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|Federal Highway Administration > Publications > Public Roads > Vol. 67 · No. 3 > Responding to an Earthquake|
Responding to an Earthquake
by Shannon McCarthy
Alaska's transportation agency shares some lessons learned about emergency response.
Tremors hit. They strike during different days of the week and different times, summer or winter, and range from a mild shake to a true world-class disaster. Despite occasional shakes, or perhaps because of them, few people are prepared to make the transition from the normal activities of their daily work lives to responding to an earthquake disaster. But emergency plans and preparedness help States, communities, and individuals make that transition more quickly, with the right tools to get the job done.
At 1:13 p.m. on Sunday, November 3, 2002, Alaska's interior shook from the State's largest earthquake in more than 30 years. At 7.9 on the Richter magnitude scale, the Denali Fault Earthquake reverberated throughout Alaska and continued releasing energy far to the southeast of its epicenter. Shocks were felt as far away as Pennsylvania and Louisiana.
Although measurable earthquakes occur in Alaska every day, officials at the Department of Transportation and Public Facilities (DOT&PF) immediately recognized that this quake was significant. They stepped into emergency response rapidly and effectively. Still, the Denali Fault Earthquake taught management and operators alike what it is like to respond to a large-scale disaster—and how to improve the planning and preparedness processes.
Alaska DOT&PF operates under two emergency plans. One is the Alaska Emergency Operations Plan, which outlines the actions that the State, local communities, and the private sector should take in the event of a disaster. The other is the State's Emergency Highway Traffic Regulation, updated in 1998, which outlines procedures for coordinating major military deployments with civilian traffic management in the event of a national emergency.
Within days after the Denali Fault Earthquake, Alaska DOT&PF moved from response to recovery. Design engineers, construction experts, and private sector contractors joined maintenance and operations personnel.
“This transition was crucial and yet the most difficult in the emergency response because it involved multiple organizations and the coordination of resources,” says Northern Region Director Andrew Niemiec. He adds, “We had a lot of experience under our belts, but some we had to gain on the job.”
The Events of Sunday, November 3
Within an hour after the earthquake occurred, a small group of Alaska DOT&PF staff, including the director of the Maintenance and Operations Division, the public information officer, and area managers, gathered at the regional headquarters in Fairbanks, AK. The group began the process of assessing the damage and reporting what they knew to Alaska State Troopers, the media, and the public. Together, they acted as the DOT&PF Emergency Operations Center.
Meanwhile, Alaska DOT&PF's maintenance managers and foremen, stationed in remote locations throughout the interior, began implementing emergency procedures. Station foreman performed Level I inspections and reported their findings to the Fairbanks office. A Level I inspection consists of a visual check of roads, bridges, and airports, looking for any signs of deformation or obstruction, such as settlement, crevices, cracks, or slides.
The maintenance crews literally responded within minutes—identifying highway, airport, and bridge damage and, in many cases, performing temporary repairs on the spot. The Alaska DOT&PF attributes the rapid response to the decentralized nature of its regional organization. Station foremen were able to complete this task within 24 hours of the earthquake, driving hundreds of miles over four of Alaska's most important roadways.
The initial inspections revealed that the earthquake damaged eight of Alaska's roads, including four of the State's major highways. They included the connectors between Alaska's two largest cities, Anchorage and Fairbanks, and the only route leading out of the State to Canada and the lower 48. Two of the highways—the George Parks and the Alaska Highway—sustained limited damage. But two other major roads—the Richardson Highway and the Tok Cutoff—were impassable for many miles.
Reopening the Richardson
The Richardson, Alaska's first highway, stretches 589 kilometers (366 miles) from Valdez to Fairbanks. Well-traveled, the highway is a particularly critical road to the Alyeska Pipeline Service Company, owners and operators of the Trans Alaska Pipeline, since the pipeline follows the route for most of its length. The Denali Fault crosses underneath the Richardson Highway to the east of the earthquake epicenter. The quake damaged more than 32 kilometers (20 miles) of the roadbed.
Alyeska shut down the pipeline as a precautionary measure. The earthquake shifted the road sideways by 2.4 meters (8 feet) at the fault line, caused rockfalls along extended sections, and left cracks up to 1.5 meters (5 feet) wide across both lanes and as deep as 2.4 meters (8 feet). Alaska DOT&PF closed the road and began temporary repairs within the hour.
Working into Sunday night, Alaska's maintenance crews cleared the road of debris, removed broken asphalt, and filled in cracks. This quick action by Alaska DOT&PF enabled Alyeska to enter the area to check the pipeline and bring in equipment to repair structural damage. The oil that flows through this pipeline for the Port of Valdez delivers 17 percent of the Nation's domestic oil supply.
“Our ability to reopen the road was critical to Alyeska's emergency response,” says Niemiec. “Shortly after midnight, we were able to
The Tok Cutoff
To the southeast of the epicenter, the Denali fault also runs under the Tok Cutoff Highway. The Tok Cutoff serves as a direct route for Anchorage and Valdez traffic accessing the Alaska Highway and is a heavily used commercial route. Damage was severe and extended for more than 81 kilometers (50 miles). The road dropped 1.8 meters (6 feet), literally collapsing extensive sections. Large cracks, ranging from inches to several feet wide and up to 3.7 meters (12 feet) deep, shattered the paved surface for miles. There was a lateral shift of 7 meters (22 feet) at the fault.
The rural communities of Mentasta, Northway, Tetlin, and Slana sustained heavy property damage. Mentasta Lake Road and Northway Road were impassable. The communities were cut off, without phones and road access, including access for emergency vehicles.
Again, the decentralized nature of the Alaska DOT&PF regional structure and delegation of authority worked well. The agency's crews were on the scene immediately. In fact, a plow truck from DOT&PF maintenance was actually on the scene when the shaking began. Slana Station Foreman Ernie Charlie radioed back to Slana for assistance and immediately organized the response in the Tok Cutoff area. He created a pioneer trail to Mentasta through the damaged sections, providing emergency access to the community.
The Alaska Highway
Maintenance crews in the area also discovered that the Northway Airport, located several miles off the Alaska Highway, was significantly damaged. The airport serves as an important customs entry for light aircraft from Canada. According to U.S. Customs, approximately 700 airplanes land at the airport each year. The earthquake created crevices over the entire 1,556-meter (5,100-foot) paved surface, a 203-millimeter (8-inch) drop along the centerline, and 0.3-meter (1-foot) heaves along the length of the runway. Foreman Gary Thomas officially closed the Northway Airport after seeing the extensive damage.
Back in Fairbanks
Back at the Emergency Operations Center, Jim Little, former maintenance director, was receiving and documenting damage reports and shifting resources to the hardest-hit areas. He was in close contact with the troopers and kept the Alyeska crews informed.
Based on these reports from the field, the public information officer began preparing a situation report and answering phone calls from the media and the public, both from Alaska and beyond. The public information officer position was a new one for the Alaska DOT&PF's Northern Region, with a staff member hired less than 2 months earlier. Having an information officer on staff relieved the maintenance director and staff members from a barrage of media requests, allowing them to focus on the task at hand—stabilizing the damaged areas.
The Days Following The Quake
Twenty-four hours after the earthquake, members of the DOT&PF Bridge Design Section began a Level II inspection, or an engineering analysis of the structures in the earthquake zone, including several bridges not owned by the State.
“Sticking to the strict lines of ownership was not advantageous to anyone,” says Richard Pratt, chief bridge engineer. “We inspected any structure in the earthquake zone. Our most important job was to stabilize the situation and give those directly affected as much peace of mind as possible.”
Flying up from Alaska's capital city of Juneau, members of the Bridge Design Section began inspecting more than 200 bridges in the earthquake zone on November 4—the day after the quake. In less than 48 hours, they completed the Level II inspections and confirmed that several bridges were damaged.
Pratt adds, “Everywhere the bridge engineers went, they saw footprints in the snow, confirming that maintenance crews had been there the day before. Not a bridge was missed by either of the teams.”
In fact, six interior bridges sustained damage. The bridge engineers recommended replacement of two spans located on the Tok Cutoff to restore structural integrity to the crossings. The bridge abutment walls had moved about 254 millimeters (10 inches) from the pressure of liquefied soil flowing toward the creek water. Although these bridges are still able to accommodate highway traffic legally, the soil movement put stress on the superstructure and left the bridges vulnerable to future earthquakes.
The DOT&PF engineers also detected shifting on the Tanana River Bridge, located at mile 1,303 on the Alaska Highway. An independent consulting firm confirmed that a span weighing more than 0.5 million kilograms (1.1 million pounds) shifted off its steel supports by nearly 102 millimeters (4 inches). The Tanana River Bridge, located about 18 kilometers (11 miles) south of Tok, was built in 1943 during the construction of the Alaska Highway. Restoration will include moving the superstructure back to its original position, installing lateral restraints, and repairing expansion joints.
In the days following the event, the DOT&PF construction employees oversaw the temporary repairs. Time was of the essence. The area had not yet received significant amounts of snow, and the temperatures remained relatively mild for an Alaskan winter. Maintenance crews needed the highways and airport restored to a condition that they would be able to maintain before the area received normal snow levels and a deeper freeze.
The DOT&PF Construction Division moved quickly and employed emergency procurement procedures to bring in contractors. Temporary repairs and reconstruction on the airport were completed 3 weeks after the initial damage, and the airport reopened to general aviation.
Temporary repairs also started on the Tok Cutoff, where damage was extensive. This reconstruction was particularly difficult, as the area continued to experience strong aftershocks in the month following the initial quake. The aftershocks prevented the soils from stabilizing. Temperatures were well below freezing, reaching as low as minus 29 degrees Celsius (minus 20 degrees Fahrenheit).
The Northway Road project was next and was completed at record pace. The DOT&PF contractors worked through the Thanksgiving weekend, and on the Tok Cutoff through the Christmas season, until the work was completed.
In the days following the earthquake, the process of documenting the damage began. Alaska DOT&PF staff worked with Karen Schmidt, assistant division administrator for the Federal Highway Administration (FHWA), to survey the damage. The work was especially difficult because of the large geographic area they had to cover in a short time.
The State also assigned staff to serve as the single point of contact for the Federal Emergency Management Agency (FEMA) and FHWA for emergency response-related repairs.
Incident Command System
The DOT&PF emergency response closely followed the Incident Command System (ICS), with the foremen functioning as onsite incident commanders. ICS is a nationally recognized method of emergency response that enables multiple organizations to provide assistance in an emergency or national disaster under a common command and control system. Alaska DOT&PF responds to emergencies year-round, including blizzards, avalanches, freezing rain, or flooding. The management structure is designed to empower onscene personnel to make decisions to get the roads open and keep the public safe.
Few Northern Region employees were actually trained in the ICS. Although the move from stabilization to recovery was relatively smooth, Alaska DOT&PF staff members were learning on the job. Several months after the earthquake, the staff took formal ICS training to prepare for the next disaster.
Preparing for Future Emergencies
Alaska was fortunate in several ways. The Denali Fault earthquake affected rural areas with small, spreadout communities. Although those communities sustained serious property damage, only one injury occurred (a woman evacuating her home). No tall buildings and no overpasses or tunnels were involved. If the earthquake had occurred closer to Fairbanks or Anchorage, the story might have been different.
Even so, the quake served as a test case for preparedness and recovery. First, the large size of the geographic region where the damage occurred is helping scientists analyze how earthquakes travel—and where structural damage can be expected. Second, the Denali Fault earthquake is serving as a test case for transportation agencies in how to respond to road and bridge damage that occurs hundreds and hundreds of miles apart.
In addition, Alaska DOT&PF learned about completing emergency repairs in winter and the problems that can appear the following spring. In this case, the November earthquake raised the water levels in the underlying soils, which subsequently refroze. (Typically during a winter freeze, the water levels drop significantly; however, with the earthquake, the water levels rose and then froze at higher levels than normal.) Spring brought a wet breakup—and soft roads that needed another round of repairs.
Alaska DOT&PF also learned lessons about disaster recovery, especially the documentation of damage for cost-recovery purposes. In a few instances, the effectiveness of the maintenance crews outpaced the agency's ability to photograph and record the damage. Although DOT&PF was able to go back to those repairs and identify the damage, more widespread damage in an urban setting could pose greater difficulties.
Finally, Alaska DOT&PF Northern Region will continue ICS training and make the training more widely available. Although the response largely resembled the ICS structure, the training will establish improved communication and partnerships with the State and Federal emergency response agencies. Dedication, care, concern, and cooperation led to Alaska's success in responding to this earthquake. However, the DOT&PF has not taken the lessons learned in this situation for granted. The earthquake represented a benchmark—a time when everyone in the State of Alaska was reminded that true disasters can strike at any time without warning. Alaska currently is fine-tuning its response system and preparing a formal written plan to save lives, minimize damages, and reduce the risks.
Shannon McCarthy is a public information officer for the Alaska DOT&PF. She has worked with the media for more than 15 years since earning her B.A. from the University of Alaska Fairbanks.
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