Provide “hi-low” drinking fountain, min. 18” and max. 19” in depth with clear knee 
space between bottom of apron and floor not less than 27” high, 30” wide and 8” deep from front edge of fountain. Provide toe clearance of 9” in height above floor and 17” in depth from front edge of fountain. Provide clear floor space 30”x48”.
CBC 1115B.4.6.2 2010 ADA 602
Alcove to be not less than 32” in width and 18” deep…
CBC 1115B.4.6.3
Various manufacturers of double drinking fountains position the units tight to each other without regard to the front approach clearance of 30 inches by 48 inches (Figure 305.5 of the 2010 Standards). Has there been an interpretation that allows this condition to be accepted by all enforcing agencies?