HR: 17:30h
AN: H24A-07    [Abstracts]
TI: The Impact of Surface/Ground Water Interactions on Wetland Hydrology
AU: * Kazezyilmaz-Alhan, C M
EM: cmk5@duke.edu
AF: Duke University, Department of Civil and Environmental Engineering, Durham, NC 27708-0287 United States
AU: Medina, M A
EM: miguel.medina@duke.edu
AF: Duke University, Department of Civil and Environmental Engineering, Durham, NC 27708-0287 United States
AB: The crucial role of surface water/ground water interactions in water resources and hydrologic applications has been taking center stage recently. The interaction of ground water occurs with all types of surface waters (e.g., streams, lakes, wetlands and reservoirs) and pollutants in either surface or ground water get mixed and the quality of both sources is affected by each other. Wetlands are land areas which are frequently transitional between uplands and flooded systems. In the last two decades, the beneficial aspects of treatment wetlands have been studied. Yet, investigating surface/ground water interactions within wetlands has only recently become a critical issue, especially in order to understand the effect of wetland hydrology on water quality. For this purpose, a comprehensive wetland model is being developed that incorporates these surface/ground water interactions. The effect of wetlands on storm water runoff is investigated by routing the overland flow through the wetland area, collecting the runoff within the stream and transporting it to the receiving water using diffusion wave routing techniques. An implicit finite difference numerical scheme is used to solve the diffusion wave formulation. The wetland model includes Thornthwaite evapotranspiration and Green-Ampt infiltration models in the water budget, in addition to rainfall and groundwater recharge/discharge terms. The exchange of water between the wetland and subsurface is represented by Darcy's Law. In addition, the newest version of the well-known EPA Stormwater Management Model (SWMM5) is incorporated into this wetland model to simulate the runoff quantity and quality flowing into the wetland area from upstream urban areas. A preliminary application of the model to the Duke University West Campus and the Duke University constructed wetland area in the Sandy Creek watershed is presented for a one-year continuous simulation. The obtained velocity profiles are used to investigate the effect of surface/ground water interactions on the concentration distribution in the wetland areas.
DE: 1829 Groundwater hydrology
DE: 1831 Groundwater quality
DE: 1860 Runoff and streamflow
DE: 1871 Surface water quality
SC: Hydrology [H]
MN: 2004 AGU Fall Meeting