M. K. Bara, Y. Veliskova, R. Dulovicova, R. Schugerl
Monday 5 August 2013 by Libadmin2013

References: 13th SGEM GeoConference on Water Resources. Forest, Marine And Ocean Ecosystems, www.sgem.org, SGEM2013 Conference Proceedings, ISBN 978-619-7105-02-5 / ISSN 1314-2704, June 16-22, 2013, 401 - 408 pp


Water is essential for life on Earth. Surface water (SW) and groundwater (GW) are the main sources for drinking water supply and important resources also for industry and agriculture. These two components of the hydrological cycle are interconnected and affecting each other, as well as the natural environment. During SW-GW interaction the water quality and quantity can change considerably. The EU Water Framework Directive (WFD) addressed the need of a sustainable management of coupled GW-SW resources and their ecosystems. The WFD recommends estimating the exchange flow rates and flow directions between SW and GW. This requires an enhanced knowledge of these systems. The exchange of water, solutes and colloids between SW and GW, or the hyporheic exchange, perform through the hyporheic zone. The stream hydrology and morphology significantly influence the spatial patterns of this exchange. Moreover stream-aquifer interactions are also influenced by riverbed clogging processes. The infiltration or drainage resistance of rivers influence the duration of hyporheic exchange. The value of these two parameters primarily depends on the clogging processes and the thickness of riverbed sediments. In this study, the interaction between GW and SW and the dynamics of flow processes in the GW-SW system was modelled for different infiltration and drainage resistance parameters. The model area is situated on the Rye Island, which is a lowland area with very low slope. In this area a channel network was built up, which serves for drainage. Because of the low slope and the system of water gates built on the channels, the riverbeds are influenced by intensive clogging processes. The objective of this study was to measure the thickness of riverbed sediments and to model their influence on the GW-SW interaction in the study area. The groundwater heads and the groundwater flow direction were simulated for different infiltration/drainage resistance parameters of the rivers.

Keywords: surface water – groundwater interaction, riverbed clogging, infiltration/drainage resistance of rivers