100 Places To Remember: Perth, Australia
Geschreven op 2-3-2010 - Erik van Erne. Geplaatst in Natuur
Green Metropolis on the Edge of the Desert. The city of Perth in south-western Australia is one of the most isolated metropolises in the world, with the nearest large city more than 2,000 kilometres away.
Although Perth sits at the edge of a vast desert and has one of the driest climates in the world, it is renowned for its luxuriant European-style parks and gardens, lush green lawns and open spaces.
Such opulent greenery is possible thanks to a geological peculiarity of the area. Perth is situated above a vast aquifer of 40,000-year-old water, which is its main source of drinking water. The only Australian city dependent on groundwater, Perth uses more water per capita than any other city in the country.
Over time, the aquifer has been supplemented with surface water stored in reservoirs. Perths population of 1.7 million is more than double what it was 30 years ago and per capita water consumption has gone up by more than 20%, putting severe pressure on its water reserves. In the same period, the city has seen a dramatic decline in rainfall due to global warming, and this has reduced the surface flow into water reservoirs by 65%, putting further pressure on the non-renewable aquifer source.
Perths famous parks and green areas have not suffered during this process, and about 50% of all fresh water consumed in Perth is now used in its parks and gardens.
During the next 40 years, the temperature in the area is projected to rise by up to 2.7°C due to global warming, speeding up evaporation from soil and plants. In the same period, rainfall is expected to decrease by up to 40%, while the population will continue to grow by 3% a year. These new parameters will demand a radical new attitude to water consumption in Perth.
A wind-powered desalination plant for turning seawater into fresh water opened in 2007 and now provides 17% of Perths water needs. It is nowhere near enough, of course, and unless drastic changes are made the city could face severe shortages of fresh water.
