The subsurface flow emerges from the hyporheic zone in Black Dragon Wash, Utah, and supports periphyton growth for a short period. The subsurface flow is important for aquatic organisms such as aquatic insects and bacteria. In these arid environments the riparian vegetation is dependent on the subsurface water during the dry summer when the surface canalized flow is dry.


Photo: 22 April 2007, San Rafael Swell, Utah