The hyporheic zone is a region beneath and alongside a stream bed, where there is mixing of shallow groundwater and surface water. The flow dynamics and behavior in this zone (termed hyporheic flow or underflow) is recognized to be important for surface water/groundwater interactions, as well as fish spawning, among other processes. As an innovative urban water management practice, the hyporheic zone can be designed by engineers and actively managed for improvements in both water quality and riparian habitat.
The assemblage of organisms which inhabits this zone are called hyporheos.
The term hyporheic was originally coined by Traian Orghidan in 1959 by combining two Greek words: hypo (below) and rheos (flow).
- Lawrence, J.E.; M. Skold; F.A. Hussain; D. Silverman; V.H. Resh; D.L. Sedlak; R.G. Luthy; J.E. McCray (14 August 2013). "Hyporheic Zone in Urban Streams: A Review and Opportunities for Enhancing Water Quality and Improving Aquatic Habitat by Active Management". Environmental Engineering Science. 47: 480–501. doi:10.1089/ees.2012.0235.
- Orghidan, T. (1959). "Ein neuer Lebensraum des unterirdischen Wassers: Der hyporheische Biotop". Archiv für Hydrobiologie. 55: 392–414.