A series of storms fueled by a mild El Nino hit southern California during the week of 17 – 23 January, 2010.  Rain, which was heavy at times, turned canyons that were burned during the recent Station fire into raging torrents of mud and debris.  Mandatory evacuation orders were issued by law enforcement for over two-thousand residents living in the foothills below where the Station fire occurred.  Fortunately, much of the mud and debris that rushed through the upper canyons did not make it to the foothill communities thanks to properly functioning empty debris basins located at the mouths of the canyons.  The debris basins stopped an immense volume of material that ranged from boulders and burned trees to gravel and mud, filling some to capacity before the storms ended.  If the duration of the storms was longer or the intensity of rain that fell on Thursday or Friday been equal to that which fell earlier in the week, the situation could have been much worse; debris flows and mud would have inundated the communities below.

The following photos document the Mullally debris basin and its inlet filling to capacity over the duration of the storms:

For best viewing, open each photo in a separate browser tab and toggle back and forth between them.

Mullally DB - Photo by Robert Leeper, USGS 01/14/10

Mullally DB - Photo by Robert Leeper, USGS 01/20/10

Mullally DB - Photo by Robert Leeper, USGS 01/22/10

Mullally DB Inlet - Photo by Robert Leeper, USGS 01/14/10

Mullally DB Inlet - Photo by Robert Leeper, USGS 01/20/10

Mullally DB Inlet - Photo by Robert Leeper, USGS 01/22/10

The Multi-Hazards Demonstration Project is coordinating the USGS response to the recent Station fire in southern California.  This response includes ash sampling, debris flow monitoring and warning, and the impact on species in the burn area.  As a part of the debris flow monitoring project, we recorded the geomorphic response of several watersheds within the burn area to the storm that occurred 12 – 14 December, 2009.  Responses ranged from minor erosion to hazardous flash flooding and debris-flow.  The following photos document changes in a stream channel that occurred as a result of a debris flow produced during the afternoon of 13 December, 2009.  The photos were collected by Robert Leeper while conducting fieldwork with Jason Kean on 8 December, 2009 and 15 December, 2009.  The debris flow study area was selected by Jason Kean and Dennis Staley.

Mouth of side canyon in Big Tujunga 12/08/09

Mouth of side canyon in Big Tujunga 12/15/09

Farther up from mouth of side canyon in Big Tujunga 12/08/09

Farther up from mouth of side canyon in Big Tujunga 12/15/09

]]> http://urbanearth.gps.caltech.edu/2010/01/05/station-fire-fieldwork/feed/ 0 http://urbanearth.gps.caltech.edu/2009/10/18/foiling-waters-fury/ http://urbanearth.gps.caltech.edu/2009/10/18/foiling-waters-fury/#comments Sun, 18 Oct 2009 18:32:28 +0000 admin http://urbanearth.gps.caltech.edu/?p=764 By Janet Zimmerman

” The potential for devastating floods have not garnered the same attention or concern as earthquakes among planners and the public, said Dale Cox, project manager for the U.S. Geological Survey’s Multi-Hazards Demonstration Project, the group behind the drills.”

“The Big One as it relates to a storm is not really there for people. They’re not thinking of 1861 — probably not even of 1986 — and it’s not your water-cooler disaster that you might talk about. In a sense, that’s a problem … these extreme events are, given climate change, more likely in the future.”

Read more:
http://www.pe.com/localnews/inland/stories/PE_News_Local_S_ark11.43eb34a.html

“Had the storm hit farther south, it could have caused devastating mudslides on recently burned Southern California mountain slopes. Had it occurred later in winter, when the ground was saturated, the storm might have caused dangerous floods.”

“”We just dodged a bullet,” said Lucy Jones, chief scientist at the U.S. Geological Survey Multi-Hazards Demonstration Project, which is researching atmospheric rivers.”

Read more:
http://www.modbee.com/local/story/896754.html#ixzz0bCBckJVi

Note: The story also appeared on the front page of the Sacramento Bee.

As people in northern California begin to assess damage from the high winds and heavy rain of October 13 and 14, they may wonder what hit them. The answer, according to Dave Reynolds, meteorologist-in-charge at NOAA’s National Weather Service forecast office in Monterey, was an “atmospheric river,” the meteorological phenomenon that draws water vapor from the Pacific Ocean near the equator and transports it to the U.S. West Coast with firehose-like ferocity.

Atmospheric Rivers, or “ARs,” are technically associated with cyclones,” says Dr. Marty Ralph, Research Meteorologist at NOAA’s Earth System Research Laboratory in Boulder. “Although these cyclones are not of the iconic circular pattern commonly associated with hurricanes, they do include hurricane-strength winds and can yield rainfall comparable to that of hurricanes. The ARs in these cyclones are regions where low-altitude winds transport huge amounts of water vapor up against the mountains, which wrings out extreme rainfall.” The AR this week produced a remarkable 21 inches of rain in just one day in the mountains near Big Sur, and winds that exceeded hurricane force.

While the atmospheric river that hit central California on October 13 and 14 was large, breaking some daily rainfall records and streamflow records for this time of year on several California creeks and rivers, including the Salinas River, the Russian River, and the Merced River, according to USGS Research Hydrologist, Dr. Michael Dettinger, in many cases, the results can be much larger, especially later in the winter. Nonetheless, this AR would have been notably long and strong any time of year.

For weather experts, storms this large always bring to mind the historically massive storms that impacted both northern and southern California in 1861 and 1862, flooding the Central Valley of California, obliterating at least one community in southern California, and causing the state capital to me moved from Sacramento to San Francisco. According to scientists, storms of this magnitude will eventually happen again.

To address storms of this magnitude and help prepare emergency responders and resource managers, the USGS Multi-Hazards Demonstration Project, creators of the ShakeOut Earthquake Scenario, are working with researchers like Ralph, Dettinger and Reynolds to construct a massive, though scientifically plausible, hypothetical storm scenario, called “ARkStorm.”

The ArkStorm scenario has adapted data and information from recent U.S. West Coast storms to simulate the type of storms that impacted northern and southern California in 1861 and 1862. With the atmospheric scenario completed, experts are now examining in detail the probability, cost, and consequences of floods, landslides, coastal erosion and inundation; debris flows; environmental effects; agricultural loss; and possible physical damage such as bridge scour, road closures, dam failure, property loss, and levee-system collapse. The ARkStorm scenario is scheduled to be the basis of statewide emergency response drill in 2011.

“There is no specific scale for categorizing atmospheric rivers,” said Dale Cox, Project Manager of the USGS Multi-Hazards Demonstration Project. “We tend to call West Coast storms by the year they occurred, like 1969, 1986 and 1997. ARkStorm represent an atmospheric river (AR) with a value of 1,000 on a scale of atmospheric rivers yet to be determined by atmospheric scientists.”

In addition to the ARkStorm scenario, the USGS Multi-Hazards Demonstration Project led the creation of the ShakeOut Earthquake Scenario that became the basis of the Great ShakeOut earthquake preparedness drill last fall. They are also responsible for the multi-hazards, multi-agency, and multi-scientific discipline approach behind the recent debris flow assessment and warning system being used at the Station Fire in southern California.

“There was a unnerving convergence of coincidence, danger and irony as this atmospheric river roiled into California, threatening to cause massive debris flows, on the day of the annual Great California ShakeOut, ” said Lucy Jones, Chief Scientist of the USGS Multi-Hazards Demonstration Project, who’s home is directly below the Station Fire burn perimeter. “We just dodged a bullet.”

Read more:

http://www.usgs.gov/newsroom/article_pf.asp?ID=2327

“The Station Fire is nearly out, but the danger is far from over. Scientists at the U.S. Geological Survey say hillsides stripped bare by the flames could bring trouble from mud and debris flows this winter, even with normal rainfall.”

“The fire burned away vegetation from more 160,000 acres of the Angeles National Forest. In an interview with KPCC’s Larry Mantle, Lucy Jones with the USGS said signs of the potential danger from runoff are obvious.”

““Go look up at the mountains right now, and you can see what’s called ‘dry ravel’ has already begun,” said Jones.”

Read more:

http://www.scpr.org/news/2009/10/07/first-fire-now-mud/

“Elevating the visibility of such storms and preparing for them is particularly important in view of preliminary scientific results that suggest that the most massive of these storms may become more common and ferocious at the global climate warms,” said Michael Dettinger, a USGS Research Hydrologist at Scripps Institute of Oceanography.

Dettinger and Marty Ralph, NOAA Program Manager at Environmental Systems Research Laboratory in Boulder, Colorado, are coordinating the Atmospherics Design Section of the ARkStorm scenario and presenting preliminary findings at the symposium. The ARkStorm scenario will include contributions from experts from NOAA, USGS, Scripps, the State of California and many other organizations. Experts will examine in detail ARkStorm’s cost and its potential consequences including floods, landslides, coastal erosion and inundation, debris flows, pollution and extirpation of endangered species. Experts will further examine physical damage possibilities like bridge scour, road closures, dam failure, property loss, and levee system collapse as well as the social and economic impacts of the storm.

The term “Pineapple Express” is popularly used to describe the meteorological phenomenon that causes moisture to be drawn from the Pacific Ocean near the equator and transported to the US West Coast with fire-hose like ferocity. This meteorological phenomenon of intense wind and rain is technically associated with “extratropical cyclones.” While these cyclones are not of the simple circular patterns commonly associated with hurricanes, they do carry within them a phenomenon that is the focus of some of the most intense impacts – an “atmospherics river.” ARs have recently become observable through satellite technology.

According to Marty Ralph, “An intense atmospheric river striking the northern Sierra Nevada Mountain Range and flooding downtown Sacramento is the California analogue to Hurricane Katrina hitting the Gulf of Mexico Coast and flooding New Orleans.”

While intense ARs that produce West Coast flooding may never compare with hurricanes in the national public’s eye, they represent the West Coast analogue of hurricanes, and in key ways, Sacramento is no less at risk now than New Orleans was before Katrina. The task of ARk Storm is to elevate the visibility of the very real threats to human life, property, and ecosystems posed by extreme winter storms on the US West Coast. This enhanced visibility will help increase preparedness of the emergency management community and public to such a storm.

“High-rise steel buildings sustained less damage than unreinforced brick buildings and older concrete buildings in the analysis. But the damage they sustained was greater than expected based on the standard building design formulas.”

“”It has huge implications,” said Lucile Jones, a U.S. Geological Survey seismologist who served as chief scientist for the ShakeOut project. “When these types of buildings collapse, we could have 1,000 people in them. That’s something to worry about.”"

Read more:
http://articles.latimes.com/2009/jan/02/local/me-steeltower2

Secretary of the Interior Dirk Kempthorne joined California Gov. Arnold Schwarzenegger, U.S. Geological Survey Director Mark Myers and more than 5 million Californians in The Great Southern California Shakeout, the largest earthquake preparedness drill in U.S. history

“This is one of the most impressive and effective exercises that has ever taken place anywhere in the world,” Kempthorne said at the Holy Cross Triage Center in Mission Hills. “I say ‘exercise’ but keep in mind that the scientists would tell you it is not a question of ‘if,’ it is a question of ‘when’ a major earthquake will hit.”

When the fictional ‘earthquake’ started at 10 a.m., the Secretary was in a classroom with students at Stevenson Elementary School in Burbank. He participated in the “Drop, Cover, and Hold On,” evacuation and triage.
The USGS, an agency of the Department of the Interior, led a multi-disciplinary team of more than 300 experts from academia and industry, public and private sectors to develop the ShakeOut Scenario and communicate it to emergency managers and the general public.

The scenario depicts a magnitude 7.8 earthquake striking the Southern San Andreas Fault, starting at the Salton Sea and rupturing northward 190 miles. Kempthorne described the scenario in giving the keynote address at the Los Angeles International Earthquake Conference dinner Thursday evening.

“Think about it: 1,800 dead…53,000 injured…1,500 buildings collapsed…$213 billion in damage…thousands of fires burning out of control…two thirds of the hospital beds lost…water cut off, perhaps for months…no electricity….bridges and rail lines destroyed…telephones and other communication shut down…tens of thousands of people wandering the streets with no place to go….all needing to be housed and fed. A catastrophe that dwarfs any other kind of natural disaster,” Secretary Kempthorne told conferees.

The USGS scenario represents the most comprehensive analysis ever of what a major Southern California earthquake would mean. (See http://www.usgs.gov/shakeout and http://www.usgs.gov/homepage/science_features/shakeout.asp.)

Nov. 14, 2008
Contact: Joan Moody
202-208-6416