Under the New Deal of Franklin Delano Roosevelt, the federal government got involved in urban planning. 100 newly-built green suburbs were originally envisaged. The competition was narrowed to 25 urban areas and, then, to just 4. The final selections were Greenbelt, Maryland {outside Washington, DC}, Greenhills, Ohio {outside Cincinnati}, Greendale, Wisconsin {outside Milwaukee} and Greenbrook, New Jersey {outside New York City}. In mid-1936, the Greenbrook plan was dropped.

Rexford G. Tugwell, who was instrumental in the creation of America's green suburbs. Browbeaten by conservative detractors, he resigned from his federal post in late 1936.
Photo from Wikipedia 

A photo-op groundbreaking was held in June 1935 at the Greenbelt, Maryland site. Land clearing was soon underway, with actual construction commencing in October of the same year.
Photo from Library of Congress / Elmer Johnson