DemographicsTonganah is approximately 31.63 square kilometres. In 2016 the population of Tonganah was 26. The population is 52% male and 48% female. On average the monthly mortgage repayments in Tonganah are $0 to $299. The most common weekly income bracket is $300 to $399 per week. Weekly rents in the area are on average $0 to $74.