Estimate of Groundwater Recharge Based on Water Balance in The Unsaturated Soil Zone

Abstract

Groundwater management depends on the knowledge on recharge rates and water fluxes within aquifers. The recharge is one of the water cycle components most difficult to estimate. as a result, despite the chosen method, the estimates are subject to uncertainties that can be identified by means of comparison with other approaches. In this study, groundwater recharge estimates based on the water balance in the unsaturated zone is assessed. firstly, the approach is evaluated by comparing the results with those of another method. then, the estimates are used as inputs in a transient groundwater flow model in order to assess how the water table would respond to the obtained recharges rates compared to measured levels. the results suggest a good performance of the adopted approach and, despite some inherent limitations, it has advantages over other methods since the data required are easier to obtain. Keywords

An Assessment of Groundwater Recharge at a Regional Scale for Sustainable Resource Management: Province of Alicante (SE Spain)

“…The objective of this study is the assessment of annual mean recharge and the update of water budgets for the provincial aquifers. These results summarize and homogenize the results of a number of studies accomplished by DPA-using readily applicable methods without the requirements of unavailable or difficult-to-obtain data-throughout the past three decades [60][61][62][63][64][65][66][67][68][69][70][71][72][73]. Results are validated, to a certain extent, by the evolution of water table levels and are presented as maps and tables, showing the relationships between absolute recharge values and recharge rates and aquifers type and climate.…”

“…The soil water balance model has been widely used to evaluate recharge from precipitation, usually combined with GIS techniques [61,62] and flow models [63]. The code used was RENATA ("REcarga NATural de Acuíferos", translated Natural Aquifer Recharge), which was developed in Alicante (Spain) by DPA and IGME [74] and used on some small karst aquifers with good results [75].…”

Dynamic groundwater recharge simulations based on cosmic‐ray neutron sensing in a tropical wet experimental basin

“…The groundwater recharge connects the atmospheric, surface, and subsurface components of the water balance (Mohan et al., 2018), being mainly controlled by the precipitation amount and intensity, boundary layer climatology, topography, water table level, watershed geomorphology, soil and vegetation characteristics, and irrigation return flow (Jasechko et al., 2014; Moeck et al., 2020). Understanding the seasonal controls upon recharge requires its accurate estimation (Jasechko et al., 2014), which can only be obtained by experimental methods or modelling since the groundwater recharge cannot be directly measured (Melo et al., 2015).…”

“…A considerable range of experimental methods and models is available for groundwater recharge estimation at various spatiotemporal scales, whose correct selection depends on data availability, desired spatiotemporal resolution, and result representations (Walker et al., 2019). Amongst the existing approaches, the following methods are frequently used to estimate groundwater recharge: (a) monitoring of groundwater level in unconfined aquifers, such as the water table fluctuation (WTF) method (Cai & Ofterdinger, 2016; Wendland et al., 2007); (b) tracer techniques, which estimate aquifer renewal through the concentrations of chemical elements and substances in the water, such as the chloride mass‐balance method (Brunner et al., 2004; Hornero et al., 2016); (c) the water balance method, which uses the main components of the water cycle as inputs and outputs of the system (Hornero et al., 2016; Wendland et al., 2007); Darcy's law application, which uses the hydraulic gradient and conductivity to calculate the soil water percolation rates (Callahan et al., 2012; Yin et al., 2011); and (d) numerical modeling, which consists of a mathematical representation of the groundwater processes (Melo et al., 2015; Šimůnek, 2015).…”

Assessment of the potentiometric drawdown in the Guarani Aquifer System in Bauru/SP by a model of analytical elements

“…It is a sandstone aquifer located in the southern region of South America, in Brazil, Paraguay, Argentina and Uruguay. It has been referred to as a hydrostratigraphic unit composed of Botucatu and Piramboia Formations (CAVICCHIA, 2007;GUANABARA, 2011;MELO;GUANABARA, 2015;WENDLAND, , 2010.…”