Blackwater, AZ has a population of 1,462 and is the 12,844th largest city in the United States. The population density is 82 per sq mi which is 42% higher than the Arizona average and 10% lower than the national average. The median age in Blackwater is 29 which is approximately 22% lower than the Arizona average of 37. In Blackwater, 25% of the population over 15 years of age are married, 78% speak English and 4% speak Spanish. 80% of Blackwater residents were born in Arizona, 16% were born out of state, 2% were born outside of the United States and 2% were foreign born.