DemographicsBlue Rocks is approximately 7.92 square kilometres. In 2016 the population of Blue Rocks was 15. The population is 53% male and 47% female. On average the monthly mortgage repayments in Blue Rocks are $0 to $299. The most common weekly income bracket is $400 to $499 per week. Weekly rents in the area are on average $0 to $74.