Thursday, September 10, 2009
Image from NASA Earth Observatory
By Guy McCarthy
While an army of firefighters battles the 250-square-mile Station Fire, scientists and technicians are trying to map and quantify how much ash, mud and rock could pour out of the burned-out San Gabriel Mountains the next time heavy rains fall.
A U.S. Geological Survey Landslide Hazards team is using NASA satellite images to prepare a burn-severity map that will show probability, volume, and locations of likely debris flows and mudslides, said Sue Cannon, a USGS project manager in Golden, Colo.
"The San Gabriels have a significant history of debris flow activity after fires," Cannon said in a telephone interview. "There are so many humans at the base of the mountains who could be impacted. We want to do this quickly."
Hazard technicians plan today to start field-checking images they received from the earth-observing LANDSAT satellite on Tuesday, and they hope to have a final report and map ready for public safety agencies by next week, Cannon said.
Six years ago Cannon helped lead a team that prepared a similar report within weeks of the October 2003 Old and Grand Prix fires, which denuded a 40-mile mountain front from Upland, below the east San Gabriels, to Highland, below the San Bernardino Mountains.
The need for timely and accurate assessment of potential post-fire dangers was underscored on Christmas Day 2003, when torrential rains on burned watersheds unleashed flash floods and debris flows that killed 16 people -- including nine children -- in Waterman and Cable canyons.
Other mapping specialists working on the Station Fire and post-fire hazard studies include support technicians from Redlands-based ESRI, a producer of geographic information systems software used by the Defense Department in Iraq and Afghanistan, as well as by public safety and fire agencies in the United States.
"We have provided tech support for many of the cooperating agencies on the Station Fire," Russ Johnson, ESRI's director for public safety and homeland security programs, told City News Service. "We have provided them with USGS topographic base data for areas considered at risk.
"We will be providing the same kind of support for rehabilitation teams and burned area emergency response teams," Johnson said. "They will be able to extract from GIS (geographic information systems) imagery areas that have the most risk of debris flows and mudslides."
While the Station Fire continues burning east in wilderness areas of the Angeles National Forest, county flood control engineers are assessing the potential for post-fire mud flows from burned areas above densely populated hillside communities in La Canada Flintridge, La Crescenta and Tujunga, said Kerjon Lee, a spokesman for the Los Angeles County Department of Public Works.
Thousands of homes below the Station Fire burned areas are protected by flood control channels and basins, according to Public Works maps and records.
But many other homes built in the past 40 years may be at risk, said Doug Hamilton, an Irvine-based engineer and former consultant to the U.S. Army Corps of Engineers, which designed and built many of the flood control structures intended to protect Los Angeles from erosion disasters.
"My concern is the proximity of the fire along the edge of development that's built in the 70s, 80s and 90s," Hamilton said. "They've never seen a post-fire erosion event.
"I see these houses cut into the side of the mountain," Hamilton said. "They're built according to building code, but it's frightening to look at. If there's heavy rains, a lot of these houses are going to be difficult to protect."
The likelihood of heavy rains this fall and winter remains unclear, but local, state and federal agencies must plan for worst-case scenarios regardless of forecasts.
The El Nino pattern that sometimes serves as an accurate predictor for Southern California's winter rain season appears "weak to moderate" right now, which makes the forecast difficult to call, said Bill Patzert, a climatologist at the NASA Jet Propulsion Lab in La Canada-Flintridge.
"But all you need is a couple storms and it's a big mess," Patzert said. "Whatever we get in the way of rain, it's going to be a mess. The areas that burned, some of them hadn't burned in 40 to 60 years. One part hadn't burned in a hundred years."
Sen. Barbara Boxer, D-Calif., Tuesday encouraged U.S. Agriculture Secretary Tom Vilsack to ensure the U.S. Forest Service focuses on erosion mitigation efforts in denuded watersheds before the advent of winter rains.
"Erosion from steep hillsides will threaten water quality and often cause mudslides that damage property downstream and can seriously exacerbate flooding, as debris, mud and rocks clog flood basins," Boxer wrote in a letter to Vilsack, whose department oversees the Forest Service.
USFS Station Fire statement this afternoon:
Post Fire Watershed Rehabilitation Activities
Incident: Station Fire Wildfire
Released: 31 min. ago
What is ahead for the Angeles National Forest
The Station Fire is the largest in Los Angeles Countys recorded history and the largest in the history of the Angeles National Forest, which was established in 1892 as the Timber Land Reserve and later changed to Angeles National Forest.
As the Station Fire subsides, the ongoing concern for the forest lands north of Los Angeles heightens. Winter rain within the burned area can pose an ongoing threat to natural resources, life and property. In order to address those concerns ahead of time, the Angeles National Forest has assembled a Burned Area Emergency Response (BAER) Team to assess the damage to the watersheds, soil and natural and cultural resources. The team is comprised of specialists that are highly experienced in conducting rapid watershed assessments and analyses and include soil scientists, hydrologists, geologists, biologists, geographic information specialists, archeologists, botanists, silviculturists, and civil engineers.
The intense heat from wildfires can cause the soil to "seal" itself and water will not easily penetrate it. The water runs rapidly down streams and canyons which could cause potential flooding, mudslides, and debris flows. The BAER Team will assess the post-fire watershed conditions for any potential emergencies and recommend immediate treatments for the National Forest System lands.
The Angeles National Forest provides the Los Angeles Basin with 35% of its water supply. Four watersheds have their origins on the Angeles NF and those watersheds have all experienced different degrees of burn activity within the Station Fire. An assessment of these burned watersheds will need to be undertaken by the BAER Team to determine what methods of treatment will be effective.
Methods used after a fire to help slow the flow of water and mud slides could include erosion control protection measures, road drainage treatments, and cultural heritage resource sites protection.
Another area of concern for the Angeles National Forest is the wildlife that has been displaced. These animals have fled to the communities surrounding the forest. People can expect to see an increase in raccoons, skunks and other animals in their neighborhoods. As the forest cools down, the animals will begin to return to their normal habitat.
The Angeles National Forest will establish a cooperating group that will be able to provide a forum for local cities, towns, county, cooperating agencies; such as Natural Resources Conservation Service, LA Department of Water and Power, and Los Angeles County Flood Control to provide input into the assessment process.
NASA text with satellite image:
Two weeks after an arsonist ignited the drought-dry forest north of Los Angeles, the Station fire had become the ninth largest fire in California since 1933. On the morning of September 8, 2009, the fire had burned more than 250 square miles (about 650 square kilometers) of land, according to the Station Fire Incident Report from September 8. This image, captured by the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) on NASA’s Terra satellite on September 6, shows the extent of the burned area. The newly charred land is black in this false-color image, which was made with near infrared light. Plants are dark red, and man-made surfaces, particularly the dense urban centers of Pasadena and Burbank, are blue and white.
The burned area covers much of the San Gabriel Mountains, edging down into residential areas northwest of Pasadena. Smoke rolls off the eastern edge of the burned land. The fire was still burning, just over 50 percent contained when the image was taken. According to the incident report from September 8, the fire was pushing east into forest with no recorded fire history. The fire had previously burned through tall, thick forest that had not seen fire in the past 40 years.
The image also illustrates why fighting the Station fire has been so difficult. The fire burned over steep mountains riddled with canyons. The rugged landscape looks wrinkled, particularly in the burned area where plants no longer soften the ridgelines and canyons. The steep terrain and the fire’s extreme, unpredictable behavior led to the death of two firefighters. Nine other firefighters have been injured fighting the fire, reported the Los Angeles Times.
South and east of the fire, the Mount Wilson Communication Facility and Observatory was still surrounded by unburned forest. The historic, 105-year-old observatory hosts two large telescopes, once the world’s largest, and other instruments to study the Sun and the Universe beyond. Mount Wilson also contains communications towers that serve much of the Los Angeles region. The image shows that the fire approached the facility on two sides, but left the forest around the observatory intact.
NASA Earth Observatory page here
USFS statement on InciWeb here
Wednesday, September 2, 2009
Across Cook Canyon from Boston Avenue backfire and live fire near homes at 6:48 p.m. Tuesday Sept. 1 in Glendale - no homes were damaged or destroyed in this neighborhood authorities said
Cook Canyon next to Boston Avenue at 6:32 p.m. Tuesday Sept. 1
On Boston Avenue in Glendale at 6:15 p.m. Tuesday Sept. 1
On Boston Avenue in Glendale at 6:10 p.m. Tuesday Sept. 1
On Boston Avenue in Glendale at 6:10 p.m. Tuesday Sept. 1
Backfire activity in north Glendale at 6:04 p.m. Tuesday Sept. 1
Los Angeles County Battalion Chief Tom Ewald, left, confers with L.A. County Assistant Chief David Richardson and others during shift change at 8:35 p.m. Monday Aug. 31 on Starfall Drive off Pine Cone Road in La Crescenta
Looking west towards Station Fire at 7:19 p.m. Sunday Aug. 30 from Oak Glen
All photos by Guy McCarthy
Converted DC-10 over Pisgah Peak
6:50 p.m. Sunday Aug. 30 2009
By Guy McCarthy
Story reported, written and published Sunday Aug. 30 2009
OAK GLEN -- More than 100 Riverside County firefighters rushed today to a fast-moving wildfire just across the border in San Bernardino County that grew to 200 acres in dense chaparral and other brush, fire officials said.
The latest Southland wildfire forced the immediate mandatory evacuation of 300 residents and hundreds of tourists in the apple orchard mountain enclave of Oak Glen.
"They just evacuated us and I'm just heading out the door," said Kent Colby, 66, as he locked up at Law's Coffee Shop in the center of Oak Glen. "It really did take off fast. The whole parking lot is full of deputies. They used the loudspeakers and they went door to door."
The fire grew quickly to more than 200 acres after it was first reported at 1:45 p.m. near Potato Canyon Road and Oak Glen Road, according to Cal Fire public information officer Jason Meyer. The blaze was a few miles north of the Riverside County line.
"The most important thing is that everyone cooperate with law enforcement and public safety," Meyer said, speaking from a communications center in San Bernardino. "Everyone needs to make sure they get out of there so we can do what we have to do."
The evacuation extended to the entire town of Oak Glen, and it was mandatory, said San Bernardino County sheriff's spokeswoman Arden Wiltshire.
Potato Canyon Road is below most of the town's homes, rustic farm buildings and orchards, as well as some of the densest, oldest chaparral surrounding the town. Above Oak Glen stands densely forested Yucaipa Ridge, an area bordering the San Bernardino National Forest that has not burned in decades.
A half-dozen tanker planes were dropping retardant on the blaze while more than 25 engine crews were assigned to the attack. Many units were staging at Oak Glen Road and Bryant Street in Yucaipa, west of the fire.
"We've got decent flying conditions between here and the fire," said Ward Monroe, an air attack supervisor at the Forest Service Tanker Base at Norton Field in San Bernardino. "It's a bit hazy, but good visibility. Takes five or six minutes to fly from here."
Tanker turnaround times for landing and reloading retardant was 30 to 40 minutes, Monroe said.
The Martin Mars flying boat that has been stationed at Lake Elsinore was pulled off the Cottonwood Fire between Hemet and Idyllwild to make drops on the new fire in Oak Glen, said Forest Service information officer Robin Prince. An order had also been placed for the DC-10 tanker that made drops on the Station Fire above La Canada Flintridge and Altadena, Prince said.
Cal Fire-Riverside County units sent to the fire included six hand crews totaling about 80 firefighters, five engine crews with four firefighters to each engine and four chief officers, said Cal Fire-Riverside County Capt. Jenn Ricci.
Observers in San Gabriel Canyon
7:44 a.m. Wednesday Aug. 26 2009
By Guy McCarthy
Story reported, written and published Thursday Aug. 27 2009
SAN GABRIEL CANYON -- While more than 1,000 firefighters toiled in heat wave conditions to gain the upper hand on two mountain fires above Azusa and Altadena, a Los Angeles County deputy director of Water Resources said today the Morris Fire could adversely impact the drinking water supply for more than one million people.
Post-fire erosion and accelerated sedimentation -- not pollution -- are the primary concerns to water officials. Vast mountainsides are scorched above the man-made reservoirs in San Gabriel Canyon, and Morris Fire perimeter maps today also showed burned areas bordering both bodies of water.
With vegetation burned off an estimated 1,800 acres or more, erosion rates and volume will increase on the steepest slopes with or without rains, according to geologists and geomorphologists.
Increased erosion in burned watersheds that empty into the San Gabriel and Morris reservoirs could mean those dammed bodies of water will have to be drained and cleared of sediment far ahead of the normal schedule, said Christopher Stone, assistant deputy director for Water Resources, Los Angeles County Department of Public Works.
The same thing happened after the 2002 Curve and Williams fires, when it took three years and cost $35 million to remove 5 million cubic yards of debris from the reservoirs, Stone said.
Draining the reservoirs over long periods of time can deprive local water vendors of up to 250,000 acre-feet that could be available in normal years, Stone said.
"In an average year we drain 250,000 acre-feet out of the reservoirs to spreading grounds," Stone told City News Service. "There it percolates underground, then it's pumped out and treated for drinking water supply. An acre-foot can supply two families of four for one year."
The typical annual yield from the San Gabriel and Morris reservoirs supplies "well over a million people," Stone said.
"That's a huge impact," Stone said. "It's a situation we'll have to monitor. A trigger point for draining the reservoirs will be whether we can operate valves and gates on the dams. It will depend on the rain seasons and when we get heavy rains."
Morris Dam was built in 1934, and according to California Institute of Technology archives, Morris Reservoir was used for testing rockets and torpedoes during World War II. The Metropolitan Water District had jurisdiction for several decades, but the Los Angeles County Department of Public Works has been responsible for both dams and reservoirs since 1995.
The San Gabriel Mountains that comprise all the high ground in the Angeles National Forest are ``highly erosive" and tons of sediment come down every year in normal conditions, Stone said. The two reservoirs in San Gabriel Canyon have to be drained and cleared of sediment every 10 to 15 years in normal circumstances -- without fires, Stone said.
At the Morris Fire incident command post in Irwindale, Angeles National Forest Technician Jim Garner explained some basic geology about the eroding San Gabriels.
"These are the fastest-growing mountains in the world, I believe, and they are also the fastest disintegrating, because of the geologic uplifting, the earthquakes and the faults," Garner said, standing next to a fire perimeter map that showed parts of the Morris and the San Gabriel reservoirs. ``Even without the fires, you have a tremendous amount of sediment and material coming out of the North, West and East forks of the San Gabriel River. These are huge drainages.
"That's just in normal conditions. Now you take a fire and wipe out all that vegetation and there's nothing to hold the topsoil and sediment back," Garner said. "So when it rains it accelerates movement of debris and volume of material going into the water in those reservoirs. There will be more turbidity and silt in the water."
Los Angeles County is the custodian of the dams and reservoirs, and flood control is the primary use of the dams, Garner said.
"About every 10 to 15 years they have to drain the reservoirs and remove the silt, in normal conditions without fires," Garner said. "I do believe they get drinking water out of them."
Congressman David Dreier, R-San Dimas, who represents the 26th Congressional District that includes the areas still burning in the Morris and Station fires, visited an incident command post in Irwindale today for a briefing on the fires.
"My main concern is with 100-degree temperatures, we have two fires going and there is the threat of more fires starting in these conditions," Dreier told CNS. "There is no silver lining to these fires. The only benefit that comes is learning how to combat the next fire.
"What I'm saying should be done today is that people take precautions to protect their families, pets and property," Dreier said. "And they need to listen to law enforcement in the event evacuations become necessary."