22 October 2015, The Guardian. Perth’s double whammy: as sea levels rise the city itself is sinking. The city’s growing population means a growing demand for water, but as more and more water is drawn out of Perth’s acquifers, the land is slowly subsiding. Growing demand for water in Perth has caused the city to sink at up to 6mm a year and could be responsible for an apparent acceleration in the rate of sea level rise, according to new research released by Curtin University. The study, published in the Journal of Geophysical Research in October, found that the rate of subsidence in Perth increased between 2000 and 2005, at the same time as the Water Corporation of WA increased the amount of water it was drawing from the city’s two main aquifers to meet the demands of a growing population. Will Featherstone, professor of geodesy at Curtin and the lead author of the study, described the effect as “like slowly letting the air out of a balloon”. “If you take the water out of the ground, the overburden of all the rocks above pushes down,” he told Guardian Australia. The city appears to be sinking at a rate of between 2mm and 6mm a year, variable throughout the Perth basin. The greatest change was measured at the seaside suburb of Hillarys, which has a GPS sensor to measure the rate of subsidence and a tidal marker operating side by side. Data for much of the Perth basin is patchy. A sinking city also has ramifications for the measurement of sea levels. A few years ago the rate of sea level rise in Western Australia was reported – not entirely accurately, it turned out – to be three times greater than the global average. Read More here