The Land Use Portfolio Model

Natural hazards threaten public safety and economic health nationwide. As people increasingly move to locations that are vulnerable to natural hazards, financial losses from natural hazard events will continue to rise. Community decision-makers and leaders face the challenge of how to plan for and allocate scarce resources to invest in protecting their communities. A well-rounded strategy to address the threat of natural hazards should integrate knowledge and techniques from many fields such as geology, hydrology, geography, mathematics, statistics, and economics. Additionally, geographic information systems (GIS) provide a framework and technology in which these disciplines can be combined to solve these types of complex, inherently spatial problems.

Western Region Geography has developed the Land Use Portfolio Model (LUPM), a tool for modeling, mapping, and communicating risk. It is designed to help public agencies and communities understand and reduce their vulnerability to, and risk of, natural hazards. The LUPM is adapted from financial-portfolio theory, a method for evaluating alternative, regional-scale investment possibilities on the basis of their estimated distributions of risk and return. Financial-portfolio theory can be linked with natural-hazard, land use, mitigation and emergency preparedness information to estimate risk to a community from natural disasters at the regional scale and to identify cost-effective pre-disaster risk-reduction policies.

The LUPM interface is shown below. Data inputs include the probability of the hazard event, the planning-time horizon, the assets at risk (e.g. tax parcels), the spatial probabilities of damage, the dollar value and/or vulnerability of each asset, and the cost and effectiveness of the risk-reduction measures being considered. To use the LUPM, the user selects a portfolio of locations and/or measures in which to invest a limited budget for hazard mitigation. Then, for that portfolio, the LUPM calculates estimates for the total cost, number of locations mitigated, return on investment, expected loss, and community wealth retained. Finally, the user can display maps showing the results of each mitigation policy, and compare and rank the policies according to their own priorities.

Ongoing research includes model development for multiple hazards, spatial dependence, and time horizons; decision-support tool software development and strategic planning; and case study applications in southern California, southern Florida, Memphis, and British Columbia, Canada.

Publication:

Bernknopf, R.L. et al, 2001. A portfolio approach to evaluating natural hazard mitigation policies: an application to lateral-spread ground failure in coastal California, in International Geology Review, Vol. 43, pp.424-440.

Bernknopf, R.L. et al, 2006. The influence of hazard models on GIS-based regional risk assessments and mitigation policies, in International Journal of Risk Assessment and Management, Vol. 6, Nos. 4/5/6, pp.369-387.

Champion, R.A., Jr. et al, in press. The Land Use Portfolio Model: A multi-disciplinary approach for natural-hazards risk assessment [abs.]: 2005 USGS Modeling Conference, Port Angeles, WA. Nov. 15-17, 2005.

Dinitz, L.B. et al, 2005. A GIS-based decision support system for evaluating alternative natural-hazard mitigation policies [abs.]: 2005 GeoTec Event, Annual Conference, Vancouver, British Columbia. Feb. 13-16, 2005.

Dinitz, L. et al, 2004. From Maps to Money: Making the Case for Cost-Beneficial Mitigation, Using Multihazard Loss Probability Maps, Proceedings: Disaster Resistant California Annual Meeting, May 2004, Sacramento, CA. (Abstract and Presentation)

Dinitz, L. et al, 2003. Evaluation of Natural Hazard Mitigation Alternatives Using a Geographic Information System and Financial Portfolio Theory, Proceedings: Disaster Resistant California Conference, April 2003, San Jose, CA, pp. 1-10.

Dinitz, L. et al, 2003. An Interactive GIS Linking Science To Natural Hazard Mitigation Decisions, Proceedings: Urban and Regional Information Systems Association (URISA) Annual Conference, October 2003, Atlanta, GA, pp. 789-799.

Wein, A.M. et al, 2005. Modeling natural hazards in Squamish, British Columbia: A workshop for planners, emergency preparedness officers and stakeholders in Squamish, September 22, 2005.

Wein, A.M. et al, 2006. Analyzing natural hazard risks for sustainable development of Squamish, British Columbia, Canada, European Geosciences Union General Assembly, Vienna, Austria, April 7, 2006.