Aquifers, 8% of Earth’s Land Area at Risk of Sinking, Flooding

Graphic by Annabel Driussi for ODP

by Amy Lupica, ODP Staff Writer

A first-of-its-kind study has found that in the next 20 years, 1.6 billion people will be affected by crumbling aquifers. Subsidence, the degradation of aquifers due to over-extraction of water and drought, causes the earth to cave in reducing aquifers’ ability to hold water and puts communities at risk of severe flooding. As conflicts around access to water increase around the world, creeping subsidence threatens to throw coastal communities into chaos.

Why This Matters: More than 10% of the world’s population lives less than 10 meters above sea level. As sea levels rise, aquifers around the globe are collapsing and sinking. 

  • In Jakarta, the land is sinking up to 10 inches per year. 
  • In California’s San Joaquin Valley, the land sunk by 28 feet by 1970.

Gerardo Herrera-García, the lead author of the study, said that this sinking will not only strain water supplies but damage infrastructure and natural resources as well. “It will cause these indirect effects or impacts that, in the long term, can produce either damages to structures or infrastructure, or increase floodable areas in these river basins or coastal areas,” he said. And what’s more: subsidence is uniquely sensitive to climate change. 

No matter the amount of annual rainfall you have, the most important issue is that you have a prolonged drought period,” said Herrera-Garcia. When reservoirs run dry, cities pump more water from aquifers, creating the perfect conditions for subsidence. The western United States is currently in what experts are calling a “forever drought” increasing the risk of subsidence in states like California.

A Technical Guide: Subsidence occurs when a dry aquifer has a particularly high amount of clay. When water is sucked out of the aquifer, the layers of clay collapse on themselves, compacting the land and sinking it into the ground. Refilling an aquifer with water, won’t help much because the compacted clay won’t hold as much water as it once did. Michelle Sneed, a land subsidence specialist at the U.S. Geological Survey and co-author of the study explained, “you’ll get a little bit of expansion in the aquifer system represented as uplift on the land surface. But it’s a tiny amount.”

 

Stopping the Creep: Experts worry that there may be no realistic way to stop creeping subsidence. The only way to prevent aquifers from flooding is to stop over-exploitation of water resources, but as the globe warms and droughts become longer and more common, that’s easier said than done. “Aquifers will be depleted, one way or another. It’s not possible to ask people who are in need of fresh water to stop using groundwater because it causes subsidence,” said Arizona State University geophysicist Manoochehr Shirzaei. So, the bigger picture is: What are the adaptation strategies?” Solutions include elevating buildings and innovative water collection methods, but ultimately, the best way to prevent subsidence a global effort to stop rapid temperature rise and end prolonged droughts.

 

Up Next

“Glacier Blood” Threatens Mountain Ecosystems as High Altitude Temperatures Rise

“Glacier Blood” Threatens Mountain Ecosystems as High Altitude Temperatures Rise

by Amy Lupica, ODP Staff Writer “Glacier blood,” or “watermelon snow,” is sweeping across the Alps, and researchers are eager to survey the snow to figure out what’s responsible for the mysterious phenomenon—the culprit: algal blooms. A new study has found that the same algae that cause dreaded red tide are now blooming en masse on mountains worldwide. […]

Continue Reading 451 words
Biden Administration Moves to Reverse Trump Rollbacks of Clean Water Act

Biden Administration Moves to Reverse Trump Rollbacks of Clean Water Act

One more of the Trump administration’s rollbacks will meet its demise as EPA Administrator Michael Regan and the Biden administration are planning to reinstate protections for many marshes, streams, and wetlands — expanding again the coverage of the Clean Water Act under the “Waters of the U.S.” or “WOTUS” rule. 

Why This Matters: Since the late 1700s, 221 million acres of wetlands have been drained in the U.S. for agricultural use. This development has had severe consequences, including fertilizer and pollution runoff threatening drinking water for millions of people.

Continue Reading 552 words
Study Finds Many Lakes are Losing Oxygen at an Alarming Rate

Study Finds Many Lakes are Losing Oxygen at an Alarming Rate

Oxygen levels in lakes are declining globally according to a new study, and experts say that it could have dangerous implications for the wildlife and humans that rely on freshwater ecosystems.

Why This Matters: Lakes only cover 3% of the earth’s surface, but are some of the most biodiverse ecosystems in the world, providing food and water for millions of people around the globe.

Continue Reading 538 words

Want the planet in your inbox?

Subscribe to the email that top lawmakers, renowned scientists, and thousands of concerned citizens turn to each morning for the latest environmental news and analysis.