Marble Arch Caves: the science behind the tracing of water
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'Alien green' dye shows science behind the tracing of water in Fermanagh

A harmless dye makes the Shruh Croppa river in County Fermanagh take on an other-worldly look.

The green dye lets hydrogeologists trace the flow so they can predict the water's effects above and below ground.

  • 11 Mar 2018