Track: Environmental Management

William Bajjali
Almerco Inc.
1695 Rue Atmec, Unit 8
Quebec, PQ J8P7G7

Telephone: 819-669-3170
Fax: 819-669-1922
E-mail: bajjali@almerco.ca

Using GIS to Characterize the Groundwaters in the Dhuleil, Halabat, and Samra areas of Jordan  Paper Text

Introduction: Jordan is a country located in the Middle East. It is an arid area and the desert makes up approximately 90 percent of its land mass. The amount of precipitation and the water resources are very scarce and limited. The country mainly depends on groundwater as a main source for domestic water supply and irrigation. The investigated area is about 490 km2 and is part of the Amman-Zasrqa Basin. In the middle of the 1960s a number of wells were drilled for irrigation purposes. After twnety-five years of groundwater exploitation for irrigation purposes, it has been shown that the water quality has seriously deteriorated. For instance, the salinity rose in some wells from 250 mg/l (1965) to 4,000 mg/l (1990). To find a solution to the salination problem and water table drop, Khalidieh Dam with a 1 MCM capacity was built and four wells were drilled in 1983 in order to store the floodwater in wintertime and inject it into the aquifer to improve the quality and replenish the groundwater. In 1985 Alsamara Waste Water Treatment plant (AWWTP) was built in the Samra area with a capacity of 20 MCM to treat the domestic and industrial water of the Great Amman area. The results of the study area and the GIS output maps of the salinity, nitrate, chloride, and stable isotopes show that the deterioration of groundwater is due to the return flow from irrigation and extensive fertilizer applications in Dhuleil and Halabat, while in the Samra area it is due to the effluent of wastewater from AWWTP. The evaporated irrigation water from the soil and the roots of the plants accumulate the salts in the soil, and the continuous irrigation from the same groundwater continues to dissolve the salts from the soil, which is flushed into the subsurface thereby increasing the salinity. The chloride is the major dissolved anion in the groundwater. The increased nitrate concentration measured in the groundwater wells downstream of AWWTP recorded very high values; in some wells it reached up to 300 mg/l. The stable isotopes show that the groundwater of meteoric origin and the low calculated deuterium excess (d) of some water wells is due to evaporation of the return flow before infiltration. The man-made radioactive tritium found in shallow wells in the Samra area is evidence of local recharge. Khalidieh Dam serves as an artificial recharge, replenishing local groundwater, thus improving its quality.

Copyright 1997 Environmental Systems Research Institute