DemographicsUpper Dartbrook is approximately 224.39 square kilometres. In 2016 the population of Upper Dartbrook was 146. The population is 51% male and 49% female. On average the monthly mortgage repayments in Upper Dartbrook are $4000+. The most common weekly income bracket is $1500 to $1749 per week. Weekly rents in the area are on average $0 to $74.