Coulee Dam, WA has a population of 1,313 and is the 13,502nd largest city in the United States. The population density is 1,816 per sq mi which is 1778% higher than the Washington average and 1904% higher than the national average. The median age in Coulee Dam is 38 which is approximately equal to the Washington average of 38. In Coulee Dam, 60% of the population over 15 years of age are married, 95% speak English and 2% speak Spanish. 66% of Coulee Dam residents were born in Washington, 29% were born out of state, 1% were born outside of the United States and 4% were foreign born.