With an estimated urban population of 18,588 as of June 2018, Mount Isa is the administrative, commercial and industrial centre for the state's vast north-western region. Population has decreased moderately at an average annual rate of -2.66% year-on-year over the five years to 2018. Although situated in an arid area, the artificial Lake Moondarra north of the city on the Leichhardt River provides both drinking water and an area for watersports, birdwatching and recreation. Locals often refer to Mount Isa as "The Isa".