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Engineers up failure risk for dam protecting Disneyland, dozens of Orange County cities
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Leroy N. Soetoro
May 22, 2019, 12:30:20 PM5/22/19
to
https://www.latimes.com/local/lanow/la-me-ln-prado-dam-flood-risk-failure-
20190516-story.html
Federal engineers are raising alarms that a “significant flood event”
could compromise the spillway of Southern California’s aging Prado Dam and
potentially inundate dozens of Orange County communities from Disneyland
to Newport Beach.
After conducting an assessment of the 78-year-old structure earlier this
month, the U.S. Army Corps of Engineers announced that it was raising the
dam’s risk category from “moderate” to “high urgency.”
“Our concern right now is about the concrete slab of the spillway and how
well it will perform if water were to spill over the top of the dam,” said
Lillian Doherty, the Army Corps’ division chief. “We will determine
whether or not it is as reliable as it should be.”
(Los Angeles Times)
Located beside the 91 Freeway on the border of Riverside and Orange
counties, the dam impounds little to no water for much of the year. During
periods of heavy rain, however, the structure is intended to collect water
and prevent flooding along the Santa Ana River.
Doherty said her agency is working with a national team of experts to
develop interim and permanent risk-reduction measures at the dam, as well
as public outreach strategies to alert the estimated 1.4 million people
who live and work in 29 communities downstream.
The sudden downgrade in the structure’s evaluation comes after major
problems have been identified in California dams.
In February 2017, a concrete spillway at the Oroville Dam disintegrated
during heavy rains and triggered the evacuation of more than 180,000
people. The head of the California Water Resources Department, which
operates the dam, was removed after an independent probe found the failure
was the result of a lax safety culture.
That same year, the Corps of Engineers discovered that the 60-year-old
Whittier Narrows Dam, about 40 miles to the west of Prado Dam, was
structurally unsafe and posed a potentially catastrophic risk to more than
1 million people in working-class communities along the San Gabriel River
floodplain.
In that case, engineers found that intense storms could trigger a
premature opening of that dam’s massive spillway, swamping homes, schools,
factories and roads from Pico Rivera to Long Beach. Engineers also found
that the earthen structure could fail if water were to flow over its
crest.
The Corps estimates it will cost roughly $600 million in federal funds to
upgrade the Whittier Narrows facility, which has been reclassified as the
agency’s highest priority nationally because of the risk of “very
significant loss of life and economic impacts.”
Now, given concerns that Prado Dam poses a flood threat to much of Orange
County, the agency is collaborating with Los Angeles, Orange and Riverside
counties and several dozen municipalities to develop emergency plans that
could be implemented before repairs to the dams are completed.
Col. Aaron Barta said the retrofit operations on the spillways at both
dams could begin as early as 2021.
An $880-million effort to increase storage capacity for floodwaters and
sediment at Prado Dam has been underway since 2002. It includes raising
the spillway crest by 20 feet to an elevation of 563 feet, replacing
outlet systems, increasing the reservoir area, building new dikes and
improving the wetlands behind the dam and the downstream channel for flood
control purposes, as well as for habitat and possible recreational
opportunities.
Despite a development boom in neighboring Chino, Corona, Norco and
Eastvale, the 2,150 acres of wetlands behind the dam comprise a labyrinth
of channels, ponds and forests that are havens for threatened and
federally endangered species including red-sided garter snakes and least
Bell’s vireos.
In the meantime, the Prado and Whittier Narrows dams continue to be fully
functional and operable during storm events, said Dena O’Dell, a
spokeswoman for the agency.
“Corps staff is routinely on site at Prado Dam to operate and monitor the
dam during rain events,” she said. “The Corps’ assessment of the dam
doesn’t mean that failure is taking place; it means the agency has
identified performance concerns that require attention to meet the corps’
rigorous dam safety standards.”
But some researchers doubt the overall safety of aging federal flood
control systems that were not designed with climate change in mind.
They argue that in a warming world, regions such as California will
experience more whiplashing shifts between extremely dry and wet periods.
These cycles, they say, will seriously challenge California’s ability to
control flooding, as well as store and transport water.
“A troubling theme is emerging as the Corps reviews its portfolio of large
flood control systems that were built a long time ago and are now showing
signs of severe stress,” said Daniel Swain, a UCLA climate scientist.
“Federal engineers are finding that these systems are not as resilient as
they thought they were, and that the frequency of what were regarded as
once-in-a-lifetime storms is increasing significantly.”
Doherty would not go that far.
“Unpredictable things can happen,” Doherty said. “But we are the
preeminent flood risk management and engineering agency in the United
States — we are all about keeping people safe.”
--
No collusion - Special Counsel Robert Swan Mueller III, March 2019.
Donald J. Trump, 304 electoral votes to 227, defeated compulsive liar in
denial Hillary Rodham Clinton on December 19th, 2016. The clown car
parade of the democrat party ran out of gas and got run over by a Trump
truck.
Congratulations President Trump. Thank you for cleaning up the disaster
of the Obama presidency.
The Obama-led Committee on Foreign Investment in the United States (CFIUS)
approved Uranium One in fall 2010. With a little luck, we'll see
compulsive liar Hillary Clinton in jail before she dies.
Under Barack Obama's leadership, the United States of America became the
The World According To Garp.
Obama increased total debt from $10 trillion to $20 trillion in the eight
years he was in office, and sold out heterosexuals for Hollywood queer
liberal democrat donors.
20190516-story.html
Federal engineers are raising alarms that a “significant flood event”
could compromise the spillway of Southern California’s aging Prado Dam and
potentially inundate dozens of Orange County communities from Disneyland
to Newport Beach.
After conducting an assessment of the 78-year-old structure earlier this
month, the U.S. Army Corps of Engineers announced that it was raising the
dam’s risk category from “moderate” to “high urgency.”
“Our concern right now is about the concrete slab of the spillway and how
well it will perform if water were to spill over the top of the dam,” said
Lillian Doherty, the Army Corps’ division chief. “We will determine
whether or not it is as reliable as it should be.”
(Los Angeles Times)
Located beside the 91 Freeway on the border of Riverside and Orange
counties, the dam impounds little to no water for much of the year. During
periods of heavy rain, however, the structure is intended to collect water
and prevent flooding along the Santa Ana River.
Doherty said her agency is working with a national team of experts to
develop interim and permanent risk-reduction measures at the dam, as well
as public outreach strategies to alert the estimated 1.4 million people
who live and work in 29 communities downstream.
The sudden downgrade in the structure’s evaluation comes after major
problems have been identified in California dams.
In February 2017, a concrete spillway at the Oroville Dam disintegrated
during heavy rains and triggered the evacuation of more than 180,000
people. The head of the California Water Resources Department, which
operates the dam, was removed after an independent probe found the failure
was the result of a lax safety culture.
That same year, the Corps of Engineers discovered that the 60-year-old
Whittier Narrows Dam, about 40 miles to the west of Prado Dam, was
structurally unsafe and posed a potentially catastrophic risk to more than
1 million people in working-class communities along the San Gabriel River
floodplain.
In that case, engineers found that intense storms could trigger a
premature opening of that dam’s massive spillway, swamping homes, schools,
factories and roads from Pico Rivera to Long Beach. Engineers also found
that the earthen structure could fail if water were to flow over its
crest.
The Corps estimates it will cost roughly $600 million in federal funds to
upgrade the Whittier Narrows facility, which has been reclassified as the
agency’s highest priority nationally because of the risk of “very
significant loss of life and economic impacts.”
Now, given concerns that Prado Dam poses a flood threat to much of Orange
County, the agency is collaborating with Los Angeles, Orange and Riverside
counties and several dozen municipalities to develop emergency plans that
could be implemented before repairs to the dams are completed.
Col. Aaron Barta said the retrofit operations on the spillways at both
dams could begin as early as 2021.
An $880-million effort to increase storage capacity for floodwaters and
sediment at Prado Dam has been underway since 2002. It includes raising
the spillway crest by 20 feet to an elevation of 563 feet, replacing
outlet systems, increasing the reservoir area, building new dikes and
improving the wetlands behind the dam and the downstream channel for flood
control purposes, as well as for habitat and possible recreational
opportunities.
Despite a development boom in neighboring Chino, Corona, Norco and
Eastvale, the 2,150 acres of wetlands behind the dam comprise a labyrinth
of channels, ponds and forests that are havens for threatened and
federally endangered species including red-sided garter snakes and least
Bell’s vireos.
In the meantime, the Prado and Whittier Narrows dams continue to be fully
functional and operable during storm events, said Dena O’Dell, a
spokeswoman for the agency.
“Corps staff is routinely on site at Prado Dam to operate and monitor the
dam during rain events,” she said. “The Corps’ assessment of the dam
doesn’t mean that failure is taking place; it means the agency has
identified performance concerns that require attention to meet the corps’
rigorous dam safety standards.”
But some researchers doubt the overall safety of aging federal flood
control systems that were not designed with climate change in mind.
They argue that in a warming world, regions such as California will
experience more whiplashing shifts between extremely dry and wet periods.
These cycles, they say, will seriously challenge California’s ability to
control flooding, as well as store and transport water.
“A troubling theme is emerging as the Corps reviews its portfolio of large
flood control systems that were built a long time ago and are now showing
signs of severe stress,” said Daniel Swain, a UCLA climate scientist.
“Federal engineers are finding that these systems are not as resilient as
they thought they were, and that the frequency of what were regarded as
once-in-a-lifetime storms is increasing significantly.”
Doherty would not go that far.
“Unpredictable things can happen,” Doherty said. “But we are the
preeminent flood risk management and engineering agency in the United
States — we are all about keeping people safe.”
--
No collusion - Special Counsel Robert Swan Mueller III, March 2019.
Donald J. Trump, 304 electoral votes to 227, defeated compulsive liar in
denial Hillary Rodham Clinton on December 19th, 2016. The clown car
parade of the democrat party ran out of gas and got run over by a Trump
truck.
Congratulations President Trump. Thank you for cleaning up the disaster
of the Obama presidency.
The Obama-led Committee on Foreign Investment in the United States (CFIUS)
approved Uranium One in fall 2010. With a little luck, we'll see
compulsive liar Hillary Clinton in jail before she dies.
Under Barack Obama's leadership, the United States of America became the
The World According To Garp.
Obama increased total debt from $10 trillion to $20 trillion in the eight
years he was in office, and sold out heterosexuals for Hollywood queer
liberal democrat donors.
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