Offshore submarine freshwater discovery raises hopes for islands worldwide

Twice as much freshwater is stored offshore of Hawai'i Island than was previously thought, according to a University of Hawai'i study with important implications for volcanic islands around the world. An extensive reservoir of freshwater within the submarine southern flank of the Hualālai aquifer has been mapped by UH researchers with the Hawai'i EPSCoR 'Ike Wai project. The groundbreaking findings, published in Science Advances, reveal a novel way in which substantial volumes of freshwater are transported from onshore to offshore submarine aquifers along the coast of Hawai'i Island.

This mechanism may provide alternative renewable resources of freshwater to volcanic islands worldwide. "Their evidence for separate freshwater lenses, stacked one above the other, near the Kona coast of Hawai'i, profoundly improves the prospects for sustainable development on volcanic islands," said UH Mānoa School of Ocean and Earth Science and Technology (SOEST) Dean Brian Taylor.

Through the use of marine controlled-source electromagnetic imaging, the study revealed the onshore-to-offshore movement of freshwater through a multilayer formation of basalts embedded between layers of ash and soil, diverging from previous groundwater models of this area. Conducted as a part of the National Science Foundation-supported 'Ike Wai project, research affiliate faculty Eric Attias led the marine geophysics campaign.

Read the full story from the University of Hawai’i here.