A Big Dam Problem
By Stephen Tuttle | May 30, 2020
We have a serious dam problem.
There are about 90,000 dams in the United States. The number is sketchy because the U.S. government only operates and maintains 1,500 of them, and the rest are operated by the state or private entities. Most are at least 60 years old, and failures are not uncommon. Since 1980, there have been an average of 24 dam failures a year, with at least one fatality and nearly all causing property damage.
According to the National Survey of Dams, more than 14,000 U.S. dams, with 10 million people in the flood plain below them, have a high potential for “failure causing fatalities.” Of those, some 2,300 are considered an extreme hazard needing immediate repair.
You'd think every state would be more than a little concerned and make dam safety a high priority. You would be wrong. It's seems to be less than a low priority.
We had a good taste of that recently when the Edenville dam north of Midland, which had previous structural violations, failed, and the Sanford dam downstream nearly did. More than 10,000 people were evacuated, and the resulting flooding did tens of millions of dollars of damage.
Those are just two of Michigan's 2,500 dams. Our dam safety department? Two inspectors, a supervisor, and a budget of less than $400,000. We're hardly alone.
For example, Oklahoma has three inspectors for nearly 5,000 dams, Iowa has three for about 4,000. Alabama, which has nearly 2,700 dams, has no inspectors or dam safety program at all; they consider it unnecessary government regulation.
California is the gold standard of dam safety, with a $21 million annual budget. But that didn't help much when the poorly engineered Oroville dam spillways collapsed, forcing the evacuation of 110,000 people downstream.
We don't fix dams unless they are on the verge of collapse or have already failed. States, which are primarily responsible for dam safety, don't much like the price tag. But by constantly delaying what needs to be done, we've made the price tag increase exponentially.
The American Society of Civil Engineers puts the cost to fix them all at $64 billion. The Association of State Dam Safety Officials says it will be closer to $71 billion. Just fixing those posing the greatest threat to human life would approach $10 billion. Repairs to the the Oroville spillway alone will cost at least $1.1 billion. But we aren't really fixing any of them unless we absolutely must.
This dovetails nicely with the environmental movement calling for the removal of dams. Last year, 99 dams, mostly small, were removed in an effort to return rivers to their natural state. But even that isn't cheap or safe.
When they were removing the Brown Bridge dam here, a failure of the temporary river diversion sent most of Brown Bridge pond cascading downriver, damaging or destroying 66 properties.
Removal of larger hydroelectric dams is expensive, requiring a significant commitment from state budget writers. The Glines Canyon Dam, in Washington state, cost $60 million to fully remove — part of a $350 million river restoration project.
Many now argue the Glen Canyon dam on the Colorado River should be decommissioned and removed. It creates the Lake Powell reservoir, the second largest in the country, and provides electricity to about 6 million homeowners and businesses. But the dam has changed the downstream ecology for the worse, Lake Powell fills spectacular Glen Canyon, and loses huge amounts to evaporation. Both Lake Powell and Lake Mead, impounded by Hoover Dam, are at half-capacity, so draining the former and filling the latter makes some sense.
But Colorado River water, promised to seven states, four tribal nations, and Mexico, is controlled by the Colorado River Compact, and Lake Powell is part of the Compact. It would take an act of Congress and agreement from all 12 stakeholders to decommission any of the Colorado River dams, of which there are 15, with literally hundreds more of various shapes and sizes on the tributaries. Not so easy.
Just more than 50 percent of our renewable energy comes from hydroelectric power, about seven percent of the country's total electricity needs, an additional incentive to keep some dams in good repair. But we don't inspect them all, we don't repair them all, and it's expensive and sometimes legally problematic to tear them down.
We should at least repair the thousands of dams posing an immediate hazard to people downstream. If we can't do that, or are unwilling to do that, then we should safely remove those dams regardless of the cost.
If we wait, as the operators of the Edenville dam did, it'll be too late; a catastrophic failure is just one intense rain event away. The after-the-disaster costs, which will be considerable, will be our own damned fault.