Lismore’s ground water or what can I do with the borehole.: A talk by Noelle Odling 5 February 2022 at 7.30
The story so far:
Foster Yeoman opened the Glensanda super quarry in 1986, and it is now the largest quarry in Europe exporting granite to the world. The site was chosen by John Foster Yeoman when he was sailing by. Perfect for quarrying granite, he must have thought. Miles from anywhere. Although the small sliver of land known as Lismore was probably not uppermost in John Foster Yeoman’s mind, it soon was as they began employing locals in various capacities and, in a place where work is hard to get, locals responded. Likewise as good neighbours, they have always responded to requests for financial support. Mrs Angela Yeoman OBE opened the Heritage Centre in 2007 after they supplied transport for all the materials needed.
They also supplied agricultural waste bins, supported the Community bus and much else. Foster Yeoman sold the company to Aggregate Industries in 2006 but support has continued. And many of us have been invited to visit and tour including the schoolchildren. I know this is all PR, but the Yeoman family were genuinely interested in Lismore.
But it was the boreholes that added to the quality of Lismore life as water is the number one problem; either we have too much or too little or the pipes fur with the limestone and white goods hate limey water, etc. So in July 2012 a very large machine supplied by Yeoman Glensanda began drilling boreholes in the hope of finding water to supplement the springs which most islanders rely on and which do (for some on a reasonably regular basis) dry up.
Not all drilling found water and not all householders were able to take advantage of the machine as its sheer size and weight meant it couldn’t go far off-road, turn sharp corners without ripping up the road, or go on unsealed roads. Nevertheless, about 35 households benefited, and many now have an additional water supply. Foster Yeoman had earlier in the nineties supplied boreholes but with a less gigantic machine.
Noelle’s talk::
Everyone on Lismore has a private water supply mostly from a well situated on a reliable spring. Many people on the island had water supply problems towards the end of the summer of 2021 and many others were very conservative in the use of water because of concerns over their water supply.
Noelle started with some basic groundwater principles and described Lismore’s groundwater system whichhas a limestone aquifer that owes its permeability to the many fractures it contains and also to the dissolution of limestone by rainwater which enlarges the fractures. She presented the results of borehole testing carried out in 2013-14 as they showed a wide range of hydraulic conductivity (a measure of the ability of the rock to allow the flow of water) over some 4 orders of magnitude. Comparing the results with the performance of one borehole already exploited, indicatde that most of the tested boreholes could be expected to give a reasonable domestic water supply. She discuassed the pros and cons of a borehole on Lismore for a domestic water supply. For the entire informative text Read here
The history of boreholes on the island is here
This talk was repeated at the Heritage on 16 April 2022 at 7pm

