Dónal Hickey: Taking water for granted
In the coming years, we’re likely to be hearing a lot more about ‘rainwater harvesting’ which is common in places such as Australia and parts of America but something we haven’t really got to grips with here yet.
The term is all about saving the water that runs off roofs and hard surfaces, most of which, literally, goes down the drain. At the same time, we use expensively treated water in gardens, to flush toilets and wash cars. Toilets alone can account for a third of all domestic usage.
In the harvesting process, water from gutters and paved areas is routed to underground storage tanks. Leaves and dirt are removed by filter and cooler conditions underground help prevent, or at least reduce, bacterial contamination.
But all of this is not really new. Our ancestors were into saving rainwater, especially in days before piped water became common. People of a certain vintage will remember barrels at the gables of house to catch water from roofs while farmers often had large, concrete troughs in which to store rain water flowing off sheds and other buildings.
For people interested, a trawl through google will show that several companies in Ireland are providing water harvesting technology and installing tanks for commercial, agricultural and domestic use.
Because we get so much rain, we tend to take water for granted and use it in a cavalier way. Irish Water is trying to deal with a huge 43% leakage rate from pipes in public schemes and is hoping to get leakage down to 38% by 2021. Many schemes are old and have been neglected over many years, leaving us a legacy of problems with wastage and other issues.
Given Australia’s dry climate, it’s only natural that the continent should be an exemplar in water harvesting. I’ve seen suburban homes in Sydney with 5,000-gallon tanks. People have to hold onto every drop and the tanks are therefore seen as essential.
All of which concentrates the mind on how we use water as shortages loom during the summer.
Highlighting the urgency of the present situation, the Water Forum warns that extended dry weather and continued demand will result in lower water levels in rivers and lakes which are the source of public drinking supply for over 80% of the population. And critically, lower water levels mean there is less water to dilute pollutants.
Met Eireann records show we had 37 dry spells (15 consecutive days with less than 1.0mm rain) in the past two months. Normally, we only have about 37 dry spells over a year. This has happened at a time when the need for extra hygiene to combat Covid-19 has resulted in 20% increase in demand for water.
