DemographicsSaltwater River is approximately 34.82 square kilometres. In 2016 the population of Saltwater River was 123. The population is 56% male and 44% female. On average the monthly mortgage repayments in Saltwater River are $600 to $799. The most common weekly income bracket is $300 to $399 per week. Weekly rents in the area are on average $150 to $199.