skip to main content
US FlagAn official website of the United States government
dot gov icon
Official websites use .gov
A .gov website belongs to an official government organization in the United States.
https lock icon
Secure .gov websites use HTTPS
A lock ( lock ) or https:// means you've safely connected to the .gov website. Share sensitive information only on official, secure websites.


Title: Widespread aquifer depressurization after a century of intensive groundwater use in USA
Water supplies for household use and irrigated agriculture rely on groundwater wells. When wells are drilled into a highly pressurized aquifer, groundwater may flow up the well and onto the land surface without pumping. These flowing artesian wells were common in the early 1900s in the United States before intensive groundwater withdrawals began, but their present-day prevalence remains unknown. Here, we compile and analyze ten thousand well water observations made more than a century ago. We show that flowing artesian conditions characterized ~61% of wells tapping confined aquifers before 1910, but only ~4% of wells tapping confined aquifers today. This pervasive loss of flowing artesian conditions evidences a widespread depressurization of confined aquifers after a century of intensive groundwater use in the United States. We conclude that this depressurization of confined aquifers has profoundly changed groundwater storage and flow, increasing the vulnerability of deep aquifers to pollutants and contributing to land subsidence.  more » « less
Award ID(s):
2048227
PAR ID:
10487939
Author(s) / Creator(s):
;
Publisher / Repository:
Science Advances
Date Published:
Journal Name:
Science Advances
Volume:
9
Issue:
37
ISSN:
2375-2548
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
More Like this
  1. Abstract Groundwater wells are critical infrastructure that enable the monitoring, extraction, and use of groundwater, which has important implications for the environment, water security, and economic development. Despite the importance of wells, a unified database collecting and standardizing information on the characteristics and locations of these wells across the United States has been lacking. To bridge this gap, we have created a comprehensive database of groundwater well records collected from state and federal agencies, which we call the United States Groundwater Well Database (USGWD). Presented in both tabular form and as vector points, USGWD comprises over 14.2 million well records with attributes, such as well purpose, location, depth, and capacity, for wells constructed as far back as 1763 to 2023. Rigorous cross-verification steps have been applied to ensure the accuracy of the data. The USGWD stands as a valuable tool for improving our understanding of how groundwater is accessed and managed across various regions and sectors within the United States. 
    more » « less
  2. Abstract Most stored groundwater is ‘fossil’ in its age, having been under the ground for more than ~12 thousand years. Mapping where wells tap fossil aquifers is relevant for water quality and quantity management. Nevertheless, the prevalence of wells that tap fossil aquifers is not known. Here we show that wells that are sufficiently deep to tap fossil aquifers are widespread, though they remain outnumbered by shallower wells in most areas. Moreover, the proportion of newly drilled wells that are deep enough to tap fossil aquifers has increased over recent decades. However, this widespread and increased drilling of wells into fossil aquifers is not necessarily associated with groundwater depletion, emphasizing that the presence of fossil groundwater does not necessarily indicate a non-renewable water supply. Our results highlight the importance of safeguarding fossil groundwater quality and quantity to meet present and future water demands. 
    more » « less
  3. Groundwater wells are critical infrastructure that enable the monitoring, extraction, and use of groundwater, which has important implications for the environment, water security, and economic development. Despite the importance of wells, a unified database collecting and standardizing information on the characteristics and locations of these wells across the United States has been lacking. To bridge this gap, we have created a comprehensive database of groundwater well records collected from state and federal agencies, which we call the United States Groundwater Well Database (USGWD). Presented in both tabular form and as vector points, the USGWD comprises over 14.2 million well records with attributes such as well purpose, location, depth, and capacity for wells constructed as far back as 1763 to 2023. Rigorous cross-verification steps have been applied to ensure the accuracy of the data. The USGWD stands as a valuable tool for improving our understanding of how groundwater is accessed and managed across various regions and sectors within the United States. 
    more » « less
  4. Abstract Groundwater flow direction within the critical zone of headwater catchments is often assumed to mimic land surface topographic gradients. However, groundwater hydraulic gradients are also influenced by subsurface permeability contrasts, which can result in variability in flow direction and magnitude. In this study, we investigated the relationship between shallow groundwater flow direction, surface topography, and the subsurface topography of low permeability units in a headwater catchment at the Hubbard Brook Experimental Forest (HBEF), NH. We continuously monitored shallow groundwater levels in the solum throughout several seasons in a well network (20 wells of 0.18–1.1 m depth) within the upper hillslopes of Watershed 3 of the HBEF. Water levels were also monitored in four deeper wells, screened from 2.4 to 6.9 m depth within glacial drift of the C horizon. We conducted slug tests across the well network to determine the saturated hydraulic conductivity (Ksat) of the materials surrounding each well. Results showed that under higher water table regimes, groundwater flow direction mimics surface topography, but under lower water table regimes, flow direction can deviate as much as 56 degrees from surface topography. Under these lower water table conditions, groundwater flow direction instead followed the topography of the top of the C horizon. The interquartile range ofKsatwithin the C horizon was two orders of magnitude lower than within the solum. Overall, our results suggest that the land surface topography and the top of the C horizon acted as end members defining the upper and lower bounds of flow direction variability. This suggests that temporal dynamics of groundwater flow direction should be considered when calculating hydrologic fluxes in critical zone and runoff generation studies of headwater catchments that are underlain by glacial drift. 
    more » « less
  5. Abstract Groundwater resources are vital to ecosystems and livelihoods. Excessive groundwater withdrawals can cause groundwater levels to decline1–10, resulting in seawater intrusion11, land subsidence12,13, streamflow depletion14–16and wells running dry17. However, the global pace and prevalence of local groundwater declines are poorly constrained, because in situ groundwater levels have not been synthesized at the global scale. Here we analyse in situ groundwater-level trends for 170,000 monitoring wells and 1,693 aquifer systems in countries that encompass approximately 75% of global groundwater withdrawals18. We show that rapid groundwater-level declines (>0.5 m year−1) are widespread in the twenty-first century, especially in dry regions with extensive croplands. Critically, we also show that groundwater-level declines have accelerated over the past four decades in 30% of the world’s regional aquifers. This widespread acceleration in groundwater-level deepening highlights an urgent need for more effective measures to address groundwater depletion. Our analysis also reveals specific cases in which depletion trends have reversed following policy changes, managed aquifer recharge and surface-water diversions, demonstrating the potential for depleted aquifer systems to recover. 
    more » « less