Impact of Droughts on Water Supply in U.S. Watersheds: The Role of Renewable Surface and Groundwater Resources

Abstract

We use a simplified water supply system model based on the water availability assessment via the Variable Infiltration Capacity (VIC) hydrologic model to analyze water supply droughts (WSDs), which are periods with deficient water supply. The model is applied to 27 representative watersheds of the contiguous U.S. to explore how different management strategies can be more effective in mitigating WSDs in watersheds with different drought propagation mechanisms. We find that water supply deficits during droughts (WSDDs) are generally the highest in the Great Plains watersheds, followed by the western U.S. watersheds, and lowest in the eastern U.S. watersheds. We show that different measures can be adopted to mitigate WSDs in different regions. Specifically, in the western U.S. watersheds, the conjunctive use of surface and groundwater can reduce WSDD, that is, increasing surface water utilization and using groundwater recharged through winter precipitation to supplement surface water supply during droughts. In the Great Plains region, water demands need to be brought down to sustainable levels; meanwhile switching from groundwater to surface water supply can significantly reduce WSDD as the alluvial aquifers in this region provide a stable baseflow, which can act as a steady source of water supply during droughts. In the eastern U.S. watersheds, the depletion of limited storage capacity during droughts can lead to WSDD for short periods of time, which highlights the need for expansion of storage capacity in this region.

Megadroughts in the Common Era and the Anthropocene

“…Water management further complicates the picture of how future droughts and megadroughts are likely to affect human water resources, demand, and con sumption. Activities such as surface reservoir storage and management, irrigation, and sustainable groundwa ter management are all invaluable interventions that can increase drought resilience 202,[243][244][245][246] . However, it is unclear whether current implementations of these policies will be sufficient to adapt to a warmer and drier future, espe cially because adaptive capacities have generally not been tested in the context of megadroughts.…”

Climate-catchment-soil control on hydrological droughts in peninsular India

“…In particular, it is anticipated that a better understanding of the physical processes of detecting drought characteristics will lead to improved water resources management and aid in forecasting efforts during water stress episodes in the future. Unlike several studies that relied on model-simulated records for streamflow drought assessments 94 , 95 , our observation-based synthesis enables robust risk assessment, effective in impact, adaptation, and vulnerability (IAV) studies in a changing climate. Our study helps resolve the recent debates about drought characteristics over tropical catchments, especially the recovery phase, and highlights the importance of accounting for a holistic approach involving climate-catchment-and-soil feedback to understand drought propagation.…”

Physiological and Productivity Responses in Two Chili Pepper Morphotypes (Capsicum annuum L.) under Different Soil Moisture Contents

“…It is sensitive to low temperatures with an optimum of 20-26 • C, and it requires fertile soils with mulch, adequate plant nutrition, and permanent water supply due to its high sensitivity to water deficits [16]. Water availability is one of the biggest risks in crop production, due to the high frequency of droughts in the main hydrological watershed of agricultural areas [17].…”