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Howard Hanson Dam

First American Finds $30B of Properties Exposed to Howard Hanson Dam Vulnerability

Thirty-eight years ago, the Howard Hanson Dam in Washington state began water seepage in the northern abutment adjacent to the dam, which has now evolved into a potential flooding catastrophe. Following a torrential rainfall and subsequent record water volumes in the Howard Hanson Reservoir in January of 2009, the United States Army Corps of Engineers (USACE) labeled the dam as "unsafe"— a category that describes less than 5-percent of the over 80,000 dams in the U.S. that are in the very worst condition.

Currently, Federal Emergency Management Agency's (FEMA) does not reflect this potential flood risk in its flood maps. At the behest of the its insurance clients, First American Spatial Solutions analyzed multiple flood scenarios to quantify King County's overall exposure to the Howard Hanson Reservoir and to enable insurance carriers to identify their own portfolio risk. The analysis is built upon key river flow scenarios published by the USACE. Starting with these scenarios the First American's team of hydrologists and risk managers combined a series of both publically available and proprietary datasets and risk modeling tools to develop and validate multiple flood scenarios to quantify King County's overall exposure to the Howard Hanson Reservoir. First American is making this data avaialble to insurance underwriters as an enhancement to First American's Flood Risk Score (FRS) so they can utilize the results of the analysis to assess their own portfolio's risk .

To see the full report and a detailed explanation of the river flow scenarios and methodology used to model the exposure, please clink on the link below.