Mean flow and turbulence characteristics in pool-riffle structures

RODRÍGUEZ, J. F.; GARCÍA, C.M.; GARCÍA M.H.

Estes Park, Colorado.USA.

Conferencia; Hydraulic Measurements & Experimental Methods Conference; 2002

Environmental and Water Resources Institute of ASCE (EWRI) y International Association of Hydraulic Engineering and Research (IAHR)

Channelization limits the geomorphological and biological diversity of many urban streams.Whenever the existing infrastructure prevents re-alignment of the channel planform, in-channelstructures of the pool-riffle type offer an alternative means to provide some degree of variabilityin the flow pattern. This paper presents mean flow and turbulence measurements obtained on aphysical model of pool-riffle structures designed to restore low gradient streams in heavilyurbanized areas. The data collected include high-resolution 3D velocities as well as water surfaceelevations for different flow conditions. The results show that the flow is highly threedimensional,and that the effect of the structures is more important for low flow conditions. Also,flow patterns resemble that of natural pool-riffle sequences. Implications for sediment transport,bed and bank morphology and aquatic habitat are analyzed.