Experimental Investigation on the Infiltrated Water Movement in Hydraulikaly Connected Groundwater and Surface Water

Zahra Salimi1, Ali Mahdavi Mazdeh2, Stefan Wohnlich3

P 9.10 in Groundwater-surface water-interactions - processes and methods

Groundwater pollution by nitrates is one of the most significant environmental problems in the agricultural fields. Many studies have shown that agricultural activities are a significant source of surface and groundwater pollution, because of using the fertilizers. In this study, the effect of farm distance from the surface water in solute transport at the groundwater-surface water interference was investigated experimentally using creative modification on a permeability tank made of Plexiglas in the hydraulic laboratory. This tank has 20 cm width, 120 cm length and 77 cm height which filled by silica sand. It had modified to simulate a cross-section of a river/lake and agricultural lands right-hand side. The groundwater level in upstream and downstream have adjusted with two small tanks on either side of the box. In an ingenious idea, an L – shaped Plexiglas was used to separate outlet flow of river and groundwater. For pollution simulating, Potassium Permanganate were used. Experiments in different hydraulic conditions showed that most of the infiltrated solute and water from agricultural lands near the surface waters goes directly to the surface water. It shows that agricultural land near to the rivers can affect the river pollution not only with surface runoff but also through groundwater. Effect of different hydraulic gradient and slope also studied. The hydraulic behavior of infiltrated water/solute also studied using Potassium Permanganate injection. Photo digitize method used to determine advance pollution cloud.