Groundwater depletion could cause land subsidence
Usage in the UAE is 20 times higher than the natural recharge rate, expert says.
Groundwater in the UAE will be depleted within half a century, potentially causing subsidence affecting buildings and roads, if current net water consumption levels are maintained, according to an expert.
Dr Peter Werner, director of the National Water Center, UAE told delegates at the Saint Gobain 350 conference in Abu Dhabi:
“Groundwater usage [in the UAE] is 20 times higher than the natural recharge rate. This has to change. Water is being consumed, but not reused.”
Nearly two-thirds of water consumed in the UAE comes from groundwater, compared with 29% from desalination plants and 6% from water recycling.
“We are seeing a significant depletion of groundwater aquifers. Based on current water consumption levels, groundwater in the UAE will be depleted 50 years from now.”
He warned: “That will cause land subsidence, which could have a big impact on construction and roads.”
Werner said subsidence was a general, rather than a specific, risk of groundwater depletion, depending on soil types. But he pointed to groundwater-related subsidence in Frankfurt, Germany as evidence of the problem. There, groundwater levels were depleted by 50m-60m, leading to land subsidence of up to 2m.
“Fast growing cities tend to build without replenishing their groundwater. There's a focus on short-term profit and nobody sees the long-term view. But I hope that can be prioritised in the Middle East,” said Werner.
“In Europe the political cycles are around 4-years, which encourages short-term thinking. But here, with the ruling families, they can afford to think long-term.”
Werner added: “Sometimes I think water is more important than oil for living conditions. Groundwater is a treasure. Don't use it up. Keep it or recharge it. We need to protect it.”
He said that the solution is artificial groundwater recharge using treated wastewater, which is both environmentally sound and cost effective, if not cheap.