History in water flowing through the Burren

16.12.2021

FRESH water is vital for life, and our position in the solar system means that our planet has plenty of the good stuff. Fresh water has played a huge role in the development of the geological history of the Burren; from the rivers that once flowed into long-gone seas more than 300 million years ago to make the rocks of the Cliffs of Moher, to the massive frozen sheets of ice that carved the valleys in the Burren just a mere 20,000 years ago.

All the water on Earth is constantly being recycled, the same water that the fossil corals were living in 330 million years ago is a tiny part of the water we drink every day. This is important, as there is no new source for water on Earth, so we really do need to look after it. As we all know, most of the water that falls on the Burren comes from clouds that develop over the Atlantic Ocean which are pushed here by southwesterly winds. That water was very recently salty seawater, but the process of evaporation extracts the fresh water and it ends up falling on us and the rocks of the Burren. For the most part, this rainfall ends up flowing down the cracks in the limestone and disappearing underground and surface water is very scarce here.

The Caher River and the Aille River are the exceptions to this, they can maintain flow all year long from source to the sea. Climate change models predict changes in rainfall over the coming decades for the west of Ireland and this will impact on these two rivers and may lead to an increased risk of flooding. ‘For the most part, this rainfall ends up flowing down the cracks in the limestone and disappearing underground and surface water is very scarce here.’

We have recently started a project to look at this in more detail; the Aille Engaged project is a community citizen science project between the Geopark, Earth and Ocean Sciences, NUIG and the Lisdoonvarna Historical Society with financial support from Geological Survey Ireland.

The citizen scientists collect daily rainfall and river level data for the Aille River catchment and input that data directly onto our website where it is displayed. The Aille River is a complex river system that has two distinct sources that combine at the Spa Wells in Lisdoonvarna.

From the north we get the rain that falls over Slieve Elva and Poulacapple; most of this water enters limestone cave systems, emerges at Killeany spring, decides to go underground for a while again and then finally becomes the Gowlaun River just outside Lisdoonvarna town. The other branch, the Aille River, spends all its time as an overground river flowing over shale.

Ultimately, the combined waters flow all the way to the sea at Doolin, well almost; when not in flood, the river decides to go back into the limestone again just before entering the sea, mirroring its initial descent into the underground on the slope of Slieve Elva. Figuring out exactly where all the rain that falls in the Burren ends up may take some time.

Dr. Eamon Doyle, geologist – Burren and Cliffs of Moher UNESCO Global Geopark, Clare County Council.