NORTHLAKE, TEXAS. Northlake is on Interstate Highway 35W twelve miles southwest of Denton in Denton County. Although it was incorporated during the early 1960s, Northlake experienced little residential development. Its population was estimated at twenty in 1970, 143 in 1980, and 250 in 1990. The building of Alliance Airport a few miles to the south contributed to greater expansion in Northlake during the 1990s. In 2000 the population was 921.