How is rainwater connected to our aquifer system? A group of researchers from the University of Hawaiʻi at Mānoa wanted to trace the origins of groundwater from central to leeward Hawaiʻi Island.
Rainwater composition does not change when it hits the ground. The team was able to look at the unique chemical compositions of the rainwater’s hydrogen and oxygen isotopes to trace the origins of groundwater.
This is important because Hawaiʻi’s main source of fresh water comes from groundwater. Diamond K. Tachera is a graduate student at UH Mānoa and the lead author of this study.
"With the isotopes, we can essentially show the state that there’s groundwater here in this aquifer system that’s coming from two or three aquifer systems away," she said. "If we’re not understanding how all of the waters are connected, we’re not really managing our water resources to the best of our ability."
Tachera hopes to further this study to help resource managers better understand Hawaiʻi’s water supply.
"I hope that in the future, we can reframe how we think about water resources, and essentially our water security. If the state isn’t thinking about how connected these water systems are, there’s a lot of implications for whether pollution could affect neighboring aquifer systems," Tachera said.
"I think that it’s not just the amount of water that we’re pumping, but also the quality of water is important to think about when we’re managing water systems," she added.
