a study of the relationship between the exploitation and subsidence of salmas

salmas plain is located at the west of uremia lake and at the 75 km of north of uremia city. the main river of the plain, called zulachai, is drained into uremia lake. salmas aquifer is one of the coastal aquifers of uremia lake and has hydraulic connection with the lake. the recent draught occurrences and increased water consumption in agriculture and drinking sections water have not only caused regression of lake water, but also effected on coastal aquifer, such as salmas plain aquifer. over the long-term, average groundwater level in the salmas aquifer has dropped sharply to 18/05 meters (averaging about 0/44 meters per year) and there has been 241 million cubic meters of reservoir capacity reduction. salmas plain has two confined and unconfined aquifers. salmas annual depletion of groundwater resources in the study area during the water years of 2014-15 has been equal to 146 million cubic meters. the effects of land subsidence have been observed in some output areas (kalshan and qareh qeshlaq areas).