Researchers revealed the four states that together make up the Upper Basin — Colorado, New Mexico, Utah and Wyoming — lost almost twice as much groundwater as the Lower Basin did during an intense drought in the southwestern U.S. between 2020 and 2022. The finding was unexpected and might signal a turning point for the region, because the Upper Basin has long been seen as more resilient to dry spells than the Lower Basin, said Esther Oyedele, a doctoral student in geosciences at Virginia Tech and the study's first author.
The Lower Basin comprises parts of Nevada, California and Arizona. Less rain and snowfall means the Lower Basin naturally has less groundwater recharge, or less replenishment from other water sources, than the Upper Basin. On top of that, the Lower Basin generally has higher evaporation rates and substantial water demands, given that roughly 30 million of the 40 million people that depend on the Colorado River for water live in the Lower Basin, Oyedele said.
The results showed that groundwater depletion has been a persistent problem in the Colorado River Basin over the past two decades, but losses accelerated in 2019. The three-year drought that began in 2020 is the principal cause of this, because it shrank the snowpack in the Rocky Mountains, increased evaporation and boosted water demand across the basin, Oyedele said.
It's unclear why the deficit is so much higher in the Upper Basin than in the Lower Basin, but the Upper Basin's proximity to and dependence on the mountains for aquifer recharge probably didn't help, Oyedele said. As snow melts, some of it replenishes groundwater, so a reduction in snowfall between 2020 and 2022 would have affected the Upper Basin particularly badly, she noted.
The Upper Basin includes parts of Colorado, Wyoming, Utah and New Mexico, while the Lower Basin comprises parts of Nevada, California and Arizona. (Image credit: U.S. Geological Survey)
Next, the researchers used advanced statistical methods to explore the relationship between groundwater and surface water in the Colorado River Basin. Due to global warming and the overallocation of the Colorado River's water in a 1922 document, the river's flow is now 35% less than it was on average in the 20th century. Water scarcity in the basin has reached alarming levels, according to the study, and Lake Mead and Lake Powell, the two largest reservoirs in the U.S., dropped to record lows in August.
"This distinction is important because it suggests that groundwater depletion is not simply a direct response to surface-water shortages," she said. "Human water use, particularly sustained groundwater extraction, may also play a significant role."
RELATED STORIESLooking ahead, it's hard to tell if the Upper Basin will continue to lose more groundwater than the Lower Basin and what that would mean for the region, Oyedele said. What seems clear, however, is that the Upper Basin is more vulnerable to drought than experts had thought.
On the management side, Oyedele suggested tackling groundwater and surface water together rather than as two separate resources. Groundwater helps to sustain river flows, and rivers can recharge aquifers — so the two are interconnected. Groundwater often serves as a backup during drought, but it shouldn't be treated as an unlimited reserve, she said.
Hence then, the article about surprising new pattern of groundwater loss may signal a turning point for the colorado river basin was published today ( ) and is available on Live Science ( Middle East ) The editorial team at PressBee has edited and verified it, and it may have been modified, fully republished, or quoted. You can read and follow the updates of this news or article from its original source.
Read More Details
Finally We wish PressBee provided you with enough information of ( Surprising new pattern of groundwater loss may signal a turning point for the Colorado River Basin )
Also on site :
- BTS’ j-hope Joins Forces With Streetwear Legend Nigo for New Nike Sneakers: How to Shop the Drop
- Jasmine Mitchell Says ‘Great British Baking Show’ Editors Left Out One Surprising Moment From Her Season
- Oscar Nuñez, Marlene Forte, Otmara Marrero & Vivian Ruiz To Star In Adrian Cardenas’ Directorial Debut ‘In An Orderly Fashion’