Multivariate approaches optimize locations of groundwater pumping facilities for different hydrogeological scales

Abstract

Abstract:A number of optimization approaches regarding the design location of groundwater pumping facilities in heterogeneous porous media have elicited little discussion. However, the location of groundwater pumping facilities is an important factor because it affects water resource usage. This study applies two optimization approaches to estimate the best recharge zone and suitable locations of the pumping facilities in southwestern Taiwan for different hydrogeological scales. First, for the regional scale, this study employs numerical modelling, MODFLOW-96, to simulate groundwater direction and the optimal recharge zone in the study area. Based on the model's calibration and verification results, this study preliminarily utilizes the simulated spatial direction of groundwater and compares the safe yield for each well group in order to determine the best recharge zone. Additionally, for the local scale, the micro-hydrogeological characteristics are considered before determining the design locations of the pumping facilities. According to drawdown record data from six observation wells derived from pumping tests at the best recharge area, this study further utilizes the modified artificial neural network approach to improve the accuracy of the estimation parameters as well as to analyse the direction and anisotropy of the hydraulic conductivities of an equivalent homogeneous aquifer. The results suggested that the best locations for the pumping facilities are along the more permeable major direction.

A New Optimization Method for the Layout of Pumping Wells in Oases: Application in the Qira Oasis, Northwest China

“…Based on the Dupuit assumption, which is commonly used in the modeling of groundwater, we assumed that the phreatic water to the well is approximately horizontal and the discharge of groundwater in different cross-sectional area is equal to the flow rate of the well. The equations for the relationship between the flow-rate and drawdown of pumping-wells can be written as follows [5,[35][36][37][38], and the detailed derivation process of Equation (12) is demonstrated in the Appendix A:…”

“…After a long period of constant pumping rate, a relatively stable drawdown funnel is formed near the well. For practical purpose, the Dupuit Assumption has been applied into the phreatic water wells [35][36][37][38].…”

Optimizing layout of pumping well in irrigation district for groundwater sustainable use in northwest China

“…Others may concentrate on the relationship between groundwater depth and pumping rate under different well spatial layouts, which can optimize pumping rate and total cost. (Huang and Mayer, ; Lin et al ., ). In early studies, well layout was often optimized by establishing a typical groundwater management model, which took into account the factors of water production and drawdown and hydraulic gradients, and was usually solved by mathematical programming, such as linear and quadratic programming (Gorelick, ).…”