<P> Since the late twentieth century, San Antonio has had steady population growth . The city's population has nearly doubled in 35 years, from just over 650,000 in the 1970 census to an estimated 1.2 million in 2005, through both population growth and land annexation (the latter has considerably enlarged the physical area of the city). In 1990, the United States Census Bureau reported San Antonio's population as 55.6% Hispanic, 7.0% black, and 36.2% non-Hispanic white . </P> <P> The San Antonio Missions National Historical Park and The Alamo became UNESCO World Heritage site in 2015 and the city was designated a UNESCO "City of Creativity for Gastronomy" in 2017, one of only 26 gastronomy creative cities in the world . </P> <P> San Antonio is approximately 75 miles (121 km) to the southwest of its neighboring city, Austin, the state capital, about 190 miles (310 km) west of Houston, and about 250 miles (400 km) south of the Dallas--Fort Worth area . The city has a total area of 465.4 square miles (1,205.4 km)--460.93 square miles (1,193.8 km) of which is land and 4.5 square miles (11.7 km) of water . The city sits on the Balcones Escarpment . Its altitude is 650 feet (198 m) above sea level . </P> <P> The city's primary source of drinking water is the Edwards Aquifer . Impounded in 1962 and 1969, respectively, Victor Braunig Lake and Calaveras Lake were among the first reservoirs in the country built to use recycled treated wastewater for power plant cooling, reducing the amount of groundwater needed for electrical generation . </P>

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