Nowa metoda pomiaru współczynnika filtracji osadów dennych

Interaction of surface water and groundwater is an important element of issue in hydrogeological measurements. Surface water may infiltrate into the subsurface through the bed sediments of rivers and water reservoirs. An opposite direction of reverse water flow through these sediments is also possible with groundwater seeping into surface water. The paper presents two new measuring apparatus: a so-called “filtrometer” and a “gradientmeter”. The filtrometer enables measuring the intensity of water filtration through bed sediments, both during drainage and infiltration. The gradientmeter is designed to measure the hydraulic gradient in the bed sediments. After measuring both of these parameters, it is possible to determine the in situ hydraulic conductivity of these sediments. Usability testing of the new devices was performed under field conditions. The filtrometer and the gradientmeter were used to determine the drainage conditions of a tested section of the Parsêta river. The drainage volume measured with the instruments was in good agreement accordance with the value obtained using the differential water flow method. The proposed new method way of determining the hydraulic parameters of the bed sediments extends the present scope of hydrogeological research.