{"id":935321,"date":"2026-10-20T20:14:13","date_gmt":"2026-10-20T20:14:13","guid":{"rendered":"https:\/\/www.newsbeep.com\/au\/935321\/"},"modified":"2026-10-20T20:14:13","modified_gmt":"2026-10-20T20:14:13","slug":"theres-another-water-crisis-in-the-southwest-and-this-ones-invisible","status":"publish","type":"post","link":"https:\/\/www.newsbeep.com\/au\/935321\/","title":{"rendered":"There\u2019s another water crisis in the Southwest and this one\u2019s invisible"},"content":{"rendered":"

\n The United States\u2019 two largest reservoirs have dropped to unprecedented lows this year<\/a> as drought grips the Southwest, but below the ground there\u2019s another water crisis playing out \u2014 one that\u2019s much less visible, but no less alarming.\n <\/p>\n

\n The amount of groundwater in the Colorado River Basin is declining rapidly, and it\u2019s doing so in unexpected ways, according to a new study<\/a> from scientists at Virginia Tech, published in the journal Water Resources Research.\n <\/p>\n

\n Lake Mead and Lake Powell are the visible faces of the Southwest\u2019s critical water problem, as the Colorado River \u2014 which supplies water to nearly 40 million people \u2014 shrinks due to a combination of climate change and human demand.\n <\/p>\n

\n \u201cHowever, they represent only part of the region\u2019s water resources,\u201d said Esther Oyedele, a study author and a geosciences graduate student at Virginia Tech. \u201cGroundwater is another essential component.\u201d It is a vital alternative source in the Colorado River Basin, especially when surface water in rivers, lakes and reservoirs dries up.\n <\/p>\n

\u26c5 Get CNN Weather in your inbox<\/p>\n

The forecast is just the beginning. We\u2019ll\u202fsend you expert coverage and the stories behind the weather \u2014 so you always know more than just the number. Sign up for the newsletter<\/a><\/p>\n

\n To build a picture of what\u2019s happening to the region\u2019s groundwater, the scientists compared measurements from NASA satellites with estimates of surface water, soil moisture and snow-water storage between 2004 and 2023.\n <\/p>\n

\n They found declines across the basin during those two decades, with losses accelerating after 2019. A severe drought between 2020 and 2022 led to particularly significant falls \u2014 and the researchers found a surprising twist.\n <\/p>\n

\n Historically, groundwater has typically declined more in the Lower Colorado River Basin, which encompasses California, Arizona and Nevada. The Upper Basin, which includes Colorado, New Mexico, Utah and Wyoming, has tended to be more resilient as its groundwater benefits from melting snow coursing down the Rocky Mountains.\n <\/p>\n

\n However, from 2020 to 2022, groundwater in the Upper Basin declined by about 618 cubic feet, nearly twice the rate of the Lower Basin, which fell by an estimated 332 cubic feet.\n <\/p>\n

\n \u201cThe system has hit a turning point: The Upper Basin is now experiencing rapid groundwater losses,\u201d the report authors wrote<\/a>.\n <\/p>\n

\n Surface water and groundwater are linked in a delicate dance: Rain and melting snow seep into the ground and recharge aquifers, meanwhile groundwater can also make its way into rivers and lakes, for example through springs.\n <\/p>\n

\n There are big differences in how these relationships play out between the Upper and Lower Basins, the study found. Snowmelt plays a much more important role in the Upper Basin, which receives more precipitation than the generally hotter, drier Lower Basin. Prolonged drought, higher temperatures and reduced snow appear to be placing the Upper Basin region under additional pressure.\n <\/p>\n

\n The research follows another study published last year, which found that the amount of groundwater pumped out of the Colorado River Basin over the previous two decades was enough to fill Lake Mead<\/a>.\n <\/p>\n

\n It takes thousands of years to refill these aquifers, \u201cand we as humans have more or less been burning through it over the last century,\u201d Jay Famiglietti, an Arizona State University professor who was an author on last year\u2019s study, said at the time.\n <\/p>\n

\n The messages of this paper and the new study \u201chave been that while surface water gets all the policy (and) management attention, groundwater dominates the losses from the entire basin,\u201d Famiglietti told CNN recently.\n <\/p>\n

\n Shrinking groundwater is going to be a problem as Arizona, California and Nevada are being forced to make cuts<\/a> to the water they draw from the Colorado River, Famiglietti said, referring to a new operating plan for the basin published in August.\n <\/p>\n

\n The study does not give details on the total amount of groundwater remaining in the basin, only how it has changed over time. It also doesn\u2019t quantify the exact impact of climate change on the falling water levels compared to other factors at play, including human water demand and groundwater extraction.\n <\/p>\n

\n What the study does show is that \u201cgroundwater storage has experienced substantial and persistent declines,\u201d Oyedele added.\n <\/p>\n

\n \u201cFocusing only on reservoirs could therefore overlook an important part of the region\u2019s overall water challenges,\u201d she said, adding that groundwater should not be seen as an \u201cunlimited reserve.\u201d\n <\/p>\n","protected":false},"excerpt":{"rendered":"The United States\u2019 two largest reservoirs have dropped to unprecedented lows this year as drought grips the Southwest,…\n","protected":false},"author":2,"featured_media":935322,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[22],"tags":[64,63,75,128],"class_list":["post-935321","post","type-post","status-publish","format-standard","has-post-thumbnail","category-environment","tag-au","tag-australia","tag-environment","tag-science"],"_links":{"self":[{"href":"https:\/\/www.newsbeep.com\/au\/wp-json\/wp\/v2\/posts\/935321","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.newsbeep.com\/au\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.newsbeep.com\/au\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/au\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/au\/wp-json\/wp\/v2\/comments?post=935321"}],"version-history":[{"count":0,"href":"https:\/\/www.newsbeep.com\/au\/wp-json\/wp\/v2\/posts\/935321\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/au\/wp-json\/wp\/v2\/media\/935322"}],"wp:attachment":[{"href":"https:\/\/www.newsbeep.com\/au\/wp-json\/wp\/v2\/media?parent=935321"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.newsbeep.com\/au\/wp-json\/wp\/v2\/categories?post=935321"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.newsbeep.com\/au\/wp-json\/wp\/v2\/tags?post=935321"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}