Do Dams Still Have a Place in Modern Infrastructure?
In February (2017), some 200,000 residents near Oroville, California, roughly 70 miles north of Sacramento, were ordered to evacuate their homes. The Oroville Dam, looming above the city mere miles away, was in serious danger of breaching. Further complicating this issue was the fact that the main spillway designed to deal with overflow had been damaged severely, leaving a yet-to-be-used emergency spillway as the only preventative measure of stopping potentially massive, down valley flooding.
Fortunately, the abnormally heavy rainfall the area had been experiencing subsided; water levels dropped slightly and the emergency spillway provided enough relief to avoid catastrophic damage and the potential loss of human life. Though the situation could have been dire, it served to highlight America’s deteriorating infrastructure and the ongoing debate regarding the actual value of dams and whether the benefits they provide outweigh the damage they cause.
The potential for harm to humans is particularly noteworthy when these dams fail or threaten to fail. There are several examples of dam failures with devastating loss of life. However, even in the most placid of times, dams often have a severe impact on our natural world, as well. The effects of dams on the environment are numerous and varied; most notably, they interfere with natural water flow, degrade water quality, and impact the habitats of these waterways, vastly altering animal and plant life in their ecosystems.
Placing a barricade across waterways, for example, directly impacts the ability of native fish to navigate these rivers and affects their migratory patterns and spawning. Even with fish ladders, or other methods of assisting with migration, dams severely impact the ability for fish to exist in their natural habitat. International Rivers offers a lengthy explanation of the impact of dams on fish — too lengthy to adequately cover here — however, in short, the impact is significant and affects other animals, as well as humans, which rely on fish migration for their own survival.
Additionally, dams stop the flow of sediment to downstream ecosystems and river outlets. This sediment is critical to naturally replenish these systems and ends up sinking to the bottom of the reservoir when halted by a dam. To compensate for the lack of sediment, rivers have shown an ability to gather sediment by eroding the riverbeds and banks downstream. This erosion affects nearby plant life, fish habitats, and even human water collection. Additionally, according to International Rivers, the creation of reservoirs, the resulting sediment collection, and altered ecosystems, especially in the tropics, can actually create greenhouse gasses at levels on par with the aviation industry.
The idea of massive infrastructure investment and rehabilitation in the United States is a noble and necessary one, worthy of unified praise. And yet, the question remains: should we spend massive amounts of funds on dam maintenance and repair rather than starting the long process of dam removal? Dam removal may be costly as well, but one could argue that the benefits of dam removal justify this focus rather than simply repairing this aging, and often harmful, form of energy production and nature interference.
Although most the nation’s largest dams are owned and operated by the federal government, approximately 56% of dams in the United States are privately owned, according to FEMA. The massive government infrastructure investment could include these privately owned dams, but it is not guaranteed. This responsibility falls, then, on the private owners who may be less inclined to spend large sums of money on preventative or repair maintenance. The threat to human population centers near these dams is all too real and disconcerting. Damage to property, in addition to the potential loss of life, is, of course, the priority and the main justification for investment. However, the emphasis here is on the environmental effects of dams and why dam removal should be our focus moving forward.
The irony of environmental advocates arguing for the removal of sources of clean energy production is noteworthy. However, it is just as ironic to protect a source of clean energy production that harms the very environment we are trying to protect. The environmental impact of dams should be considered in any evaluation; should governments choose to prioritize other sources of clean energy, there exists more than enough energy production to offset the losses from dam removal. Though hydroelectric energy produced by dams is considered crucial, in actuality it accounts for a very small percentage of energy production.
According to the United States Geological Survey’s Water Science School, renewable energy accounted for only 10% of the nation’s energy production in 2015. Of that 10%, hydroelectric energy accounted for only 26% (7% of the total energy production). Wind, solar, and geothermal combined produced 24% of the nation’s renewable energy. These numbers show the growth potential in other sources of clean energy and focusing our infrastructure investments in those sources could replace most of the hydroelectric production, increasing the overall contribution of renewable energy. Given the harm caused by dams, and the potential for alternative sources of energy production, can we still justify the existence of many of these dams?
Clearly, there is a choice to be made. We can continue to put funds towards repairing, staffing, and maintaining dams; or, we can choose to shift our focus towards other, less environmentally-impactful sources of energy production to begin the slow process of removing unnecessary dams. There are certainly reasons to support dams, such as flood control and irrigation for farmers; thus, each dam must be evaluated individually in an effort to assess its structural cohesiveness, its impact on humans and wildlife, and whether the benefits of each particular dam outweigh their costs.
If the risks outweigh the rewards, the decision should perhaps be whether it any given dam could be removed. Recent examples — such as the Elwha and Glines Canyon Dams in the state of Washington — show there are justifiable and positive dam removal projects. Of the roughly 90,000 American dams listed by the National Inventory of Dams, only 2,114 are noted as having the primary purpose of producing hydroelectric power. In contrast, more than 25,000 are listed as having the primary purpose of human recreation. Clearly, some dams serve an important purpose, but many more could plausibly be removed. It is a vitally important environmental issue, one which requires thoughtful decision-making that will have long-lasting effects both for humans and our environment. It is a conversation we must continue to have.