DOCUMENTING AND REGULATING GEOLOGIC HAZARDS: A PRIMER FOR CITY AND COUNTY GOVERNMENTS

Following the SR 530 “Oso” Landslide in early 2014, county and city governments nationwide, and especially in Western Washington, internally assessed their knowledge of local landslides and their own liability should a similar tragedy happen in their neighborhood. In many cases, their knowledge was found to be incomplete and their regulations inconsistent with adjacent counties or cities. The question for many became “How do we address hazards like this with limited or no resources?” The answer is that there are ways geologists can cost-effectively assess the distribution and potential impact of geologic hazards of all types by relying on existing resources and looking for ways to benefit from economies of scale. New technologies (such as LiDAR) offer both inexpensive and rapid ways of assessing some hazards, and historic records can be tapped to assess others. With the advent of new technologies comes the ability to define some geologic hazards to a level of detail not possible before, and geologists and local governments might find themselves in a position of being thrust into politically compromising positions or incurring liabilities they did not anticipate. As a result, it is important to keep in mind some basic principles that will minimize future problems. To begin with, for both geologists and regulators, definitions are extremely important, both in defining which hazards to map and in drawing lines around what to regulate. Scientists and regulators have to be careful of promising too much and of condemning too much, and this is accomplished by knowing the limitations of the data and providing a good explanation to the public. Introducing new data or even re-doing old hazard maps can generate excessive public concern unless it is done with a sensitivity of the impacts to property owners. For your efforts to be considered “good government,” your work has to be scientifically valid, reasonable, rational, and responsible. It is important for local governments, and the geologists employed by them, to be very clear about what is expected of the public and to have a good reason for it. Conflict can be minimized when education is maximized, both internal and external to government agencies. Keeping the hazard in perspective, with respect to the bigger picture, is critical.