A review on the state of knowledge, conceptual and theoretical contentions of major theories and principles governing groundwater flow modeling

Abstract

Decision-makers require correct and adequate information on groundwater flow systems in a basin in order to formulate sustainable water resources development strategies. However, the practicality and realism of groundwater flow system models depend on the validity, reliability and availability of quality data and information, and how they are used in model development and calibration. This goes hand in hand with how the underlying theories, tenets and assumptions are understood, interpreted and applied. The more uncertain and contentious the information is, the wider are the knowledge and theoretical gaps, and thus the less useful the model results are for decision-making. The understanding of water table types in groundwater basins has become one of the additional factors for an in-depth understanding and modeling of nested groundwater flow systems. The classification of water table types using a water table ratio provides that if the ratio is more than 1, this depicts a topography-controlled area and a ratio of less than 1 depicts a recharge-controlled terrain. Log transformation of the water table ratio proved the same interpretation. This paper therefore reviews the evolution of groundwater flow systems theory, the prevailing knowledge and theoretical gaps by specifically pinpointing the theoretical and conceptual contentions and additional factors which can possibly limit the application of groundwater flow theories in regional groundwater modeling studies. The implications of how the conceptual and theoretical contentions affect groundwater modeling for decision-making in groundwater development and management are also pinpointed in this paper.