Estimation of Aquifer Hydraulic Parameters from Pumping Test Data Analysis: A Case Study of Baquba Shallow Unconfined Aquifer

Abstract Groundwater conditions (GWCs) of an area depends on aquifer hydraulic parameters such as storativity () or storage coefficient (), transmissivity () and hydraulic conductivity (). It plays a key role concerning- groundwater flow modeling, well performance, solute and contaminants transports assessment and also for identification of areas for additional hydrologic testing. Specifically, the geologic formation of a regions control the porosity and permeability, however, in hilly terrain prospecting ground water potential is more challenging due to its limited extent and its occurrences that are usually confined to fractures and weathered rocks. The present study, aims at estimating the hydraulic parameters through pumping test analysis to assess aquifer system formation on hilly terrain from 16 bore wells. The aforesaid parameters were examined through a case study in some selective regions of Hamirpur district of Himachal Pradesh, India. The study area is controlled under two main geological horizons that is the post-tertiary and tertiary. The papers end with comparative results of hydraulic parameters and the aquifers system formation on different GWCs which may be helpful in the outlook of sustainable groundwater resource in the regions.

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Optimal estimation of unconfined aquifer parameters in uncertain environment based on fuzzy transformation method

Water Science & Technology Water Supply ◽

10.2166/ws.2018.089 ◽

2018 ◽

Vol 19 (2) ◽

pp. 444-450

Author(s):

Atefeh Delnaz ◽

Gholamreza Rakhshandehroo ◽

Mohammad Reza Nikoo

Keyword(s):

Test Data ◽

Statistical Error ◽

Optimal Estimation ◽

Pumping Test ◽

Transformation Method ◽

Unconfined Aquifer ◽

Uncertain Variable ◽

Specific Yield ◽

Pumping Rate ◽

Fuzzy Transformation

Abstract In this paper, a fuzzy simulation–optimization model coupled with the genetic algorithm based on Boulton's equation is presented to estimate transmissibility (T), storage coefficient (S), specific yield (Sy) and leakage factor (Dt) of an unconfined aquifer. This model is capable of minimizing the deviation between observed and calculated drawdowns of pumping test data. To assess the applicability of the model, its results are compared with the graphically obtained solutions from Boulton's equation. To this end, real pumping test data obtained from an unconfined aquifer in Dayton, Ohio, are considered as the case problem to evaluate the efficacy of the model. In the fuzzy approach, pumping rate is considered as an uncertain variable. For evaluation of the model, several statistical error indices are utilized. Results show better matches for the model as evidenced by much smaller errors. As an example, mean absolute relative error for the proposed model and graphical Boulton's solution is 2.52% and 4.98%, respectively. It is concluded that the model is accurate and may replace the graphical Boulton's solution. T and Sy were found to be more sensitive to uncertainty in the pumping rate measurement, when compared with S and r/Dt.

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