Decatur Island Real EstateDecatur Island real estate listings include condos, townhomes, and single family homes for sale. Commercial properties are also available. If you see a property you’re interested in, contact a Decatur Island real estate agent to arrange a tour today! Decatur Island, Washington has a population of 8,212. The median household income in Decatur Island, Washington is $63,950. The median household income for the surrounding county is $59,263 compared to the national median of $57,652. The median age of people living in Decatur Island is 48.6 years. Decatur Island WeatherThe average high temperature in July is 73.1 degrees, with an average low temperature in January of 36.7 degrees. The average rainfall is approximately 30.9 inches per year, with 2.4 inches of snow per year. Nearby Homes for Sale |