Dams

Swan Falls Hydroelectric Dam on the Snake River in Ada and Owyhee counties, is 107 feet tall and 116 years old. Fish passage built into this dam was a failure, making it the first dam on the Snake to block migrating salmon and steelhead. Note that the failure of the fish passage did not cause the dam to be dismantled. Salmon and steelhead just lost significant spawning ground.

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A recent e-copy of WyoFile had an article on a new proposed irrigation impoundment for south-central Wyoming. Unlike most impoundment projects that are justified through multiple benefits to society, this proposal will serve about 100 irrigators and will not generate electricity or provide drinking water, and most of the recreation will be privately controlled. It will cost Wyoming taxpayers about $72 million with the benefiting irrigators carrying another $8 million.

Ecological consequences are not addressed in the article other than to mention a predicted improvement in the fishing downstream of the dam because of proposed minimum flow requirements. The proposed dam is part of Wyoming governor Matt Mead’s initiative, 10 in 10—a new irrigation dam a year for the next ten years. This dam is only ten air miles from a similar dam already in place in the same watershed.

The science of dam impacts is well known so it is surprising that Wyoming is promoting such an ambitious initiative. Across the country, similar dams are being removed at a rate of dozens a year. According to the organization, American Rivers, almost 1,400 dams had been removed nationwide since 1900, the vast majority since 1990.  Twenty-six dams were removed in 2016 alone. By 2020, over 70 percent of America’s remaining 75,000 dams over six feet tall will be over 50 years old. Most dams have a lifespan of only 100 years and repairs of hazardous conditions lag well behind identified safety issues. Dam safety experts say that 4,400 dams are in critical need of repair at a cost of over $50 billion.

Eastern Idaho has firsthand experience with the aftermath of a dam failure. When Teton Dam collapsed, it left a wave of death and property damage that reached all the way to Idaho Falls. One government report states that full recovery of the habitat in the impounded area may take 100 years. Other areas will not recover at all without significant engineering.

Here are a few negative ecological consequences of constructing a dam across a free-flowing river.

1.       The dam creates an insurmountable barrier to movement. Fish and other aquatic species do not get past dams without help.

2.       Water that leaves the impoundment may be too warm if it comes from the top and too cold if it comes from the bottom, influencing the productivity of the river below for several miles.

3.       Impoundments flood habitat. In the West that means riparian habitat, the rarest and most biologically diverse of any western habitat.

4.       The dams almost completely stop sediment transport downstream and these same sediments build quickly behind the dams, shortening their effective lifespan.

 

Downstream, the situation can be even more dire and the impacts may extend for hundreds of miles. This is a complex topic so suffice it to say that the impacts are often unique to each downstream system but always have to do with two things: lack of a sediment source and/or the flattening of the hydrograph or annual flood cycle. Sediments, floods and droughts, stressors the system has evolved with, are mostly gone. These changes can cause channel scouring to bedrock, channel narrowing, vegetation shifts and thwart habitat building along shores and islands.

Now that people better understand many of the true impacts of dam building, it seems to me that society rarely benefits from an impoundment as much as we lose. Citizens, however, are rarely given the chance for true involvement in the issue. That is too bad, because such things are far too important to trust to politicians.

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Wildlife License Plates

Great news! as of 2024, there are three NEW designs for license plates. They still are bluebird, cutthroat trout and elk, but they are beautiful.

Idaho Wildlife license plates provide essential funding that benefits the great diversity of native plants and wildlife that are not hunted, fished or trapped—over 10,000 species or 98% of Idaho’s species diversity. Game species that share the same habitats (such as elk, deer, antelope, sage-grouse, salmon, trout) also benefit from these specialty plates.

No state tax dollars are provided for wildlife diversity, conservation education and recreation programs. Neither are any revenues from the sale of hunting or fishing licenses spent on nongame species. Instead, these species depend on direct donations, federal grants, fundraising initiatives—and the Idaho Wildlife license plates.

Both my vehicles have Bluebird Plates. I prefer the bluebird because the nongame program gets 70 percent of the money from bluebird plates, but only 60 percent of the money from elk and trout plates - 10 percent of the money from elk plates supports wildlife disease monitoring and testing programs (to benefit the livestock industry) and 10 percent from cutthroat plates supports non-motorized boat access.

Incidentally, in 2014, the Idaho Legislature denied the Department of Fish and Game the ability to add new plates or even to change the name of the elk and cutthroat plates (very specific) to wildlife and fish plates, a move that would have allowed for changing images occasionally and generating more revenue. It would seem that they believe that we Idahoans don't want a well funded wildlife program.

I think it is time we let the Legislature know that Idahoan support wildlife funding and that we would like to see these generic plates come to fruition.