THE CRITICAL RISE SPEED OF OPEN WATER BODIES CONNECTED TO AQUIFERS

The dynamics of surface water-subsurface system are of interest in many applications. We have investigated in previous works the effects of the falling speed of the open water on subsurface hydraulics. This study focuses on the hydraulics affected by the rising speed. We used for this purpose the two-dimensional model (vertical) for variably-saturated flow in anisotropic media, MARUN (Boufadel et al., 1999, J. Contaminant Hydrology, 37, 1-20). The results indicate that the rising speed above which surface water enters the subsurface is greatly dependent on the slope of the boundary between the two media (an expected result), and on the height of the capillary fringe. The results are presented using a novel dimensionless formulation for variably-saturated flows. The results have direct implications for bank storage and water flow in tidally-influenced beaches.