Hydrochemical and hydrogeological studies of groundwater in Peshawar Valley, Pakistan
Abstract
In September 1988 a comprehensive three months programme for hydrogeochemical groundwater investigations in Peshawar Valley in the North West Frontier Province (NWFP) of Pakistan was carried out. Its main aim was to classify the groundwater chemically in order to limelight the regional differences and highlight problems related 10 drinking and irrigation water in the region. About 100 water samples were collected from wells and analyzed. The elevation of the groundwater table and the depth to the groundwater table were measured. These data show that the water table in Peshawar Valley is < 5m deep, except in areas near the mountains and in the southeast where it ranges from 5 to > 30m. There is a general groundwater flow towards the centre of the basin from where the discharge is towards the Indus Valley. It has been noticed that the electrical conductivity (EC-values) increases from < 800 S/cm near the mountains to a maximum of 7800 S/cm in the centre of the basin. Similar is the case of mineralization.
The groundwater has been classified according 10 PIPER. In Peshawar Basin predominantly low mineralized groundwaters of the type "normal alkaline earth freshwater prevailing hydrogencarbonatic" and "normal alkaline earth freshwater with higher contents of alkalies prevailing hydrogencarbonatic " are present. These groundwaters are of good quality. Only in its central part highly mineralized groundwater of the type "alkaline freshwater either hydrogencarbonatic or sulfatic-chlorotic" are found. This high mineralizalion in Combination with the low depth of the groundwater table causes salificalion of the soils in the centre of Peshawar Basin, i.e. Risalpur and its surroundings. It is concluded that the use of such highly mineralized drinking and irrigation water should be abandoned as soon as possible because of the expected hazards to human health and irrigation. It is highly recommended that deeper wells should be drilled to find low mineralized groundwater in this area.
References
Bundschuh, J., 1989. Introduction to quantitative water analysis: a practical guide for hydrogeologists. Institute of Geology and Palaeontology, TÜbingen, West Germany, 54p.
FAO, 1986. Codex Alimentarius: methods of analysis for natural mineral Waters. Food and Agriculture Organization of the United Nations, Rome, Italy.
Frescnius, W., Quentin, K. E. & Schneider, W., 1988. Water Analysis: A practical guide to physico-chemical, chemical and microbiological water examination and quality assurance. Berlin (Springer), 804p.
Rafiq. M., Ahmad, I. & Tahirkheli., T., 1983. A geological map of the surrounding of the Peshawar plain. Geol. Bull. Univ. Peshawar, 6, 189.
U.S. Environmental Protection Agency, 1976. Quality criteria for water. Office of Water and Hazardous Materials, Washington, D.C., 256p.
