Omid Rahmati; Aliakbar Nazari Samani; Mohammad Mahdavi
Abstract
Determination of groundwater potential in respect to increasing trend of water demand in Iran, is found to be an unavoidable and vital subject. The present research was aimed to assess the efficiency analytical hierarchical process (AHP) to identify potential groundwater zones. Initially, five parameters ...
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Determination of groundwater potential in respect to increasing trend of water demand in Iran, is found to be an unavoidable and vital subject. The present research was aimed to assess the efficiency analytical hierarchical process (AHP) to identify potential groundwater zones. Initially, five parameters (viz., lithology, annual rainfall, drainage density, lineament density and land slope) were used in Ghorveh-Dehgalan plain. Influencing groundwater potential were selected. A questionnaire was prepared to collect ten experts attitudes to paired comparison of such parameters. The normalized weights of criteria/parameters were determined based on Saaty’s 9 point scale and its importance in specifying groundwater potential zones using analytical hierarchy process (AHP) and eigenvector method. To prepare lineament distribution maps, ETM+ Landsat images and PCI Geomatica were applied. Finally, the set of criteria were integrated by weighted linear combination method using ArcGIS 9.3 software to generate groundwater potential prediction map. The pumping test results collected and overlaid with groundwater potential prediction map. The validation of the groundwater potential prediction map was conducted based on frequency ratio and results of pumping 20 wells in study area. Results from comparing predicted potential of groundwater and by the groundwater specific capacity (SPC) showed 85% accuracy. It was established in the study that the AHP technique is promising of make accurate and reliable prediction, specifically in no-data aquifers.
Omid Rahmati; Aliakbar Nazari Samani; Nariman Mahmoodi; bahram choubin
Abstract
One of the techniques to eliminate groundwater resources crisis is to carry out artificial recharge projects, which cause infiltration of water from the surface into the aquifer and balance of the water table. An appropriate site selection for artificial recharge is one of the most important steps in ...
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One of the techniques to eliminate groundwater resources crisis is to carry out artificial recharge projects, which cause infiltration of water from the surface into the aquifer and balance of the water table. An appropriate site selection for artificial recharge is one of the most important steps in implementation of these projects, itself. In this study, capability of gridding technique and AHP method was evaluated for zonation of artificial recharge potential. Accordingly, a grid, with cell size 0.1 km2, was defined for rangelands of Chamshor watershed and geological parameters, slope, thickness of unsaturated layer, electrical conductivity and transmissivity were selected for entry into the model. Finally, potential zonation map of artificial recharge project, using gridding technique, Analytical Hierarchy Process (AHP) and weighting linear combination methods were produced for implementation of artificial recharge. In order to assess the model, the project of artificial recharge in the study area was used which has had a successful performance on balancing the water table level, reducing destructive floods and increasing vegetation. Finally, the accuracy of the gridding technique and AHP method was 87.5 percent. In conclusion, the zonation of artificial recharge potential which was obtained by gridding technique and AHP method was reliable and it is recommended to be used in the site selection of flood spreading systems to be able to carry out artificial recharge projects.
