Climate change creates new flooding risks for U.S. nuclear reactors safety

Extreme weather disasters, especially floods, are on the rise (see Two seminal Nature papers join growing body of evidence that human emissions fuel extreme weather, flooding).  Last year, we had Tennessee’s 1000-year deluge aka Nashville’s ‘Katrina’.  And  Coastal North Carolina’s suffered its second 500-year rainfall in 11 years.

Craig Fugate, who heads the U.S. Federal Emergency Management Agency, said in December, “The term ‘100-year event’ really lost its meaning this year” (see Munich Re: “The only plausible explanation for the rise in weather-related catastrophes is climate change”).

A couple weeks ago, I asked how many U.S. nuclear plants are vulnerable to a tsunami and/or a 500-year 100-year flood? Here a very initial treatment of the flood vulnerability issue.

The following article by Sean Pool, Elaine Sedenberg and Matt Woelfel is cross-posted at Science Progress.

As the situation at Japan’s damaged Fukushima Daiichi nuclear facility continues to worsen,  policymakers in the United States are taking the opportunity to review the safety policies for our aging nuclear reactors.

Japan’s recent 9.0 magnitude earthquake and the tsunami it caused together killed 9,737 people and left an additional 16,501 missing. The destruction left millions homeless and caused almost $200 billion in damage.

These natural disasters caused severe damaged to 4 of the 6 reactors at the Fukushima Daiichi nuclear plant, leaving them without functioning primary, secondary, or tertiary cooling systems. The resulting partial meltdown of the core at one reactor and of a waste fuel rod storage tank in another has resulted in the release of radioactive material into the atmosphere, soil, and water, forcing the evacuation of what was at first a 12-mile radius and now a 19-mile radius surrounding the facility.

Though reactors in the United States are built to strict safety standards, they are nevertheless vulnerable to any number of natural and manmade disasters, from earthquakes and tsunamis to flash floods, droughts, and hurricanes. U.S. reactor safety standards have been effective in preventing catastrophe, though a recent report highlights 14 “near misses” where improperly implemented safety protocols nearly caused major problems. More troublingly, many of these standards were based on an understanding of our climate system that is now 40 years out of date. Today we know that climate change is making floods, droughts, and hurricanes stronger and more frequent, which means we must ask whether our safety standards, even when followed perfectly, are enough to prevent disaster.

As the Nuclear Regulatory Commission conducts its review of U.S. nuclear safety in the wake of the Fukushima meltdown, they need to be sure they are doing a thorough review of all possible risks, and should not ignore recent science about how climate change could increase those risks.

Current state of US nuclear plant safety

The United States currently has 104 functioning power reactors at 65 sites around the country, roughly a quarter of which use the same “Mark 1” containment vessel design used in the failing Japanese reactors. They supply roughly 20 percent of the country’s total electricity needs. Nuclear plants demand large sources of water in order to cool and control the core temperatures of the reactors that power them. To meet this inevitable requirement, nuclear plants are situated in low-lying areas near rivers and lakes, and many others are built on the coasts. This proximity leaves these plants vulnerable to floods and other water-related disasters.  (See our map below.)

(click for a high res version.)

Many regulations are already in place to ensure that nuclear energy remains safe from floods, surges, tsunamis, and droughts. The Nuclear Regulatory Commission, or NRC, oversees licensing applications, reactor specifications, and radioactive waste disposal. The Advisory Committee on Reactor Safeguards, or ACRS, also reviews the adequacy of proposed safety standards and creates individualized specifications to withstand the projected worst-case disasters for each plant location. Nuclear facilities are initially granted a 40-year license that must be renewed after 20 years. They then have the opportunity to extend their license for additional 20-year increments.

The problem is that our nuclear reactors are all old. Thirty years old on average in fact, since political will for new nuclear reactors has weakened since the 1979 Three Mile Island incident. Seven operating reactors have eclipsed their original 40 year lifespans and been permitted to operate for another 20 years. This makes them vulnerable to problems, like stronger floods caused by climate change, about which we had considerably less knowledge three to four decades ago when the plants were built.

Climate change will increase certain risks

Climate change will compound existing weather-related risks. In the years since most of our nuclear reactors were built, we’ve learned that climate change is increasing the risk profile of many kinds of extreme weather. Two scientific studies published this year in Nature have supported this. Large and destructive floods once thought likely to happen only once in 100 years on average are now expected to happen every 20 years: a five-fold increase. Similar trends hold for droughts, hurricanes, and wildfires. Droughts and heat waves can impact nuclear reactors because they use large amounts of water in the power generation process. If water levels drop too low, or the temperature of adjacent water bodies rises too high, the ability of the reactors to operate can be impaired. Sea-level rise is also of particular concern, since many of our nuclear facilities are located on the coast.

In response to this growing awareness of disasters that can result from climate change, the International Atomic Energy Agency, or IAEA, released a safety guide in 2003 detailing flood-related hazards to nuclear power plants on coastal and river sites. The safety guide suggests that newly constructed plants should account for several consequences of climate change over the lifespan of the plant:

  • Rise in mean sea level: 35-85 cm
  • Rise in air temperature: 1.5-5 °C
  • Rise in sea or river temperature: 3 °C
  • Increase in wind strength: 5-10 percent
  • Increase in precipitation: 5-10 percent

Higher sea levels, in combination with the warmer air, water, and sea temperatures will produce larger, stronger waves, increase the flow rate of rivers, and alter the dominant wind patterns, according to the report. The IAEA recommendations offer a good framework for assessing siting of new nuclear facilities, but current safety standards at the 104 operating nuclear reactors in the United States remain in question. Are they sufficient to deal with the increased risks caused by climate change?

This is a question we must answer, and soon. As we have written at Science Progress before, climate change creates considerable uncertainty for businesses and governments who must make difficult decisions that will affect the way we do business over the next 10, 20, or 40 years. In making long-term decisions about policy and business, decision makers need to have all the data they can get. The problem is that extremely rare events by definition provide us with little opportunity for study, even though their impacts can be catastrophic.

The seawalls at the Fukushima Daiichi reactor complex, for example, were designed to withstand an 18-foot wave, though the tsunami that caused the eventual nuclear meltdown was estimated to have been more than 40 feet high. Japanese engineers simply didn’t have enough data to accurately predict just how big a tsunami could be. Could this happen in the United States? For reference, the San Onofre reactor in California is built right on Pacific coast, with a sea wall of only 23 feet.

The bottom line is that sometimes, what we think to be a “worst case” scenario is not really the worst case. Just because there is uncertainty about how climate and weather will affect our nuclear reactors does not mean we should ignore the issue. Quite the opposite; it would be negligent to ignore this uncertainty as we continue to assess our nation’s nuclear safety standards.

The Nuclear Regulatory Commission has taken some steps to incorporate current climate science into its standards, but it has not gone far enough. In 2009, the NRC released an information notice that suggested plants re-evaluate flood protection measures, but they did not require action. To make matters worse, the guidelines in use were established in 1977, with the latest updates occurring in 1984. As the Nuclear Regulatory Commission conducts its review of U.S. nuclear safety in the wake of the Fukushima meltdown, they need to be sure they are doing a thorough assessment of all possible risks, and should not ignore recent science about how climate change could increase those risks.

Countries around the world have already begun to take increased risks from climate change into account in their nuclear safety protocols.  It’s high time the United States follows suit. The United Kingdom has insisted that new nuclear plants demonstrate countermeasures taken to prevent damage from more extreme floods, France has begun reviewing all 58 of its reactors to check how much flooding they can handle, and Austria has even called for nuclear “stress tests” similar to those banks undergo. Germany has even ordered all reactors built prior to 1980 (all American reactors would qualify) to be shut down for three months.

The disaster in Japan has afforded the United States the opportunity to re-examine the safety of its own fleet of nuclear reactors. Given how often we underestimate the “worst-case” scenario, this is an opportunity we cannot afford to miss.

— Sean Pool is Assistant Editor for Science Progress, Elaine Sedenberg is an Intern with Science Progress, and Matt Woelfel is an Intern with CAP’s Energy Opportunity team. The authors would like to thank Kate Gordon, Richard Caperton, and Valeri Vasquez, and Evan Hansleigh for their invaluable contributions to the article.

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19 Responses to Climate change creates new flooding risks for U.S. nuclear reactors safety

  1. Prokaryotes says:

    Climate change also means = increase in geomorphological response.

  2. Mark says:

    We saw in a post a few days ago how a Japanese seismologist warned in 2009 about tsunami risks at Japan’s plants, and called for more research. Back in 1861 ten FEET of rain fell in California in 45 days. It was called “Arkstorm” and a 2010 USGS study tried to predict the impact should it repeat, which the geologic record tell us it will every 150-200 years if the pattern holds. The answer? One trillion dollars (damage combined with economic losses in a later study). BUT and here’s the kicker…….

    The reports ignored California’s nuclear plants! Instead they assumed the plants would quietly shut down, and survive the event in pristine condition. releases/ 2011/ 01/ 110117142512.htm releases/ 2011/ 03/ 110307142236.htm

    Original USGS report
    (click the link on the right to see the full report)

    From pg 42

    “Damage to power system components from landslides is not accounted for, nor is any special consideration made of shutdown of nuclear power plants or of other generating facilities not in the flooded areas…. These limitations argue for a more thorough assessment by PG&E and other utilities.”

    It’s hard to imagine what landslides or the floods from 10 feet of rain could do to these plants, unless there is a followup study. Its hard to imagine how that will be paid for, unless the GOP decides to continue funding USGS NOAA and NASA to think about these things.

  3. Colorado Bob says:

    JR –
    On the flip side the Browns Ferry reactors have had to shut down twice since 2007 because the water discharges would increase the temperature of the Tenn. River during heat waves.

  4. Colorado Bob says:

    New Zealanders have been issued with a stark warning to expect “surprises” by scientists who say they cannot keep up with extreme weather events linked to climate change.

    Scientists opened a climate change conference in Wellington yesterday by stating that changes in climate being experienced around the globe were beyond their worst-case scenarios.

  5. Mulga Mumblebrain says:

    I suppose you have not seen the latest outbreak of mass idiocy in Australia. The unfortunate Tim Flannery, who is despised and reviled by the Right here, the Murdoch apparat in particular (because he is intelligent and honest, two traits they never possessed, and resent)was on radio with Andrew Bolt, a local version of Rush Limbaugh, but with less charm. He was attempting to explain to the rabble of Bolt’s ‘audience’ that cutting greenhouse emissions was pretty urgent. Then he mentioned the fact that CO2 would remain in the atmosphere for up to a thousand years, so it was vital not to pump any more into the atmosphere now.

    [JR: I saw it and emailed Flannery and will run his correction soon. Meant to do it sooner.]

    Of course it is always dangerous talking sense to imbeciles. It doesn’t impress the Dunning Krugerites, who resent those more intelligent than themselves. And thus it transpired. The Right, from Tony (Climate change is crap) Abbott, the Leader of the Opposition down, ‘seized on’ or ‘leapt on’ (two nauseating expressions that are de rigeur amongst our journalistic reptiles) this observation. The resulting outpouring of cretinism was a joy to behold, as one idiot, high and low, after another paraded their stupidity, or worse. Apparently current climate change was caused by emissions in the 11th century, so let’s start blaming Harold of England and William the Conqueror. And Flannery was saying that nothing we do now will have any effect for a thousand years, so why bother? They had a jolly time, growing quite hysterical, and delighting in their own great intellect, but it’s died down a bit now. A pity, as I do enjoy a ‘moronic panic’ when fanned into life by the MSM, but you can bet your bottom dollar that it will be back.

    To top it all and illustrate the self-destructive nature of our ‘adversarial politics’ and ‘demon-crazy’, the new Premier of New South Wales. Barry O’Farrell, a Rightwinger who has practised the new politics of dissembling by posing as a ‘moderate’ over the last few years, declared that he would ‘take the fight up’ to the Commonwealth Government over the carbon tax that was widely credited with worsening the debacle for Labor in NSW. Apparently we display our ineffable superiority to ‘dictatorships’ like China (the subject of an increasingly vicious wave of hatemongering in the MSM)by squabbling like children, seeking advantage, sabotaging the other side and refusing co-operation with the other side of politics (and society)even in the face of a growing threat to the survival of our species. If it wasn’t so tragic, the arrogance and self-delusion would be truly laughable.

  6. Davos says:

    Looks like Yucca Mountain is nice and centrally located to handle all the spent fuel rods :)

    Perhaps a mountain in WV should do instead…I suppose there are some left.

  7. paulm says:

    #5 Mulga, very nice piece!

  8. paulm says:

    Getting closer to home….

    Radiation In Milk: Low Levels Found In Milk From West Coast

    A reminder of nuclear legacy…
    Chernobyl ‘still causing cancer in British children’, 23 April 2006

    Official measurements – published in a report launched in London yesterday – show that at least 34 per cent of the country will remain radioactive for centuries as the result of the accident, which took place 20 years ago on Wednesday.

    The report says the radioactive caesium – and the doses of radiation it gives Britons – will only “decline slowly over the next few hundred years”.

    Scientists at Newcastle University examined rates of thyroid cancer in children across northern England before and after the Chernobyl cloud passed overhead.

    They found slight increases across the region – and an abrupt 12-fold jump in Cumbria, which received most fall-out. Professor Louise Palmer, who led the study, said yesterday that the results were “consistent with a causal association with the Chernobyl accident”.

  9. paulm says:

    Chernobyl nuclear accident: figures for deaths and cancers still in dispute
    • Suspected infant mortality rise difficult to prove
    • Predicted deaths range from 4,000 to half a million

  10. Prokaryotes says:

    7 hurt as tornadoes, storms batter central Fla.

    Windy, rainy weather furiously swept through central Florida Thursday, knocking out power to tens of thousands of people, flooding roads and toppling trucks and small planes.

    By 2 p.m., about 88,000 Tampa Electric Company customers were without power. Downed power lines were spotted in several counties and in the city of Tampa.

    Wind gusts of up to 90 mph were felt in Tampa, and emergency crews were responding to a report of a commercial building collapse with no injuries.

    A janitor at an elementary school in a suburb northwest of downtown Tampa was taken to a hospital after he was nearly struck by lightning.

    A few small planes had flipped over at the St. Petersburg-Clearwater Airport. Large traffic jams happened on a bridge when a tractor-trailer truck flipped onto two cars — people in all the vehicles refused medical treatment.

    There have been multiple reports of small tornadoes across the region. Wind gusts of up to 70 miles per hour were reported in St. Petersburg, where skies turned dark around 11:15 a.m.

    In Tarpon Springs on the Gulf, officials were handing out sand bags because of fears about flooding at high tide.

  11. paulm says:

    Just amazing… local government rushing around trying to adapt to Climate Broiling and federal GOP totally not accepting the science or their responsibility to do anything about it.

    What a farcical state of affairs.

  12. Mulga Mumblebrain says:

    God, Davos #6, what a brilliant idea! Have you contacted the Kochtopus yet? Make sure to patent your idea first, or they might gazump you.

  13. paulm says:

    What a price to pay…Japan 100yrs of nuclear misery!

  14. Dr.A.Jagadeesh says:

    Excellent analysis on Nuclear Reactors in US and their safety.

    Dr.A.Jagadeesh Nellore(AP),India

  15. David B. Benson says:

    While the existing nuclear reactors cannot be moved, new ones need not be located in even 500 year flood plains. Some few coal burning thermal plants use air cooling and so could nuclear powered thermal generators. Converting existing thermal plants to use either water or air cooling towers would offer an additional layer of protection from flooding and alos from river over-temperature conditions.

  16. joyce says:

    I just read this by Busby “Deconstruction Nuclear Experts”:

    It is tragic what we are not being told. I have been watching the MSN in amazement as “experts” tell us not to worry–that it’s not that bad…

  17. phil says:

    The USA facilities must be so hardened from a terrorist attack that absolutely no one mentions it when proclaiming your Homer Simpson power source immune from disasters.
    Isn’t entombing the reactor sites in concrete an unnecessary complication? You’d have to cut up the concrete to remove it later anyway. It will leach caesium 137 into the ocean for millenia and eventually be dug up anyway. Isn’t it better to construct a purposefully built facility away from storm surges and tsunami? There is remote controlled construction machinery that could lift a city’s worth of mass to a more secure nearby location. I envision putting a few hundred rail cars full of water in some sort of tomb, all with venting apparatus and changeable adsrob/absorb solids in the same airspace. The watertomb solids and reactor site soil/concrete/trees/debris could be placed in a lesser dry storage. Both north of Tokyo’s aquifer and inland of the ocean. You’d want to minimize the mass at Daichi; seems like a horrible long-term storage site.

  18. Interesting post. I had not thought much about extreme flood events and nuclear plants. At Climate Central, we recently published an article on sea level rise and nuclear plants, noting the direct hit on the Turkey Point facility from Hurricane Andrew in 1992.

    I’m curious to see whether the NRC incorporates sea level rise and other climate-related risks into its re-assessments of plant safety in the wake of Fukushima.

  19. Solar Jim says:

    My comment may be awaiting moderation at number four, however you will not receive moderation from me. I’m afraid I’ve had a bit of a meltdown. I’ve gone radioactive and am thinking about becoming radio-active, perhaps on a public station. I’m sick of nuclear power, and soon a whole lot more will be too. And gee or ge, it sure is swell to have the pres. jobs and competition man of the corporate citizen which pays no taxes and gets a credit, gets taxpayer bailouts and wants to promote the nuke scam, represent us little sap sucker, shoe leather, glue holders for the looting of the national trust. They bring imagination to strife.