HR: 15:10h
AN: H23G-07    [Abstracts]
TI: On the interaction between the Lower Jordan River and the shallow aquifer system of the Jordan Valley
AU: * Shavit, U
EM: aguri@technion.ac.il
AF: The Department of Civil and Environmental Engineering, Technion, Technion City, Haifa, 32000 Israel
AU: Polak, A
EM: amirp@technion.ac.il
AF: The Department of Civil and Environmental Engineering, Technion, Technion City, Haifa, 32000 Israel
AU: Lipetz, A
EM: avilpz@yahoo.com
AF: The Department of Civil and Environmental Engineering, Technion, Technion City, Haifa, 32000 Israel
AU: Gavrieli, I
EM: ittai.gavrieli@mail.gsi.gov.il
AF: Geological Survey of Israel, 30 Malkhe Israel St., Jerusalem, 95501 Israel
AU: Marei, A
EM: marei@planet.edu
AF: Faculty of Science and Technology, Al-Quds University, P.O Box 20002, East Jerusalem, 95501
AU: Farber, E
EM: efratfa@bgumail.bgu.ac.il
AF: Department of Geological and Environmental Sciences, Ben Gurion University, PO Box 653, Beer Sheva, 84105 Israel
AU: Vengosh, A
EM: avnerv@bgumail.bgu.ac.il
AF: Department of Geological and Environmental Sciences, Ben Gurion University, PO Box 653, Beer Sheva, 84105 Israel
AB: The study describes the hydrology and chemistry of the shallow groundwater along the west side of the Lower Jordan River in its north section, by means of piezometers installation. We have installed 7 piezometers at different locations near the west bank of the Jordan River and added five reference points inside the river itself. The immediate purpose of these installations is to measure the groundwater level, to calculate the water gradient, to estimate the amount of water that enters the river, to sample the shallow groundwater, and provide a chemical analysis of these samples. The study area was divided into three fields, north, middle, and south where in each field a number of piezometers where drilled and one or two reference points were placed in the river. The highest gradient of the hydraulic head was measured in the north field and reached 5 m over a distance of ~500 m. This may be explained by the alluvial fan of the largest stream in the area. In the middle field the gradient of the hydraulic head was between 0.6 and 0.8 m over a distance of 170 - 380 m and in the south field we measured the smallest hydraulic gradient that was less then 0.1%. The chemical characteristics of the river show a chloride decrease from ~1900 mg/L to ~1500 mg/L and then a slight increase to ~ 1600 mg/L. Since the river is not only affected by the groundwater but also by surface inputs from the west and the east, and by intensive pumping, the interpretation and the comparison between the river data and the piezometers is complex. Never the less, there is a significant difference between the three fields. Where the chloride concentration in the north field is lower than that of the river the chloride concentration in the other two fields is higher than in the river. As the gradient of the hydraulic head found in the north field is high it is likely that some part of the river modification may be attributed to the sampled water in the piezometers. On the other hand, the very high chloride concentration found in the other two fields, have only little effect on the river concentration since no significant convection influx exists and most of the processes are diffusive and slow. The sulfate concentration increases in the river from 380 mg/L to 450 mg/L. Except for one piezometer located in the middle field, all water samples that were pumped from the piezometers show higher sulfate concentration then those in the river. This significant result supports the hypothesis that the river sulfate increases due to its interaction with the surrounding groundwater system.
DE: 1829 Groundwater hydrology
DE: 1832 Groundwater transport
DE: 1871 Surface water quality
SC: Hydrology [H]
MN: 2004 AGU Fall Meeting