Over a third of groundwater in USA public-supply aquifers is Anthropocene-age and susceptible to surface contamination

Nature Communications Earth & Environment
By: , and 

Links

Abstract

The distribution of groundwater age is useful for evaluating the susceptibility and sustainability of groundwater resources. Here, we compute the aquifer-scale cumulative distribution function to characterize the age distribution for 21 Principal Aquifers that account for ~80% of public-supply pumping in the United States. The aquifer-scale cumulative distribution function for each Principal Aquifer was derived from an ensemble of modeled age distributions (~60 samples per aquifer) based on multiple tracers: tritium, tritiogenic helium-3, sulfur hexafluoride, chlorofluorocarbons, carbon-14, and radiogenic helium-4. Nationally, the groundwater is 38% Anthropocene (since 1953), 34% Holocene (75 – 11,800 years ago), and 28% Pleistocene (>11,800 years ago). The Anthropocene fraction ranges from <5 to 100%, indicating a wide range in susceptibility to land-surface contamination. The Pleistocene fraction of groundwater exceeds 50% in 7 eastern aquifers that are predominately confined. The Holocene fraction of groundwater exceeds 50% in 5 western aquifers that are predominately unconfined. The sustainability of pumping from these Principal Aquifers depends on rates of recharge and release of groundwater stored in fine-grained layers.

Study Area

Publication type Article
Publication Subtype Journal Article
Title Over a third of groundwater in USA public-supply aquifers is Anthropocene-age and susceptible to surface contamination
Series title Nature Communications Earth & Environment
DOI 10.1038/s43247-022-00473-y
Volume 2
Year Published 2022
Language English
Publisher Springer Nature
Contributing office(s) California Water Science Center, Colorado Water Science Center
Description 153, 9 p.
Country United States
Google Analytic Metrics Metrics page
Additional publication details