The lens of freshwater in a tropical island: the two interface case

Abstract

The lens of freshwater beneath a tropical island is vital for supplying water to the island population. We consider the circumstances under which artificial recharge through a single inlet point will maintain the lens if no natural recharge occurs. A Greens function approach derives an integral equation that is solved numerically for the case in which two interfaces exist---one between salt and freshwater and one between freshwater and air. There appear to be upper and lower bounds on the flow rates that produce steady interface shapes. The height of the seepage faces is dominated by the density ratios. References

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