City Floodplain Information Services

Issaquah's floodplain poses ongoing risks, with significant floods recorded in 1986, 1990, 1996, 2009, and 2020, impacting both commercial and residential properties. The most damaging floods occurred in February 1996 and January 2009, resulting in millions of dollars in losses. In response, the City has implemented flood management initiatives, such as buying out homes in vulnerable areas and improving flood-prone infrastructure. Flooding risks peak from October to April, particularly during intense rainfall or rapid snowmelt events. City officials stress the need for residents to remain prepared, as large floods can recur annually.

Recent capital improvements have totaled tens of millions of dollars, enhancing flood resilience through projects like bridge replacements and improved floodplain mapping. The City also provides a 25% discount on flood insurance due to its participation in FEMA’s Community Rating System. Building regulations in floodplains require that new developments meet specific standards to minimize flood risks.