Houston grew immensely when Welch was mayor.  In 1963, Houston was still considered a 'small' city, having reached one million people.  Under Welch, several events put Houston on the map, including the opening of the Astrodome and the Houston Intercontinental Airport.  NASA sent a man to the moon.  Lake Conroe and Lake Livingston opened to provide water for Houston.  Welch also closed forty inefficient sewage treatment plants, began cleaning up the Houston Ship Channel, focused on bayou beautification; and began development of the downtown Civic Center, among other accomplishments.  It should also be noted that Welch was the first Houston mayor to win all precincts during one of his reelections, including predominantly African American areas with which some claim he had trouble.