DemographicsHighland Plains (Toowoomba - Qld) is approximately 57.86 square kilometres. In 2016 the population of Highland Plains (Toowoomba - Qld) was 41. The population is 43% male and 57% female. On average the monthly mortgage repayments in Highland Plains (Toowoomba - Qld) are $0 to $299. The most common weekly income bracket is $150 to $299 per week. Weekly rents in the area are on average $0 to $74.