Last week the Federal Energy Regulatory Commission (FERC) provided notice to the public that is ready to perform environmental reviews of the proposed Clark Canyon Dam Hydroelectric Project, sited at the Beaverhead River’s headwaters outside Dillon, MT.
Anyone interested in providing comments, recommendations, terms and conditions, or prescriptions concerning the proposal has 30 days – until March 24th, 2016 – to send their thoughts to FERC.
At the bottom of this page we’ve provided two ways for you to tell FERC to Protect the Beaverhead.
The Clark Canyon Dam Hydroelectric Project would utilize the existing, U.S. Bureau of Reclamation’s Clark Canyon Dam and outlet works, including an intake structure and concrete conduit in the reservoir. The project would consist of the following new facilities:
(1) a 360-foot-long, 8-foot-diameter steel penstock within the existing concrete conduit, ending in a trifurcation;
(2) two 35-foot-long, 8-foot-diameter penstocks extending from the trifurcation to the powerhouse, transitioning to 6-foot-diameter before entering the powerhouse;
(3) a 10-foot-long, 8-foot-diameter steel penstock leaving the trifurcation and ending in a 7-foot-diameter cone valve and reducer to control discharge into the existing outlet stilling basin;
(4) a 65-foot-long, 46-foot-wide reinforced concrete powerhouse containing two vertical Francis-type turbine/generator units with a total capacity of 4.7 megawatts;
(5) two 25-foot-long steel draft tubes transitioning to concrete draft tube/tailrace section;
(6) a 17-foot-long, 15-foot-diameter tailrace channel connecting with the existing spillway stilling basin;
(7) a 45-foot-long, 10-foot-wide aeration basin downstream of the powerhouse with three frames containing 330 diffusers; (8) a 1,100-foot-long, 4.16-kilovolt (kV) buried transmission line from the powerhouse to a substation;
(9) a substation containing step-up transformers and switchgear;
(10) a 7.9- mile-long, 69-kV transmission line extending from the project substation to the Peterson Flat substation (the point of interconnection); and
(11) appurtenant facilities.
The estimated annual generation of the Clark Canyon Dam Project would be 15.4 gigawatt- hours. All project facilities would be located on federal lands owned by the U.S. Bureau of Reclamation and the U.S. Bureau of Land Management. The applicant proposes to operate the project as run-of-release.
(Photo: Brian Wheeler)
Why Is This Proposal Important?
- Changes in Flow: Water from CC Dam supports a diverse number of uses, including both traditional agriculture and a strong local recreational-based fishing and boating economy. A new hydroelectric facility means, practically speaking, that operators have the ability to regulate how much water escapes the dam. The CC Hydro proposal states that it intends to operate the dam as a “run of release” facility, meaning no change in flow regimes from those traditionally seen for irrigation and drought storage purposes.
FERC’s environmental analysis should pin down, precisely, (1) what “run of release” will mean in terms of seasonal flows from the Project; (2) best available science concerning necessary flow levels for fisheries health in the Upper Beaverhead; and (3) the estimated scope, timing, and seasonal trends of senior water right withdrawals from the Upper Beaverhead. A final license should balance these interests to both support senior water rights and the important local fishery and river health.
- Fisheries Impacts: Operation of CC Dam – and particularly a new hydro facility – can create problems for downstream fisheries. (1) If water from the Project – whether escaping over the spillway, through turbines, or via aeration units – is supersaturated, fish can absorb too much nitrogen in their blood, giving them what divers call the “bends,” and at extreme levels even killing fish. (2) Conversely, if mechanical blowers at the Project fail to sufficiently oxygenate water, dissolved oxygen levels will plummet, also harming or in extreme cases killing fish. (3) Depending on where water for hydro is withdrawn (bottom vs top of reservoir), too cold or too warm water can also hurt downstream fish. Last, (4) hydro releases can contribute unnatural turbidity, meaning water downstream loose clarity, which can harm fish’s ability to forage.
FERC’s environmental analysis should thoroughly examine how the applicant will protect downstream fisheries and ensure adequate plans are in place that maintain healthy levels of dissolved oxygen, dissolved gas, temperature, and turbidity.
- Water Quality Impacts from the Reservoir: The reservoir CC Dam creates is the reason the Beaverhead River as we know it today exists. (1) Reservoirs can significantly slow the rate at which water is moving downstream, increasing surface water’s ability to absorb heat from the sun. Colder water sinks toward the bottom because of its higher density in a layering effect called stratification. When stratification occurs, the colder water that sinks toward the bottom contains reduced oxygen levels. If water is released from the colder, oxygen-depleted depths, downstream habitat conditions can be negatively impacted because those discharges will contain low dissolved oxygen levels. Reservoirs also often trap (2) sediments, which are fine organic and inorganic materials typically suspended in the water. When sediments collect, an effect called “nutrient loading”can de-oxygenate the water column. This happens because more nutrients are available, thus more organisms populate the area to consume the nutrients, and more oxygen is used, depleting the supply of oxygen in the reservoir.Preliminary science from 2014 and 2015 indicates that CC Dam experienced both destratification and nutrient loading, resulting in poor water quality, turbidity, and bad fishing all the way down the Beaverhead to Barretts Diversion. Read more about those events by clicking here. FERC’s environmental analysis should examine best available science about these recent pollution events and, in combination with analysis of proposed operation plans of the hydroelectric facility, determine whether the Project has the potential to contribute to or worsen these water quality problems.
- Economic Impacts: CC Dam and the Beaverhead River support two important, local agricultural and recreational economies. Senior water right owners use cool, clean flows to water crops and stock, and dozens of local businesses depend on cool, clean flows to maintain the renown Beaverhead fishery that brings thousands of people, and significant economic development, to the region. If the hydro project negatively affects local water quality in the downstream Beaverhead, both local economies could suffer.
FERC’s environmental analysis should examine the potential for hydro operations to degrade local water quality and in turn, the corollary economic consequences.
Click here to download the FACT SHEET!
Take Action Before March 23rd, 2016:
Everyone who cares about the Beaverhead has the right to submit comments to FERC urging them to carefully consider the hydro proposal and its potential to cause, contribute to, or exacerbate environmental issues. Your comments to FERC are critical to ensuring any final hydropower license contains science-based conditions that protect the river, fisheries, and important local economies!
It is very important that the public make their voice heard now. FERC agreed to waive normal environmental review procedures or requests for additional, necessary scientific studies because it believes all relevant environmental issues are known and have been adequately studied.
- Click here to read FERC’s December 2015 Notice waiving substantive public participation rights and expediting environmental review timelines.
However, all relevant science isn’t being considered! Neither FERC nor the applicant are looking at emerging science detailing recent, harmful algal blooms and clarity problems on the Upper Beaverhead during 2014 and 2015, or examining the potential of a new hydropower facility to contribute to or worsen those water quality problems.
This means the current public comment period is the only near-term opportunity citizens have to weigh-in on FERC’s review of the proposed Clark Canyon Hydroelectric Facility.
Please take 10 minutes, do Three Easy Steps to send FERC a letter, then Sign the Petition.
Submit a Comment to FERC:
- STEP ONE: Click here to download a draft comment letter outlining the issues FERC needs to consider in its Project reviews. Please consider personalizing your letter!
- STEP TWO: Click here to go to FERC’s eComment web portal. On the web portal, click the orange comment box; you will be redirected to a second webpage where you’ll need to enter your name and email (you’re not registering for anything…) Once you submit that information FERC will send you a personal link to access the comment system.
- STEP THREE: Open your personalized comment letter from Step One. Copy-Paste your letter into the eComment text box. Read it through one more time for accuracy, then click Submit.