Quantitative and qualitative evaluation of groundwater resources and the effective factors affecting (Case study: Villages in the centeral part of Bandar Lengeh city)

Continuous monitoring of the quantity and quality of groundwater resources is essential due to the excessive dependence of employment on these resources. The present study was conducted with the aim of quantitative and qualitative study of groundwater resources in the villages of centeral part of Bandar Lengeh city. After quantitatively estimating the groundwater balance, taking into account all components of the aquifer inlet and outlet, level hydrogeological maps and groundwater level changes based on the average of the lunar data were at least in GIS software (10.3 version). By quantitative and qualitative monitoring of groundwater resources in the study area, using water quality statistics of 35 wells that were registered by the Regional Water Company during the statistical period of 2003-2018, groundwater curves were drawn and plotted. The results showed that the groundwater balance of Pedlmezan, west Dezhgan and east Dezhgan aquifers were 5.94, 0.64 and 3.24 million cubic meters per year, respectively, and the amount of allowable withdrawal from the mentioned aquifers were 5.60, 0.64 and 0.64 million cubic meters per year, respectively. Annual drop of -0.03, -0.08 and -0.07 meters of water level of Pedlmezan, west Dezhgan and east Dezhgan indicates the favorable conditions of the aquifer water balance. The qualitative results of the basin showed that the average electrical conductivity of Pedlmezan aquifer has decreased from 6935 μs⁄cm in 2007 to 5654 μs⁄cm in 2003. In Dezhgan plain aquifer, it was found that the average electrical conductivity of the aquifer has increased from 7410 μs⁄cm in 1998 to 10424 μs⁄cm in 2007. Decreasing the amount of electrical conductivity in Pedlmezan aquifer and increasing it in Dezhgan basin is directly related to fluctuations in rainfall in the relevant basin in this period. The general result of this research is that the integrated management of water resources and the measures and planning of the regions have maintained the relative balance of water balance in the region, but in order to prevent the reduction of the quality of water resources with high salinity of the basin, the ban on further exploitation of the water resources of the basin should continue.