The private sector will do nothing about this.  They can't.  They have to
make money to survive and the projects are far too expensive for the private
sector to do these projects well.     Old dams don't make money and the
purpose of the private sector is to make money.     Only government can take
of these things, but only if the people have the will to band together and
find a way to tax themselves and do the projects.     There is a purpose for
a private sector but these big jobs are not within that purview.     Neither
is the building of big Research and Development programs like clean energy,
medical technology or the space program.    Did you know that no private
company would ever develop a Nuclear power plant without the government
guaranteeing a 300 million dollar cap on liability?      How much does the
government pay energy companies to keep oil prices low?    Why are we paying
private medical insurance companies to hire management that is incapable of
working with doctors?   How much less would it cost if the government just
did it with everyone being the shareholders like the Green Bay Packers?
We are being taken to the cleaners by socialist countries who are buying our
loans and even our stockmarket.    How long will we sleep peacefully here.
It's 5:30 a.m. and I couldn't sleep.   Is it any wonder?    The private
sector has moved the Cayman Islands.     Now that's patriotism!

REH

 

February 21, 2011


Danger Pent Up Behind Aging Dams


By HENRY FOUNTAIN
<http://topics.nytimes.com/top/reference/timestopics/people/f/henry_fountain
/index.html?inline=nyt-per> 


LAKE ISABELLA, Calif. - Frank Brassell, owner of Nelda's Diner in this town
wedged between the slopes of the southern Sierra Nevada, knows his fate
should Lake Isabella Dam, a mile up the road, suddenly fail when the lake is
full. 

"I work here," Mr. Brassell said, looking around the brightly lighted diner.
"And I live right over there," he added, pointing across the town's main
street. 

"The water would all come down here and it would try to take a right turn
and go under the freeway, and it wouldn't all go," he said. 

"So I'm dead." 

Lake Isabella Dam is just one acute example of a widespread problem: Of the
nation's 85,000 dams, more than 4,400 are considered susceptible to failure,
according to the Association of State Dam Safety Officials
<http://www.damsafety.org/> . But repairing all those dams would cost
billions of dollars, and it is far from clear who would provide all the
money in a recessionary era. 

The stakes are particularly high not just for Mr. Brassell and the other
4,000 residents of Lake Isabella, but for the 340,000 people who live in
Bakersfield, 40 miles down the Kern River Canyon on the edge of California's
vast agricultural heartland. The Army Corps of Engineers
<http://www.usace.army.mil/Pages/default.aspx> , which built and operates
the 57-year-old dam, learned several years ago that it had three serious
problems: it was in danger of eroding internally; water could flow over its
top in the most extreme flood season; and a fault underneath it was not
inactive after all but could produce a strong earthquake. In a worst case, a
catastrophic failure could send as much as 180 billion gallons of water -
along with mud, boulders, trees and other debris, including, presumably, the
ruins of Nelda's Diner - churning down the canyon and into Bakersfield. The
floodwaters would turn the downtown and residential neighborhoods into a
lake up to 30 feet deep and spread to industrial and agricultural areas. 

The potential is for a 21st-century version of the Johnstown Flood
<http://www.jaha.org/FloodMuseum/facts.html> , a calamitous dam failure that
killed more than 2,200 people in western Pennsylvania in 1889. But corps and
local government officials say that the odds of such a disaster are
extremely small, and that they have taken interim steps to reduce the risk,
like preparing evacuation plans and limiting how much water can be stored
behind the dam to less than two-thirds of the maximum. 

Still, they acknowledge that the impact of a dam failure would be enormous.
"It's not just the loss of life, potentially," said David C. Serafini, lead
technical expert for the corps on the project. "It's the economic damages
and the environmental damage, too." 

Corps engineers are preparing to propose fixes later this year. But at best,
repairs would not begin until 2014 and could cost $500 million or more,
money that would have to be approved by Congress. 

Nationwide, the potential repair costs are staggering. A 2009 report by the
state dam safety officials' group put the cost of fixing the most critical
dams - where failure could cause loss of life - at $16 billion over 12
years, with the total cost of rehabilitating all dams at $51 billion. But
those figures do not include Lake Isabella and other dams among the
approximately 3,000 that are owned by the federal government. The corps, for
example, says that more than 300 of the roughly 700 dams it is responsible
for need safety-related repairs, and estimates the total fix-up bill at
about $20 billion. 

The corps has already spent about $24 million just to determine the scope of
the problems at Lake Isabella, and with the New Orleans levee
<http://topics.nytimes.com/top/news/science/topics/dams_and_dikes/index.html
?inline=nyt-classifier>  failures during Hurricane Katrina
<http://topics.nytimes.com/top/reference/timestopics/subjects/h/hurricane_ka
trina/index.html?inline=nyt-classifier>  a lingering memory, Congress has
appropriated money for other federal dam repair projects as well. 

But about two-thirds of all dams are private, and financially struggling
state and local governments own most of the remainder. It is difficult to
predict how needed repairs to these dams will be financed; legislation to
provide federal money to help has languished in Congress. What's more, the
number of high-risk dams keeps rising as structures age, downstream
development increases and more accurate information is obtained about
watersheds and earthquake hazards. 

Among the corps's dams, Lake Isabella is one of 12 that are ranked in the
highest category, as a dam with serious problems and serious failure
consequences, given the large downstream population. "The classification is
it's an unsafe dam," said Eric C. Halpin, the corps's special assistant for
dam and levee safety. But Mr. Halpin noted that 319 of the corps's dams were
considered "actionable from a safety standpoint." 

Lake Isabella would be one of the more expensive projects, but then again,
its problems are legion. It is actually two earthen dams, a main one that is
185 feet high and an auxiliary one that sits on higher ground and is 100
feet high. With a rock ridge between them, they stretch for about a mile
across the Kern River Valley. 

For six decades the dams have controlled flooding on the Kern, helping
Bakersfield to grow and thrive. And the lake that formed behind the dam has
become the main driver of the economy of Lake Isabella and other towns,
bringing fishers, boaters and whitewater rafters to the area. 

But there have always been people in the area who felt the dams were flawed.


David Laughing Horse Robinson, an artist and teacher who lives in the
lakeside town of Kernville, said his grandfather, who worked on the dam, and
others used to talk about it. "Constantly," he said. "How it was the
stupidest thing they ever did. It's doomed." 

Water seeps through the Lake Isabella dams, as it does through most earthen
dams, which account for a vast majority of dams in the United States. But
the seepage at Lake Isabella was especially severe - it is what prompted the
corps to perform a full-scale study of the dam. 

Water seeping through a dam can erode it from the inside out, to the point
where the dam may fail. Engineers have learned to build structures into dams
like drains and filters, to stop erosion and allow infiltrating water to
drain safely away. But the Lake Isabella dams were constructed before such
features became commonplace. 

"It was built with the best available knowledge and technology at the time,"
said Veronica V. Petrovsky, who is managing the project for the corps. 

That knowledge, or lack of it, extended to the understanding of the large
and complex watershed, which includes the slopes of Mount Whitney, the
tallest peak in the contiguous United States. To determine how big the
spillway needs to be, it is critical to know how much water might be
impounded behind the dam each year. 

Calculations show that in an extreme year with a "probable maximum flood,"
the spillway would be far too small. "We could not release the water fast
enough," Ms. Petrovsky said. "It would overtop." An overtopped dam can fail
quickly as the water erodes the downstream side. 

Concerns about seepage, in particular, prompted the corps to restrict the
lake level, because less water creates less hydrostatic pressure that would
force water through the dam. Earlier this winter, the lake was so low that
water did not even lap up against the auxiliary dam. But the corps has been
monitoring the heavy rains and snowfall that California has experienced this
winter and says that in the spring and summer it may be necessary to divert
water through the spillway to maintain the safer lake level. Overtopping,
however, presents only a "small concern," the corps said. 

With both seepage and overtopping there would be plenty of warning that the
dam was in jeopardy, allowing Lake Isabella and Bakersfield residents to
evacuate. An earthquake would be a more immediate disaster, although
Bakersfield would still have about seven hours before a wall of water made
its way down the canyon, according to the corps. 

The auxiliary dam was built, knowingly, on the Kern Canyon fault, one of
many in the region. At the time the corps brought in seismologists and
geologists who concluded that the fault was not active. 

Only recently have scientists been able to accurately detect and measure
ancient earthquakes, a field known as paleoseismology. Mr. Serafini and
others determined that there have been three significant earthquakes on the
fault in the past 10,000 years. "We have got a fairly active fault on our
hands," Mr. Serafini said. The last quake occurred about 3,400 years ago, he
added. 

It's possible to construct a safe earthen dam on an active earthquake fault,
by using the proper materials to minimize settlement or slumping when
shaken, and including drains and filters to help stop the inevitable cracks
from growing through erosion. Not only do the Lake Isabella dams lack those
features, but the auxiliary dam was built on sediments that could turn into
a virtual liquid in a quake, leading to even greater damage. 

While Mr. Serafini and his team are still working on proposals, the
likeliest solutions include blasting a much bigger spillway out of bedrock
adjacent to the main dam and using the excavated rock to build a buttress -
essentially an entirely new dam - downstream from the auxiliary dam. The old
dam could still move in an earthquake, Mr. Serafini said, but the buttress
would have the necessary drains and filters to prevent failure. 

While the proposals are being fleshed out, the corps team has been holding
meetings in the area to let people know what the possibilities are. 

"We don't hear much from the people of Bakersfield," Ms. Petrovsky said.
"It's one of those 'out of sight, out of mind' things. You forget there's a
dam up here holding back a lot of water." 

Not so in Lake Isabella, however, where the dam, and its potential for
failure, are harder to ignore. 

"I think we've all put some thought into it," said Mr. Brassell, the diner
owner. "But anytime you have a diverse group of people there are going to be
those who are panicked at some level, and those who are calm. Faith in God,
you know. He's going to do what he wants." 

 

 

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