett
Avista’s two hydroelectric dams on the Clark Fork River, Cabinet Gorge and Noxon Rapids, generate more than 80 percent of the clean, renewable hydropower that we generate for our customers throughout Idaho and Washington. Last year marked the 50th anniversary of the first power generated at Noxon Rapids, our largest hydro facility and, arguably, the most impressive.
In addition to the daily work of operating of these impressive plants, more than 40 employees work with dozens of stakeholders to protect the natural resources around them, and help contribute to the communities and the economy of northern Idaho and Montana through their efforts.
Want to know more? We’ve launched a quarterly newsletter highlighting our operations and environmental activities and spotlighting employees and individuals doing this important daily work. Each season, we plan to distribute the newsletter stakeholders, Avista employees, customers and others who sign up for it. Take a look here.
Jun 21 , 2010
Heavy rains require action, lowering of river
Avista will need to open additional gates at the Post Falls Dam today to allow the increased flow in the Spokane River to pass by the dam. This action is due to a large amount of rain in the North Idaho mountains over the last 24 hours which is causing Coeur d’Alene Lake to rise.
Avista is waiting to open the biggest gate until this afternoon to allow Spokane River users to move their boats and equipment to a safe location in the river. The elevation of the river near the Spokane Street Bridge this morning is about 2,124.8 ft., which is about 3 feet below summer level. Once the bigger spill gate is opened the river level will drop as much as 7 feet below summer level.
Coeur d’Alene Lake is currently slightly above its normal summer level of 2,128 ft. above sea level which Avista is required to maintain until after Labor Day.
As more water flows in the Spokane River between the lake and the dam, Avista must open more spill gates to allow the water to pass so that the lake remains at or near 2,128. The more spill gates that are open, the lower the elevation of the water above the dam, near the Spokane Street Bridge.
Boaters and other river users are reminded that weather conditions can cause rapid changes in river levels. Please exercise caution on the water.
Jun 17 , 2010
This summer and fall, Avista will replace the wooden flashboards at Nine Mile Hydroelectric Development with operable spillgates. The upgraded system will allow Avista to pre-program desired heights and give operators the ability to raise and lower the height of the spillway at any time, incrementally if needed, so that we can maintain the reservoir pool at a more constant level throughout the entire year.
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Click above to enlarge graphic. |
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Click above to enlarge graphic. | What will the new spillway consist of?
The new spillway will consist of metal gates supported by air-filled rubber bladders. Compressors will inflate the bladders to approximately 25 psi to raise the gates. When stream flows are high enough, the bladders will deflate to lower the gates so water can flow over the top. The new, automated technology will be much more flexible and precise when managing the reservoir elevation.
What is the construction plan and timeline?
While the timeline is subject to change, the construction period is anticipated to be from July through October 2010. The new spillgates have been ordered and we expect delivery in July.
Once the new spillgates are delivered, we will remove some concrete from the top of the existing dam and replace it with new concrete to provide a good foundation to erect the new gates. A trough will be excavated in the dam crest for the compressed air lines that will be used to inflate the bladders.
The reservoir level must be lowered during construction to erect the new spillgates. During this period, the pool level will be 2 to 4 feet below the spillway crest, which may bring the level lower than what it has been in the past when the flashboards were erected each year in mid-summer. Construction should be complete and the reservoir level back to full pool by November of 2010.
How will the new spillway change Nine Mile operations?
No change in the full pool level is planned after the new spillway is installed. To the extent possible, we will maintain the reservoir level at the normal full pool elevation year around.
In the past the reservoir had to be lowered each summer to accommodate installation of the flashboards. When the flashboards were pulled in early winter or spring of each year, the material was lost and had to be replaced. Additionally, erecting the wooden flashboards each year is a labor intensive operation. The new spillway will result in less regular maintenance for Avista and enable the generation of additional power.
For project information, contact Steve Schultz, Project Manager, Senior Engineer. Jun 07 , 2010
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Post Falls Dam on the Spokane River. |
This has been quite a year for unusual weather. All the rain we’ve had is increasing the flow of water into Coeur d’Alene Lake. Our federal license doesn’t permit us to let the lake go above its summer level of 2,128 ft. above sea level. So to keep that from happening we’ve been letting as much water as possible spill over the dam at Post Falls. When the river runs fast, as it is now, this causes the water level to drop in the stretch of the Spokane River upstream of the dam.
If the weather cooperates the river should start to rise later this week. And even though this is an unusual year for weather, it’s normal for the river to fluctuate until around the Fourth of July, when we are typically able to close the spill gates at the dam and hold the lake level steady.
We’re looking at some ways to improve communications with river users, but please remember that conditions can change very quickly and use caution on the water.
-For current information on Spokane River flows and Coeur d'Alene Lake elevation (includes anticipated changes in flow and elevation for the coming week) call 208-769-1357.
-For current information on Spokane River flows and Lake Spokane elevation (includes anticipated changes in flow and elevation for the coming week) call 509-495-8043.
Apr 21 , 2010
We're always pleased when we can get out the word about safety on the bodies of water that our dams are connected with. Yesterday, KXLY reporter Jeff Humphrey did a good story on Avista raising the levels on Lake Coeur d'Alene in conjunction with low spring runoff.
If you're a recreational boater, that might mean you'll be able to use the lake earlier than in previous years. But with these early changes comes the dangers hidden under the water - such as rocks or wooden pilings, so watch out.
Apr 03 , 2010
Years ago, I spent a few summers boating the St. Joe River and lower part of Coeur d’Alene Lake, which includes Chatcolet, Round, Benewah and Hidden Lakes. In fact, I learned to water-ski on the St. Joe, known for its glass-smooth surface and calm waters. In those days I didn’t give much thought to the river banks – beyond wondering where exactly the river ends and the lake begins.
Last week, I had the enlightening experience of seeing first-hand some of the long-term impacts of hydroelectricity, boating and other uses of the lake and river, when I joined a group touring a two-year shoreline erosion inventory and assessment on the St. Joe River where it flows through this lower portion of Coeur d’Alene Lake.
Avista and the Coeur d’Alene tribe are working together on this erosion study, one of the first of three major phases in our erosion measures within the Tribal waters of Coeur d’Alene Lake, and a condition of Avista’s 50-year FERC license to operate its Spokane River hydroelectric project. The study is also part of the comprehensive settlement reached between Avista and the Coeur d’Alene tribe prior to last year’s issuance of the license. In addition to compensating the Tribe for past and future storage of water, the settlement requires Avista to pay a total of $100 million into the Coeur d’Alene resource protection trust fund for costs associated with environmental measures in and around Coeur d’Alene Lake. This funding mechanism allows the Tribe and Avista to collaborate on complying with license requirements, which include this shoreline erosion control project, as well as activities in wetland restoration, water quality monitoring, aquatic weed management and protection of cultural resources on the reservation.
Dave Lamb of the Coeur d’Alene Tribe and Bruce Stoker of Earth Systems, consultants to Avista on the erosion inventory and assessment, showed a group including Avista’s Meghan Lunney, Becky Kramer from the Spokesman-Review and myself just how much the banks of this part of the St. Joe have eroded over the years, primarily due to the wave action caused by boats in high water. Bruce Gardipie, a member of the Kootenai, Salish and Confederated Tribes of Montana, who has lived on the Coeur d’Alene Reservation for 40 years, was our boat operator, and provided additional expertise.
I never even knew where the actual channel of the St. Joe ran, let alone that recreationists like myself could potentially contribute to its erosion. It was an eye-opener, and a good learning experience.
Now that the Spokane River FERC license has been issued, it’s great to see the work beginning, and it’s even better to see years of planning resulting in people working together to protect and improve the environment. This is just one of the many protection, mitigation and enhancement measures that we will implement in collaboration with the Tribe as part of our license and our ongoing commitment to protect natural resources associated with our hydroelectric projects.
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