Groundwater is an important alternative to surface water. Sadly, this was not fully recognised until late in the 20th century when population pressures, variable rainfalls and increasing polluted water sources forced a search for alternatives. Groundwater, the forgotten, hidden resource attracted great scientific and geographical interest.
Few realise that groundwater supports surface water such as rivers, lakes and wetlands. In many ways, no groundwater means no reliable storage and supply of quality (unpolluted) water for agriculture, industry and domestic use. Until the late 20th century, few realised how inadvertently we rely on quality groundwater.
To mainly dry countries such as Africa, groundwater is a necessary water source. Villages are sited near groundwater supplies avoiding the cost of long distance pipes to carry the water. The monetary expense of establishing reservoirs is avoided and the loss of precious water to evaporation is reduced if not avoided completely.
To some “cold” countries such as Denmark and Iceland, it is more cost effective to tap into groundwater than to use surface reservoirs. Groundwater is easily accessible, constant (not iced) and of high quality.
British Columbia in Canada is facing, like most countries, a growing population. With most surface water supplies allocated to public and private use, more and more there is a demand for groundwater to meet the population increase. Currently, groundwater meets 25% of water needs in British Columbia and, on a national level, meets 26% of Canada’s water needs, but those figures are expected to increase in the near future.
Groundwater seepage into river beds is important to plant and wild life dependent on the river. It is a vital means of maintaining rivers and wetlands in times of low rainfall. The majority of the UK’s rivers and streams are maintained by groundwater.
One particular advantage of a groundwater supply is that this water retains a constant temperature. It may be used for cooling houses in summer and as “heat pumps” to warm houses in winter. If other heating/cooling sources diminish, perhaps groundwater may assume a more important role in this area? It seems possible.
So far, groundwater appears to be a perfect answer to any surface water shortages. But there is a growing problem highlighted by a number of reports from the UK, forcing the government Groundwater Regulation of 1998. Nitrates used mainly in agriculture are seeping into the groundwater. There is a sense of urgency to find means of controlling this trend because once the groundwater is contaminated, so the slow movement of this groundwater will ensure porous rocks (aquifers), plants, wetlands and river systems are contaminated. The results could be catastrophic and deadly.
A large number of websites from many countries are devoted to groundwater reports and attempt to advise on surface activities. So many websites world-wide suggest that public controls must be established to protect groundwater supplies.
In my country of Australia, there is a National Centre for Groundwater Research and Training which initiated a project in January 2008 to collect data on groundwater and to detail management strategies in Australia. The project is not due for completion till 2013. Clearly, it is a mammoth, important task. (N.B. In comparison with the Canadian figures, groundwater represents 30% of Australia’s water supply.)
Groundwater represents 70% of the world’s freshwater. In Europe already, 50% of the wetlands are critical because associated groundwater has been over-exploited. Europe acts as a warning to other countries that it is vital for our future to value, manage and regulate groundwater very, very carefully.
Why is groundwater important? As we need more uncontaminated, reliable water just to survive, we may realise that groundwater could well be the only answer. If only we understood a long time ago.
The Groundwater Foundation – http://www.groundwater.org/gi/whatisgw.html
“NOVA Science in the News” published by Australian Academy of Science http://www.science.org.au/nova/100/100key.htm
Groundwater Basics – http://www.groundwateruk.org/html/basics/basics2.htm
Canada and British Columbia references -http://www.tol.bc.ca/index.php?option=com_content&task=view&id=1063&Itemid=900