Mary C. Comerio

Housing Issues After Disasters

Since 1989, earthquakes and hurricanes in the United States have caused housing losses on the same scale as those typically experienced in disasters in under-developed countries. While casualties in the American disasters have been low, the costs of reconstruction have been staggering. This paper documents the housing losses and recovery problems in the Northridge earthquake and compares that experience to other American urban disasters (the Loma Prieta earthquake, Hurricanes Hugo and Andrew), as well as with those in Mexico City and Kobe, Japan. The paper will demonstrate that the common denominator in urban disasters is housing and that recovery issues are quite different in cities than in rural areas, precisely because the losses are concentrated in densely populated areas and the housing loss not only represents a significant financial investment, but also a unique component of the urban infrastructure.

Estimating Downtime in Loss Modeling

Downtime includes the time necessary to plan, finance, and complete repairs on facilities damaged in earthquakes or other disasters. It is an essential component of loss modeling, because it is one measure of operational failure in lifelines and business interruption in buildings. Data from building repairs after the Loma Prieta and Northridge earthquakes, together with institutional risk management projections are used to define the rational and irrational components of downtime for buildings. Rational components include construction costs and time. Irrational situation-specific components take into account the time needed to mobilize for repairs and include financing, relocation of functions, workforce availability, regulatory changes, and economic uncertainty. To quantify these factors, the pace of recovery can be linked to the scale of damage in a stock of buildings in the affected region.

Overview of the 2010 Haiti Earthquake

The 12 January 2010 Mw 7.0 earthquake in the Republic of Haiti caused an estimated 300,000 deaths, displaced more than a million people, and damaged nearly half of all structures in the epicentral area. We provide an overview of the historical, seismological, geotechnical, structural, lifeline-related, and socioeconomic factors that contributed to the catastrophe. We also describe some of the many challenges that must be overcome to enable Haiti to recover from this event. Detailed analyses of these issues are presented in other papers in this volume.

Earthquake Protection, 2nd Edition

The second edition of Earthquake Protection is an up-to-date primer on the full range of earthquake preparedness and planning issues. The book is comprehensive in scope, remarkably detailed, and easy to read. The book is a must for government officials, risk managers, planners, emergency managers, and teachers. It is equally valuable for earthquake engineering professionals to use as a reference guide to areas outside their own specialty.

Estimating Downtime from Data on Residential Buildings after the Northridge and Loma Prieta Earthquakes

The performance-based earthquake engineering (PBEE) methodology developed by the Pacific Earthquake Engineering Research (PEER) center uses data from recent earthquakes to calibrate its loss models. This paper describes a detailed review of building department permit data from the 1989 Loma Prieta earthquake and the 1994 Northridge earthquake. Although the data is limited to wood-framed residential structures, it provides some insight into the length of time between an event and re-occupancy. Based on a review of approximately 4,900 records, the typical repair of damaged multifamily residential buildings required two years and building replacement required almost four years. When this data is supplemented with additional case studies from other events, the capacity to better calibrate downtime models will improve, particularly if construction-repair times are separated from estimates of the time gap between closure and start-of-repair.

Housing recovery lessons from Chile

Problem, research strategy and findings: The 8.8 magnitude earthquake and subsequent tsunami that struck south-central Chile on February 27, 2010, affected 75% of the countrys population and damaged or destroyed 370,000 housing units (about 10% of the housing in six regions). Within six months, the Ministry of Housing and Urban Development published a plan to repair or rebuild 220,000 units of low- and middle-income housing with government assistance within four years. By February 2014, 94% of the housing was complete. The successful rebuilding effort had strong leadership at the national and local levels and used existing programs and institutions. The management staff adapted programs over time to meet the needs of local conditions. When compared with housing recovery programs in other countries, Chiles program stands out, combining national government management with local citizen input. The reconstruction plan also included updated zoning plans, road and infrastructure improvements, heritage recovery, and new master plans for affected cities. Going forward, the earthquake created an opportunity for Chile to use the recovery planning to expand national urban policy and to develop a framework for citizen participation at the local level. Takeaway for practice: Successful planning in disaster recovery involves strong government leadership and coordination together with the engagement of local government and the participation of citizens.

Impacts of the Los Angeles Retrofit Ordinance on Residential Buildings

The Los Angeles Earthquake Hazards Reduction Ordinance, enacted in 1981 required owners of all unreinforced masonry (URM) buildings to comply with retroactive seismic standards. Among the 8100 URM buildings are approximately 1600 residential buildings with 46,000 housing units. As of March 1991, 55% are complete, 13% are in progress, 12% have been demolished and 20% have not complied. Data kept by the city shows the average cost per unit to be about

Laboratory Equipment: Estimating Losses and Mitigation Costs

6000, and the average rent increase for tenants to be

Earthquake Loss Estimates and Policy Implications for Nonductile Concrete Buildings in Los Angeles

67 per month, a 14-26% increase over pre-retrofit rents. Less than one-third of the owners completing the retrofit have applied for rent increases. Only 6% of the completed buildings have received financing assistance from the city. Two-thirds of the residential building owners appear to be finding the financing to complete the retrofit without assistance from the city but the remaining one-third of the units are at risk because owners are unable or unwilling to undertake the required work. Tenants who were forced to leave demolished or vacated units had difficulty finding replacement housing at affordable rents, and all tenants in downtown neighborhoods have been impacted by increasing rents and lost units. The Los Angeles experience is important for other cities attempting to establish ordinances and prepare policy for assisting building owners and tenants.

Moments of Resistance

The building code provides seismic design criteria for the structural and nonstructural systems in most building types, but there are no regulations to govern the installation of a buildings contents. In certain building types, such as museums, libraries, high-tech fabrication facilities, and research laboratories, the contents are valuable or critical to operations, or both. This paper focuses on strategies for improving seismic performance for laboratory furnishings and equipment. A survey of science laboratories at the University of California, Berkeley, served as the basis for constructing a simplified taxonomy of laboratory equipment, mitigation designs, and cost estimates. Case studies of five laboratories in different disciplines, and one biological science laboratory building, demonstrate mitigation techniques and potential installation costs. The case studies also highlight the importance of considering the contents separately from the structural and nonstructural systems when developing vulnerability estimates for certain building types in earthquake loss modeling.