بررسي روند تغييرات كيفيت شيميايي منابع آب زيرزميني دشت بم و بروات طي سالهاي 1383-1376

Chemical quality change of the underground water resources of Bam and Baravat plain between 1997-2003

Introduction: Freshwater shortage and its sustainability and unsustainahility are under consideration across the world. The fact that considerable parts of Iran are located in the arid and semiarid regions, is indicative of these geographical and climatic characteristics. This descriptive study is conducted to evaluate the chemical quality of water in Barn and Baravat plain and the variations in this trend. Methods: In this investigation, 20 piezometric water wells and 10 water wells were selected in view of their dispersion in the plain, and 12 chemical parameters of water were tested according to recommended methods of STANDARD METHODS, 20°i edition during study period. The results of tests were recorded as minimum, average, and maximum of each parameter for every well in a year and the results of the year of 2003 were drawn as a diagram with the use of Schuler and Wilcox chart. Results: The quality of water as compared with standard did not show undesirability of drinking water wells, but the quality variations of both present piezometric and drinking water wells in region tend to be worse in some cases. Based on Schulerʹs classification, water from region No.1 was found to be safe for drinking, from region No.2 suitable only for emergency situations, from region No.3 unsafe for drinking purposes. According to Wilcoxʹs classification, water from region No.1 was found to he suitable for irrigation, from region No.2 for emergency purposes, and from region NO.3 unsafe for any usage. Conclusion: In order to preserve quality and to enhance the water resources of Bam and Baravat plain it is recommended to take steps towards development of watershed management programs and control of flood water for artificial recharge of the plain.