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Although there is extensive work related to design and implementation of model-driven optimal groundwater management, evaluation of the performance of those models is less reported. This hinders transferability of lessons learned and wide adoption of specific policies. This paper reports a study designed to evaluate the effectiveness of a real-time optimal groundwater management tool, optimized regional operations plan (OROP), used in the Tampa Bay region (located on the west coast of Florida in the United States) since 1998. The overarching question in this study is how different groundwater levels would have been at monitoring sites if such an operational decision-supporting tool was not implemented. The proposed framework is comprised of multiple steps, including generating a non-OROP groundwater pumping scenario that would have happened without the decision support tool in place, running a modified optimization model in retrospective mode, and comparing water level between OROP-based and non-OROP–based pumpage scenarios. The framework is applied to historical data in the past decade (2010–2019). In generating an alternative pumpage scenario, realistic model constraints (e.g., pump capacity, pipeline hydraulics, and network) were used to generate wellfield pumpage to meet demands. Wellfield pumpage is then disaggregated at individual wells. Differences in resulting water levels at monitoring wells, at multiple timescales, between the OROP and non-OROP pumpage scenarios were calculated. Results reveal that although at a weekly timescale the effectiveness of OROP seems minimal over the region, the cumulative effectiveness at the monthly and annual timescales is remarkable. It is also found that benefit of using OROP is even higher during dry seasons when groundwater levels are more critical in maintaining wetland health. The proposed framework presented in this study can be applied to other areas in evaluating groundwater management strategies. [ABSTRACT FROM AUTHOR]

With the increased emphasis on developing integrated models capable of simulating runoff through hydrologic systems that include hillslopes and wetlands, analytical solutions have become useful in analyzing and testing numerical models applied to both. An analytical solution in algebraic form is developed in this paper to describe a sinusoidal moisture profile migrating through a wetland or a hillslope, the magnitude of the peak runoff, and the phase lag. The solution is obtained for an instantaneous sinusoidal recharge signal, and results are expressed in terms of the basin geometry and flow resistance parameters. The analytical solution is used to verify the accuracy of a numerical model based on the implicit total variation diminishing Lax-Friedrichs (TVDLF) method. This method is used in the Regional Simulation Model (RSM) developed at the South Florida Water Management District (SFWMD) to simulate the complex hydrologic system of south Florida. The runoff peak, phase lag, propagation speed, and decay rate over a range of Péclet numbers are used in the comparison of analytical and numerical solutions. The numerical model using the TVDLF method is tested by applying to the Boggy Creek watershed in central Florida, and the wetland stormwater treatment area (STA)-3/4 in south Florida to simulate storm runoffs and water levels. Results show that the model using a general power-law equation to represent flow resistance, and a conceptual model consisting of a canallike drainage feature to represent rapid drainage can be used to simulate the hydrology in both the watershed and the wetland. [ABSTRACT FROM AUTHOR]