This study evaluates and estimates groundwater balance of the Khir plain for the period between, 1996 and 2005. The approach is centered on quantitative estimation of two main parameters-input and output. Recharge and discharge components have been quantified based on inflows, outflows and changes in the aquifer groundwater storage.The results show that the average total annual discharge of the area (119.11 MCM) exceeded total average annual recharge (106.30 MCM), implying that the system is in deficiency –an indication of unsustainable water withdrawal. The average drawdown of the water table in Khir plain was 7.08 meters in 10 years since 1996 to 2005. This not only reduces available water resources and water wells yields but can result in other serious and potentially costly side effects including saline intrusion, drying springs, and ground subsidence. Increase in pumping costs and a decline in crop yields as a result of the increasing salinity. Abstraction of groundwater could be minimized by providing sufficient canal irrigation water to the farmers , development of new irrigation networks and methods, and selection of optimal crop pattern.This study further recommend the institution of a groundwater regulatory framework to optimize groundwater use on sustainable basis and installation of groundwater recharge basin and flood water spreading.

In the current study, the qualitative status of potable well water was assessed using the groundwater quality index during a course of 4 years (2014-2017). This study was carried out with an aim to monitor the drinking water resources from 12 potable wells on the multivariate analysis basis and for determination of groundwater quality index, the following 13 physicochemical parameters including electrical conductivity, total dissolved solids, pH, total hardness, potassium, fluoride, bicarbonate, chloride, calcium, magnesium, sulphate, and nitrate were used. On the basis of Piper diagram, the results revealed that the type and faces of samples were chloride-sodic and bicarbonate-sodic respectively. Groundwater quality index level in the potable well water of case study area was 42. 89 to 56. 58 and zone water was in the good and medium range. Besides, 66. 7% of the wells were in the good range and 33. 3% of wells were in the medium range of water quality index. In this study, potassium and fluoride level in all the zone wells was lower than the ideal level and the electrical conductivity, total dissolved solids, sodium, magnesium and sulphate in all the wells was higher than the ideal range for drinking purposes. Based on this study results, the potable water quality of most of the study area wells generally in 2017 vis-à-vis 2014 had reduced and its main reason was the presence of geology formations, agricultural runoffs and absorbing wells in this zone.

In arid and semi-arid areas, water shortage leads people to the creation of traditional water management appropriate to local characteristics. Iran is one of the oldest civilizations of the world that has a unique water supply system according to social, cultural and climate condition. Indigenous knowledge-based management systems were replaced with modern management systems, and due to non-compliance modern technologies with social and environmental conditions of region, many problems have been created. The purpose of this paper was to combine traditional and modern governance rules for development of groundwater governance framework in order to achieve sustainable development. In fact, the use of culture and indigenous knowledge in the field of water resources management and retrieval new issues from new theories of governance can be the missing piece of groundwater management. In this research, the comparison of scientific documents and field observation were used to extract indigenous knowledge of sustainable groundwater governance from aqueducts management. For this purpose, at first we introduced modern system in water governance and then compared common factors with traditional governance to provide a groundwater governance framework adapted to arid and semi-arid regions. Finally, the gaps of traditional governance can be covered by combining with the principles of effective governance and then a management system adapted to climate condition. Dealing effectively with the challenges of the present era and providing appropriate development patterns will be achieved by combining indigenous knowledge with modern management.

Iran is located in an arid and semi-arid part of the world. Accordingly, the management of the water resources in the country is a priority. In this regard, determining the quality and pollution of surface water and groundwater is very important, especially in areas where groundwater resources are used for drinking. Groundwater quality index (GQI) checks the components of the available water with various quality levels. To assess the quality of drinking groundwater of Yazd-Ardakan plain according to GQI in geographical information system (GIS) environment, the electrical conductivity, sodium, calcium, magnesium, chlorine, pH, sodium adsorption ratio, bicarbonate, sulfate, potassium, water hardness, and all substances dissolved in the waters of 80 wells were determined. The samples were obtained from Yazd Regional Water Organization from 2005 to 2014. Using this data, the map components were plotted by Kriging geostatistical method. Then, the map of GQI was prepared after normalizing each map component, switching to a rating map, and extracting the weight of each component from the rating map. Based on the GQI index map, the index point which was 87 in 2005 has increased to 81 in 2014. These maps show a decline in groundwater quality from west to the east region. This decline in groundwater quality is due to the existence of Neogene Organizations in the east and geomorphologic unit of the bare epandage pediment in the west. The map removal and single-parameter sensitivity analysis showed that GQI index in Yazd-Ardakan plain is more sensitive to the components of electrical conductivity (EC), total dissolved solids (TDS), and total hardness (TH). Therefore, these components should be monitored more carefully and repeatedly.

Considering the climatic condition, drought is an inevitable phenomenon in Iran. The probability of the drought occurrence can however be predicted using the recorded meteorological data. Due to the drought importance and its impact on groundwater resources, the influence of drought on groundwater quality and ground water table of Qorveh-Chardoli plain was evaluated in this study during the last 25 years period. Monthly precipitation data (1987-2013) were applied to calculate the standardized Precipitation Index (SPI) which was then used to find the dry and wet years. Groundwater quality was also determined using electrical conductivity and sodium adsorption ratio and considering the Wilcox diagram. Kriging map of the water quality and water table were produced for wet and dry years. Groundwater quality of the Qurveh-Chardoli aquifer were classified as C2S1 and C3S1. There was no significant change in the water quality even during the wet period with raising water table. Groundwater level has changed 29.35 meters (increasing) and 13.39 meters (decreasing) during the dry and wet periods, respectively. The overall rate of decrease in the water level during the study period was 49 centimeter per year. The greatest decrease in water level were observed for eastern and southern parts of the plain.

Numerical simulation of groundwater table variations can be an effective tool for water resources management. In this study, water table variations of Shahdad aquifer located in Kerman provience, were simulated using Groundwater Modeling System (GMS) software and MODFLOW model. Changes in the aquifer water level indicate a decrease in the aquifer in the northern, eastern, southern, and some central parts of the aquifer. The developed model was calibrated using the monthly water level measurements for the period of 2012-2013 and then validated using the monthly statistics for the water year 2015-2016. Aquifer properties including hydraulic conductivity, storage coefficient, and recharge rate were estimated by inverse modeling with PEST Code. The coefficient of determination for the validation stage was calculated as 0. 95, demonstrating the good consistency of observed and predicted data and the ability of the model to predict future aquifer water table variations. A sensitivity analysis showed that the model is more sensitive to the well discharge than to surface recharge or hydraulic conductivity. Monthly reduction of discharge from wells by 30 percent can stop this phenamena.

Aim and scope: Groundwater is the most important source of water supply in arid and semi-arid regions. For this reason, its quantitative and qualitative protection plays an important role in the development of these areas. This study aimed to use groundwater quality parameters to develop a groundwater quality index. Methodology: The groundwater quality of Jiroft plain was studied using the groundwater quality index (GWQI). First, the calculation process of mentioned index was discussed and then the quality of groundwater was investigated by it. In this study, parameters such as nitrate, phosphate and arsenic were also assessed in addition to the main cations and anions of groundwater. Finding: The spatial distribution pattern of the main ions is influenced by the geological units and the direction of groundwater flow. The concentration of major and minor ions is lower than permissible limits in most parts of the plain. Conclusion: According to the results, the groundwater has good quality for drinking water in the most parts of the Jiroft plain. Groundwater recharge by surrounding alluvial fans is the main cause of the good quality of groundwater. Comparison of the map of groundwater quality index zonation with classification of groundwater samples using Schuller method shows the usefulness of groundwater quality index for evaluating the quality of groundwater.

The Groundwater Quality Index (GWQI) is used to assess the quality of groundwater and its suitability for various purposes. This index is employed by integrating data and generating a single number that reflects the overall quality of the water. In this study, changes in groundwater quality in the Qazvin aquifer were examined using GWQI over a 15-year period ending in 2021. In this regard, we used a wide range of water chemistry parameters, including Na, K, Mg, Ca, SO4, Cl, HCO3, pH, TDS, EC, and TH. The results showed that the minimum GWQI value ranged from 6.18 to 2.24, while the maximum value ranged from 1.118 to 2.205. Among the water chemistry parameters, EC and K had the highest and lowest impact on the GWQI value, respectively. The results of the Mann-Kendall trend test also indicated no significant trend in the GWQI index. Spatial analysis of the results revealed that the minimum values of GWQI were located in the northern and northwestern parts of the aquifer, while the maximum values were found in the western part of the aquifer. It is essential to note that the geographic area corresponding to the minimum GWQI values were much broader than that of the maximum values, indicating suitable groundwater quality in most regions.

Freshwater lens on small islands may easily be overexploited or polluted due to overdrafts of fresh water by pumping which causes drawdown of the water table a rise or up-coning of the saltwater interface. Present study is concerned with using a three-dimensional finite-difference numerical model to simulate the groundwater flow and transport model to predict the behavior of groundwater system in Manukan Island. The simulations were done using variable density SEAWAT-2000 for three selected pumping schemes. Hydraulic heads (groundwater level) is the highest at the center of the island and decreases in radial shape towards the coast in all the pumping schemes (PS1-PS3). The chloride concentration in the studied aquifer increased by 98.7% in the pumping well if the pumping rate is doubled by the current (PS2 to PS3). The 1.4% seawater-freshwater mixing moves further forward to inland about 1.6m when the current pumping rate was doubled whereas moves backward to sea about 1.7m if the current pumping rate is reduced by 50%. This preliminary model of Manukan island aquifer shows that an overexploitation of groundwater in Manukan Island contributes to the seawater intrusion. Adjusting the future groundwater pumping scheme and improving groundwater management strategies are necessary to protect the freshwater aquifers. The current numerical model is a reasonable representation of the aquifer in Small Island which can be used in similar small islands with similar hydrogeological conditions in elsewhere.