Assessment of Interpolation Methods in Estimation of Groundwater Level (Case study: Sarkhon Plain)

Groundwater is the main source of water and determination of groundwater level is one of the most important issues in water resources engineering. Groundwater level can be estimated in every point of any aquifer using interpolation methods. In this study, four interpolation methods including IDW, SPLINE, spherical kriging and exponential Kriging were used for estimating groundwater level of the Sarkhon plain. This plain is located in Hormozgan province of Iran. Comparison of the considered methods showed that the Spherical Kriging was the best method for interpolating of groundwater level in the Sarkhon plain with Root Mean Square Error (RMSE=13.2) and Mean Absolute Error (MAE=8.5). The IDW method had the most inaccurate results. This method had the lowest R2 and highest RMSE and MAE values in comparison with the other considered interpolation methods. However, it wasn’t observed significant difference among results of the four considered methods. Zoning was done using the method described in the Sarkhon plains. It was determined that Groundwater levels in East of the plain, were lower than those in the West.