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Models used for data interpretation of constant rate tests (CRTs) are commonly derived with the assumption of Darcian flow in an idealized geometry, hence disregarding the non‐Darcian nature of fluid flow and the complexity of flow geometry. In this study, an Izbash's law‐based analytical model is proposed by means of Laplace transform and linearization approximation for interpretation of non‐Darcian flow in a generalized radial formation where the flow dimension may become fractional between 1 and 3. The source storage and skin effects are also considered in the model development. The proposed model immediately reduces to Barker's (1988) model for Darcian flow in the generalized radial formation and to Wen et al.'s (2008a) model for non‐Darcian flow in a two‐dimensional confined aquifer. A comparison with numerical simulations shows that the proposed model behaves well in low non‐Darcian flow condition or at late times. The proposed model is finally applied for data interpretation of the constant rate pumping tests performed at Ploemeur, showing that the estimated hydraulic properties (i.e., hydraulic conductivity, specific storage coefficient, non‐Darcy exponent, and the dimension of flow geometry) are well representative of the hydrogeologic conditions on the field scale at the test site after the exploitation of groundwater. The proposed model is an extension of the generalized radial flow (GRF) model, which would be of significance in the problem of choosing an appropriate dimension of flow geometry in which non‐Darcian flow occurs.

The Jinping-I double-curvature arch dam, located in the middle reach of Yalong River and with a maximum height of 305 m, is the world's highest dam of this type that has been completed. Since the second stage of reservoir impounding, after which the reservoir water level was gradually raised by about 232 m, a significant amount of leakage was observed from the drainage holes drilled in the lowest drainage tunnel at the left bank abutment at an elevation of 1595 m a.s.l. (above sea level), with an observed maximum pressure of about 0.3 MPa. A number of investigations, including water quality analysis, digital borehole imaging, tunnel geological mapping, and in situ groundwater monitoring, were performed to examine the source of leaking, the groundwater flow paths, and the performance of the grouting curtains. By defining two objective functions using the in situ time series measurements of flow rate and hydraulic head, respectively, a multiobjective inverse modeling procedure was proposed to evaluate the permeability of the foundation rocks that was underestimated in the design stage. This procedure takes advantage of the orthogonal design, finite element forward modeling of the transient groundwater flow, artificial neural network, and non-dominated sorting genetic algorithm, hence significantly reducing the computational cost and improving the reliability of the inversed results. The geological structures that lead to the leakage were identified and the seepage flow behaviors in the dam foundation and the left bank abutment were assessed. Based on the field measurements and the inverse modeling results, the effects of the engineering treatments of the leakage event on the dam safety were analyzed. It has been demonstrated that the seepage control system is effective in lowering the groundwater level and limiting the amount of seepage in the dam foundation, and the leakage event does not pose a threat to the safety of the dam.

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