David Nelms, a USGS scientist who has been involved in the project, cautions that it may not be a panacea. As elsewhere, the ground here is layered with both clay and sand. Extraction over the last century has compacted both layers. When water is injected, though, it will ‘pump up’ only the sand. The clay remains compacted. “You will never get that back,” says Nelms. “That’s permanent. But [the project’s] sites are scattered and the geology is different in each one of them, so you should expect different responses in different places.”

Land subsidence may be a complicated problem. But with projects like Swift aimed at tackling it, there may be reason for optimism – not only to fix subsidence, but to mitigate its twin challenge of sea level rise. “In terms of can we do something about sea level in our lifetime, this idea may be the only one we’ve come up with that may buy some time for our region,” Henifin says.

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