is one of several created by Ian Rees, as Swamplot explains:
Using data from the American Community Survey, Rees mapped structures in the region by the decade they were built, grading their concentration with varying shades of blue. The result helps us visualize the decades-long march of Houston housing ever outward.Because the shading is based on housing density, darker tracts generally indicate areas where significant apartment, condominium and townhome development occurred. This map illustrates the explosion of that type of development on the western and southwestern side of town in the 60s and 70s, which ended up giving us urban artifacts such as the Gulfton Ghetto after the oil bust of the 80s. The emergence, starting in the 1970s, of suburban "master-planned" communities such as Friendswood, Kingwood, Cinco Ranch, The Woodlands and Clear Lake City is also perceptible. Finally, this map shows how denser redevelopment returned to areas inside the loop (especially areas west of downtown) after 1990; this trend continues today.
With the metropolitan area continuing to add people, jobs and houses at a rapid pace, and with no geographic boundaries to contain it, this sprawling development pattern is likely to continue into future decades. Barring some significant social or economic upheaval, of course.