Image: Conowingo Dam, 16 October 1996, Copyright 1996 by Edward J. Clear/Wikimedia Commons
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Could it happen here? That was the big question in the U.S. in the hours and days after a magnitude 9.0 earthquake and resulting tsunami crippled the Fukushima Daiichi nuclear power plant and destroyed the surrounding region. Most American worries focused on the integrity of our nation's rapidly aging nuclear power plants, many of which are still churning through uranium long past the reactors' original expected lifetimes. Fears were piqued again August 23 when a magnitude 5.8 temblor struck central Virginia, threatening power plants up and down the east coast. But a quieter danger lingers near many of our cities and towns. Tens of thousands of dams, many built before seismic engineering came of age, have the potential to release tsunami-like flash floods in the event of a seismic breach.
In 2009 the American Society of Civil Engineers released a survey of the state of infrastructure in the U.S. The group found that dams are, on average, in terrible disrepair. Of the more than 85,000 dams, more than 4,000 are unsafe or deficient, and nearly 1,800 of those are located where a breach would cause severe damage to life or property. With so many dams, it is hard to know where the gravest danger lies. The average budget for dam inspectors is distressingly low. For instance, Texas employs just seven inspectors to keep an eye on 7,400 dams, and in many states inspectors lack the authority to inspect private dams, including those built to hold back the chemical by-products of mining operations. A report by Switzerland's Paul Scherrer Institute estimates that dams are the most potentially hazardous source of energy. A catastrophe at an average dam has the potential to kill 11,000 people. The second-most-hazardous energy source? Nuclear.
Decades ago, engineers frequently built dams using a slurry of soil and water that would eventually settle into place. Unfortunately, an earthquake might liquefy the core of the dam. Although these dams were most often built in locations that were not thought to suffer from earthquakes (the Lower San Fernando Dam that nearly failed in a 1971 earthquake in the Los Angeles area is a notable exception), our knowledge of just where and when an earthquake may strike is no longer limited to the west coast. "New York City wasn't supposed to be seismic 20 or 30 years ago," says Tarek Abdoun, a civil engineer at Rensselaer Polytechnic Institute, "but the standard for what should require seismic loading has changed." In the past few decades, seismologists have discovered potentially serious fault lines everywhere from the Carolinas to Missouri.
Engineers have begun the process of retrofitting dams that suddenly are found to be located in earthquake-prone areas. But progress is slow and expensive. The Association of State Dam Safety Officials estimates that $50 billion would be needed to repair all the nation's faulty dams. Until that money comes through, fragile nuclear reactors should not be our only worry.
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Reply | Report Abuse | Link to thisA Earthquake was just reported in Peru, 6.8 in the northern country side. The Earthquakes we are seeing recently around the world are mechanical in nature and caused by alignments of planets or Comets like ELEnin. The East coast quake was predicted several weeks ago as large amounts of moisture covered the East weeks earlier. I also predicted the day before the East Coast quake that we would see a rise in the number of quakes in the U.S. and around the world as ELEnin readies to crosses directly in front of Earth on Sept. 9, 2011 at a distance of .223 au.
Reply | Report Abuse | Link to thisSeveral Alignments have already taken place with ELEnin as it entered our solar system and is believed to be the cause of the Japan quake.
The Hurricane Irene that is now barreling down on the east coast could facilitate yet another East Coast Quake. If the amount of rain exceeds 9 inches total a quake of 6.0 or larger could be expected within 10 days. The rebound in the Earth's crust will be accelerated by the moisture and will coincide with stress from ELEnin's crossing.
We will see more quakes, I for one believe the government knows very well that the entire U.S. will have massive quakes through 2012 as planetary alignments are the normal.
In Richmond, it took 45 mins for the local news to notice that the identified epicenter was 5 miles from the North Anna nuclear power station. 45 minutes of "some bricks fell over in Mineral, Bumpass, Cuckoo etc, tremors felt in NYC...". They seemed to have no idea there was a nuclear power station up there. After the locals finally remembered, CNN identified the epicenter as (incorrectly) 20 miles away.
Reply | Report Abuse | Link to thisRonnie, just what are your credentials?
Reply | Report Abuse | Link to thisUsing the science of Astrophotography on images of Fault lines has enabled enhanced visual images that would not have been seen using NASA's 3-D photography. I use a Color Algorithm, with capability photo- study ªORIEº this process uses real-radar electron-resolve color.
Reply | Report Abuse | Link to thisThis is chiefly due to the finite capability of the Photo Imaging instruments which enable unlimited magnification of study subjects.
A recently developed analytical method and process called, ORIE (Optical Remote Image Enhancement), enables visual observation and real time analysis of distance Cosmic Events including Earthly ones, using recorded or raw data (regardless of the source), e.g., photographs, micrographs, radiographs, aperture radar signals, sonograms and electron micrographs, but not limited to only these, better and deeper visual analytical capability along with heretofore absent ability to re solve minute cellular and molecular components and structures while revealing true color, cell component macro/micro structure, spatial relationships, fractal
enhancement amplification and pixel recognition.
The ORIE system identifies structure, elements and compounds contained in the subject of study. Study subjects contained in any photograph, radiograph, aperture radar / Optical processes, - etc. Study subject exploits involving other means of imaging including a image of a Gamma Event, Comets, Planetary bodies and imaging involving e.g.,- x-ray, imaging from microscopes to micrographs from cellular atomic electron imaging levels the ORIE technologies may have in hypothetical, theoretical, experimental exploratory Space
Imaging, and in real time applications have an infinite range of applications in many and varied areas of Astrophysics imaginable research.
ORIE has identified stress ridges and high pressure points of fault lines in thermo images of NASA photos with 6000 DPI.
I am not an expert in this field but my research seems to have produced imagery that provides timely information, if this helps you fine, if not sorry no one can make everyone happy and I certainly am not trying to make everyone happy.
Perhaps instead of "shovel-ready" projects fixing cracked sidewalks, some of the ARRA funds should have gone for studies such as these. To think that the East Coast is not seismically active is foolish. Too many dams and nuclear power plants built on the East Coast have been located with little regard to geologic history. There are plenty of faults, and just because the East Coast isn't sitting on an interface of two plates doesn't mean that earthquakes don't happen here.
Reply | Report Abuse | Link to thisI consider the East Coast the 3rd most dangerous place in the World for a disaster of biblical size in the next 16 months. The Shear number of nuclear power planets in the East and the Crusts Rock formation could create a deadly cocktail producing more damage than previously thought.
Reply | Report Abuse | Link to thisI have said this several times before and it needs to be repeated, the upcoming alignment of planetary bodies in our solar system over the next 16 months could stress plates and rebound areas and cause devastation beyond a humans mind to imagine. The old and unsafe nuclear power planets of the East Coast would suffer greatly in a 7.0 + magnitude quake, you will hear that there is very little chance of this, really?
Irene is going to create massive amounts of rain in the East, will this lead to a Rebound quake in the Earth's Crust that has was compressed during the last Ice age? Time will tell but the older buildings pose a greater likely hood of being damaged even from a smalller quake.
Reply | Report Abuse | Link to thisRECENT STRONG EARTHQUAKES CAUSED BY ALIGNMENTS OF PLANETS AND COMET ELEnin.
Seismicty magnification arises due to Mass Resonance during Earth's long alignments of celestial bodies are producing M6+ quakes.
The cause is related to Tidally triggered resonance magnification mechanism for causality.
During resonance the mantle of the Earth is stressed during astronomical alignments with objects in our solar system and roving bodies transversing it like ELEnin.
In the case of the Washington Earthquake rock compression allowed shaking to be magnified across a large area called mass resonance energy release.
ELEnin, Sun and Uranus had long alignments that maybe considered prime causes for recent mechanical oscillation.
ELEnin seems to have a trajectory different from other Comets, most Comets have inclinations which are outside our solar system and do not align with planets.
It seems relative that ELEnin's speed is nearly 10 times that of other Comets and it's plane of attack is nearly perfectly in line with Earth's orbit.
If you consider everything in the Universe to be mechanical then tidal forces on the Crust would be effected by orbital alignments within the solar system.
Ronald Nussbeck