ANOTHER LIFE/Michael Viney: On days of very heavy downpours, the hill stream flickers beyond the kitchen window, foaming white water at every rock on the way, and swerves noisily but invisibly beneath the big willow at the gable.
It is precious to us for its own rare sake (a living creature of a sort) and for the sight of a dipper under the bridge; it also fills our kettles, cups and veins unstintingly.
Quite when it lost its innocence is hard to say. Back in the 1970s, it was part of the romance that brought us west: a sparkling brook, replenished from the cleanest ocean rain in Europe. Making a little dam with rocks and fixing the pipe for a gravity feed were a pioneering pleasure and part of getting back to nature. Today the dam and pipe are still in place, but the water is waylaid in a tin box on the wall of the house. Here it is filtered through a steel mesh and zapped with ultra-violet light, and at the sink a special feed squeezes it through a ceramic filter. The final result is crystal-clear and guaranteed free of E-coli, but I drink it with rather less joy.
There were "always" sheep on the hill and people living below who drank the water; perhaps the bugs were different, or people's guts were tougher.
The biggest change has been in vegetation - or lack of it - so that the rain rushes off with its cargo of sheep-currants. Too many days with runs of my own, and the cost of a high-tech solution began to seem a sound investment. Similar concerns throughout the west prompt part of Ireland's amazing consumption of bottled water - more than 100 million litres in a year.
High-tech changes have also arrived at the other end, so to speak. Our own septic tank is of the old-fashioned sort, a bit smelly sometimes in summer but percolating away through deep pits of stones and finally nourishing a lovely golden willow near the fence. There's nothing wrong with such conventional systems, which use the soil and subsoil and their natural organisms to "treat" human waste, so long as the ground conditions - the hydrogeology - are right. In many counties, Ireland's glacial lowland subsoils make ideal filters.
Mayo, however, is now one of the counties where the engineers feel the need for something more "advanced". Friends who built a new house up the road were required to instal Puraflo, the twin-tank system developed by Bord na Móna, which pumps the waste through peat-fibre filters. The peat holds microorganisms, worms and insects that work on the waste to produce a final water free of pathogens and coliforms, and with very low Biological Oxygen Demand. A little light on top comes on if it's not working properly.
At some 4,000 it's not cheap - indeed, there's a rural myth that the same tank is being smuggled covertly from one new house to another. And many engineers and environmental health officers completely mistrust the use of advanced systems, regarding them as too complicated for routine domestic use and too easily used as a means of getting planning permission for one-off houses in "undesirable" areas. But any system that promises a blanket independence from local soil conditions and hydrogeology is bound to seem a godsent solution to hard-pressed county planners.
They already have the help of an Environmental Protection Agency manual and national guidelines for groundwater protection. But reliable advice on local geology and soil conditions can be hard to come by. The Geological Survey of Ireland (GSI) has been especially worried about groundwater pollution in "karstic" limestone areas of the west where thin soils above fractured rock can let pollution from septic tanks or cattle slurry seep rapidly into aquifers of underground water and thus the local wells.
GSI surveys have mapped the most vulnerable limestone areas. But lack of staff and resources have led to suspension of the wider Groundwater Protection Scheme, leaving 11 counties still unmapped. In a paper at a recent conference of Irish hydrogeologists, the director of Friends of the Irish Environment, Tony Lowes, revealed economies that have halved the staff available to assess the vulnerability of aquifers mapped for the EU's new watershed directive.
Today's rural housing, as he said, "often seems to be a ribbon development of four- to five-bedroom 'McMansions' with two garages, three 'en suites', modern kitchens, sink waste disposal systems, utility rooms, washing machines, dishwashers, power washers for cars and even Canadian-style hot tubs containing gallons of chemically treated water". The old trickles of effluent are now waterfalls.
In his recent book Dying for Water (Veritas), Fr Seán McDonagh set Ireland's widespread pollution of groundwater into the global crisis of shortage and abuse. He reminded us that while river water may be renewed in 20 days, the recycling period for subterranean groundwater averages 1,400 years. The total number of our wells is something more than 200,000 and, already, probably one-third are contaminated. In a sensible world, we should see all of them as holy.