Preparing for the "Big One" -- Saving Lives Through Earthquake Mitigation in Los Angeles, CA

LIFELINES

I. Introduction

Lifelines are utility services and transportation networks vital to the health and safety of the community and the functioning of an urban, industrialized society. Effective mitigation programs that help minimize interruptions of electrical power, natural gas, and water and the delivery of essential services and foodstuffs will improve the community's ability to respond to and recover from an earthquake. The Los Angeles area's aging infrastructure is an important factor in its need for improved mitigation arrangements.

Electrical Power

The Northridge earthquake caused significant damage to the utility systems serving Los Angeles. For a brief period, the Los Angeles Department of Water and Power (LADWP) lost all power to its service area, which covers the City of Los Angeles and includes the San Fernando Valley, where the epicenter was located. In addition, the earthquake disrupted service to over 1 million of the 4.2 million customers of the Southern California Edison Company (SCE). However, the company reports that service was restored to one-fourth of these customers within a minute, service had been restored to all but 2,500 customers within 24 hours, and all service was restored to Southern California Edison customers within 56 hours of the earthquake. Overall, the utility industry concluded that electrical systems recovered exceptionally well after the Northridge earthquake.

Water Supply

The Los Angeles Department of Water and Power's water system facilities incurred extensive damage throughout the San Fernando Valley and in the Sherman Oaks area. There was also localized damage to water supply systems in the West Los Angeles area and throughout the eastern San Fernando Valley. Immediately following the earthquake, approximately 100,000 customers were without water, and a citywide "boil water" advisory was issued. Within 5 days, water service was restored to all but a few thousand customers; after 10 days, less than 100 scattered customers were without water. All "boil water" orders were lifted after 12 days. The Department of Water and Power estimates that repairs of earthquake damage to the city's water system will cost approximately $40 million.

Gas Supply

Following the Northridge earthquake, the Southern California Gas Company (SoCal Gas) reported 151,000 gas outages. The large majority of these outages were due to customer-initiated shutoff. Within three weeks, roughly 120,000 services were restored; the remaining customers were inaccessible because of earthquake damage to structures or for other reasons. In total, SoCal Gas responded to over 400,000 customer requests after the earthquake.

During the earthquake emergency, there were no gas utility incidents involving fatalities. However, gas-fed fires destroyed 23 structures and 172 mobile homes and partially damaged 28 others. SoCal Gas' main earthquake mitigation concerns pertain to manufactured home safety and water heater bracing (discussed in the previous section of this report), as well as to the vulnerability of vintage transmission pipelines. Most of the problems in these lines appear to have been related to the performance of pre-1932 oxyacetylene-welded steel pipe, which failed primarily because of poor welding associated with the joints.

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EXHIBIT 10 Conductor removed from a disabled tower at Pardee Substation, Santa Clarita, CA.

Transportation Structures

Failure of transportation infrastructure directly caused at least one death and several injuries to motorists when the Northridge earthquake struck. Portions of eight major roads leading to downtown Los Angeles were damaged; major highways and freeways collapsed. Ten freeway structures collapsed or were extensively damaged, causing widespread disruptions after the earthquake. Several interstate and State routes passing through the San Fernando Valley were closed for long-term repairs.

Structures designed to current standards appear to have performed well, suggesting that if the damaged structures had been similarly up-to-date, many of the observed failures would not have occurred. Major repairs to all damaged transportation arteries are either complete or currently underway. The total cost of demolition and repairs to state bridges and highways following the Northridge earthquake is estimated at $350 million.

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EXHIBIT 11 One example of the extensive freeway damage caused by the Northridge earthquake.

II. What Needs to Be Done?

Currently, the engineering community is exploring a variety of technical approaches to improving the seismic performance of key lifeline components. Utilities have identified system redundancy, brittle ceramic components, connections between electric components and between water tanks and piping, and the effects of soil conditions as areas requiring improvement. Damage assessments of transportation structures further confirmed that inadequate transverse reinforcement can lead to catastrophic shear failure of bridge columns. Damage to connectors and abutments also demonstrated the need for improved earthquake-resistant designs. Beyond the technical problems, the implications of aging utility and transportation infrastructure, on earthquake mitigation must also be faced.

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EXHIBIT 12 Less than 15 miles from the epicenter of the Northridge earthquake, the Sylmar converter station suffered major damage.

Aging Utility Lifelines

Older portions of power, gas, and water systems were built to seismic safety standards that are regarded today as outmoded. Some of these pre-World War II systems are sited near the governmental and financial centers of downtown Los Angeles, where outages could result in substantial economic losses. Although this earthquake did not severely affect the Los Angeles downtown area, some of its infrastructure was damaged. The Los Angeles Department of Water and Power estimates the cost to its electrical power system at $300 million for earthquake- related damage and restoration costs. Southern California Edison estimates that the total cost of damage to its plant and related losses will be approximately $50 million. As a municipal utility, the Department of Water and Power may receive $100 million from FEMA's Public Assistance program to repair damages. Southern California Edison, as a private utility company, must recover its losses from its customers.

Failures in the gas distribution network tended to occur most frequently in pre-1930s pipe. The Los Angeles Department of Water and Power (LADWP) also perceives considerable risk in their vintage substations, which range in age from 39 to 113 years. The Department has stated that 20 substations in downtown Los Angeles need to be replaced, at a cost of between $11 million and $16 million each. This estimated cost includes purchasing new property, constructing a new substation, and demolishing the old facility. The estimated cost of replacing all 20 substations is $220 million to $320 million.

Most damage to the water distribution system occurred in cast iron mains with rigid joints, as well as in old steel pipe that is subject to corrosion. The Los Angeles Department of Water and Power has over 300,000 feet (about 57 miles) of pre-1940, large-diameter steel trunklines that need to be replaced at a total cost of $300 million. In addition, many older steel water tanks need to be replaced. Not designed or constructed to withstand stresses associated with earthquakes, many of these tanks buckled at the bottom during the Northridge quake. LADWP expects to receive $75 million in FEMA Hazard Mitigation grants to help pay for station replacement, while bond issues and special rate increases will be needed to cover the cost of water system work.

Aging Transportation Lifelines

The Los Angeles metropolitan area is highly dependent on its transportation systems. The most vulnerable link in this system appears to be bridges. More than half the bridges in Los Angeles were built before 1980 and thus are presumed to be in need of seismic retrofit. However, this rough measure of susceptibility is itself an indication of the need for additional information on the seismic performance of bridge designs. A total of 701 bridges in Los Angeles and Ventura Counties are in need of an estimated $500 million in retrofitting. For the entire State, $920 million is needed for seismic retrofit of single- and multiple-column bridges, which are most susceptible to damage in the event of an earthquake. Currently, no information is available on how much funding is to be authorized for this workthe largest share of any resources will come from the State legislature, with only a small contribution from the Federal Government.

Education and Training

The development and introduction of entirely new design criteria in the past few years has left the average practicing highway engineer somewhat behind. A large number of experienced engineers have never been exposed to either dynamic or seismic design principles. Therefore, education and training programs are needed to update highway engineers on the latest seismic techniques. Correspondence courses and workshops are available, as are online computer tutorials and classroom instruction. The cost of offering these opportunities is estimated to be $350,000.

III. What Is Being Done?

Apart from some needs for mitigation activities targeted at well- defined components of Los Angeles' lifelines, a number of challenges face Los Angeles in continuing to improve coordination and planning on seismic safety issues and completing the repairing and retrofitting of structures in order to minimize loss of life in the next earthquake. A number of Federal and statewide initiatives now underway are intended to enhance existing standards and research on utility and transportation systems.

Federal Efforts

An Emergency Relief fund created by Congress in January 1994 has enabled the Los Angeles' highway system to make a rapid recovery. Federal agencies are also funding utility and infrastructure mitigation and upgrade activities at the local level and cooperating in State and local preparedness planning and infrastructure-related engineering research.

Utility Lifelines

The Federal Emergency Management Agency (FEMA), in consultation with the National Institute of Standards and Technology (NIST), is preparing to submit to Congress a Lifelines Plan for developing and adopting seismic design and construction standards for utility systems. The draft plan concludes that standards to reduce the vulnerability of utilities to earthquakes need to be defined, and that adequate knowledge exists (or can be developed within this decade) to provide a sound basis for such standards. The new standards will:

• Establish acceptable physical and performance parameters for utility systems, equipment, and materials.

• Provide a basis for communication between buyers and sellers of utility system products and services.

• Establish foundation for regulations to protect the public health, safety, and welfare.

Transportation Lifelines

The Federal Highway Administration (FHWA) responded quickly to repair area freeways after the Northridge earthquake. Innovative contracting techniques helped make it possible to reopen important arteries in record time. In several instances, the Federal Highway Administration and the California Department of Transportation (Caltrans) agreed to an expedited contracting process that permitted State highway officials to advertise and award construction contracts in 3-5 days, in contrast to the 26-40 weeks needed under normal procedures.

Immediately following the earthquake, Federico Pena, Secretary of the U.S. Department of Transportation, approved nine contracts totalling $4.1 million for demolition, debris removal, and shoring up of damaged structures. An initial $15 million in funds made available by FHWA was allocated to meet the State's needs for debris clearance and demolition on federally funded highways. Only 2 days after the earthquake, an additional $30 million was approved for a transportation recovery plan to get Los Angeles moving again.

Federal engineers are monitoring the progress of repair projects and assuring adequate State inspection, compliance with specifications and regulations, and project quality. An estimated $244 million has been obligated by the Federal Highway Administration for the repair and restoration of approximately 43 miles of roadway and 119 damaged bridges.

The U.S. Department of Commerce is also implementing an innovative program that will assist local governments in repairing and upgrading damaged public infrastructure ineligible for funding under the Federal Emergency Management Agency's Infrastructure Repair program. Local agencies may access the Department of Commerce's $50 million Infrastructure Development Fund to enlarge the scope of FEMA projects, or to develop other infrastructure repair projects designed to reposition earthquake-impacted communities for future economic growth.

State Efforts

To improve the seismic performance of lifelines, a number of statewide mitigation coordination efforts are taking place. The California Seismic Safety Commission (SSC) is involved in recommending seismic mitigation improvements and has directed the California Public Utility Commission (CPUC) which regulates the utility industry, and the California Department of Transportation (Caltrans), which administers State highway and bridge programs, to oversee the implementation of these recommendations.

California Public Utility Commission

The California Public Utility Commission is working to establish appropriate and, if possible, uniform seismic safety standards for all power and gas systems by December 1995. To date, uniform seismic safety criteria have been established and a policy on acceptable risk has been adopted. The Public Utility Commission is currently reviewing and monitoring utilities' seismic risk policies and establishing performance standards. It is also requiring each California utility to submit annual seismic preparedness reports. For fiscal year 1991-1992, the Public Utility Commission devoted an estimated total of $30,000 to earthquake hazard reduction activities; the costs to utilities are not known.

Interutility Seismic Working Group

The Interutility Seismic Working Group, an ad hoc group of utility company staff formed in 1987, meet periodically to address earthquake preparedness issues that would benefit from interutility cooperation. The Working Group also develops consistent seismic criteria, as well as sharing information and cooperating on research and joint projects.

The Working Group consists of two subgroups. The members of the electric subgroup are Pacific Gas and Electric, the Los Angeles Department of Water and Power, Southern California Edison, San Diego Gas and Electric, the Bonneville Power Authority, and British Columbia Hydro. The members of the gas subgroup are Pacific Gas and Electric, San Diego Gas and Electric, SoCal Gas, and Southwest Gas. The Working Group is developing cost-sharing arrangements and methods to ensure that needed research is relevant and carried out in a cost-effective manner.

Caltrans

Caltrans is engaged in a multi-phased seismic assessment and retrofit of all its bridges. It also administers a statewide Bridge Seismic Retrofit Program to develop revised seismic standards for the design and construction of new highway spans. This seismic research program, which targets bridges that do not meet seismic safety standards, has two components-a State highway program and a local streets and roads program. Funded activities incorporate general engineering research and seismic monitoring of transportation structures. Techniques currently being used to strengthen bridges include the placement of steel hinge restrainers to tie bridge decks to their supports.

Local Efforts

Although the Northridge quake caused significant damage, the utility industry has concluded that power, water, and gas systems recovered exceptionally well. Within 10 days, fewer than 100 scattered customers remained without water service. Most customers had electricity again within a few hours, though a few were without service for more than 2 days. For most California utilities, the 1971 San Fernando earthquake provided the impetus for new seismic design and analysis approaches for lifelines.

Since then, the utility companies have been engaged in seismic upgrading and retrofitting activities. In the mid-1980's, SoCal Gas initiated a pipe replacement program that concentrates on pre-World War II steel pipes. In the past decade, SoCal Gas has spent $200 million on pipeline replacement and rehabilitation and anticipates spending another $65 million by 1997. The electric utilities have also made substantial progress in improving the seismic performance of substations. "Live tank" circuit breakers, a primary cause of power outages during earthquakes, are being phased out and replaced by improved apparatus. The water supply industry has also steadily modified the seismic design of water facilities and taken steps to reduce seismic vulnerability of new transmission lines in order to fortify the reliability of water delivery systems.

Transportation Secretary Pena and Los Angeles Mayor Richard Riordan were driving forces in bringing the State and local governments to agreement on a plan for repairing freeways, promoting mass transit and ridesharing, and cutting Federal red tape. They quickly established an Emergency Transportation Relief Task Force to ensure a coordinated response to all emergency transportation measures. It is anticipated that State agencies, particularly those with operations located in the area of enhanced risk, will support local governments in these efforts by providing personnel and equipment.

IV. Conclusion

Lifeline systems survived and recovered from the Northridge earthquake well, and seem well positioned to meet their substantial remaining mitigation needs. Major public and private utilities in the Los Angeles area have made long-range plans for replacing aging infrastructure and undertaking other improvements. State regulators have encouraged these actions. While major utilities cooperate closely in their mitigation planning efforts, some more inclusive forum is also needed to allow participation by smaller utilities and independent power producers, who often lack the technical resources and expertise of their larger competitors.

The Emergency Relief fund made available by Congress met all highway recovery and repair needs. However, continuing research is needed on retrofit design and materials standards for highways and bridges. Particularly urgent is the need for expanded education and training opportunities to ensure that State and local highway engineers remain up-to-date on these evolving seismic safety principles and practices.

Footnotes

1. Much of the information presented in this section is based upon HUD meetings with staff from the Los Angeles Department of Water and Power, the Southern California Gas Company, and the Southern California Edison Company in July 1994.

2. Seismic Safety Commission, "Electric Utilities", Interim Background Report DBL14, July 13, 1994, p. 1.

3. Southern California Edison Company, "Northridge Earthquake After Incident Report", p. 1., March 29, 1994.

4. Robert Giles, Senior District Operations Engineer, Water Operating Division, Los Angeles Department of Water and Power, correspondence, August 29, 1994.

5. Seismic Safety Commission, "Natural Gas Pipelines", Interim Background Report DBL3, June 10, 1994, p. 4.

6. Ibid, p. 5.

7. Douglas E. Bennett, Senior Transportation Engineer, Federal Highway Administration, U.S. Department of Transportation, phone interview, August 30, 1994.

8. Ronald Tognazzini, Los Angeles Department of Water and Power, interview, July 1994.

9. Technical Council on Lifeline Earthquake Engineering, "Lifelines Conclusions/Lessons/Recommendations", American Society of Civil Engineers, August 15, 1994, p. 2.

10. "California at Risk: Reducing Earthquake Hazards 1992-1996", Seismic Safety Commission, p. 32.

11. Phone interview with Debbie Mah, Project Development, U.S. Department of Transportation, August 30, 1994.

12. "Building the Future", Fiscal Year 1991- 1992 Report to Congress, National Earthquake Hazard Reduction Program, p. 44.

13. Ibid.

14. "Six Months After the Northridge Earthquake: A Look Back at the Federal Response", Office of Management and Budget, Washington, DC, July 1994, p. 8.

15. "California at Risk; Reducing Earthquake Hazards 1992-1996", 1994 Status Report, Seismic Safety Commission, Sacramento, CA, p. 32.

16. Pacific Gas and Electric Company, memorandum, February 24, 1994.

17. Ibid, p. 8.

18. "California Earthquake Advisory Plan", Governor's Office of Emergency Services, Sacramento, CA, October 1, 1990, p. 5.