Dams have been designed for river flows that will soon no longer apply, according to new research
Over the past four years, John Matthews has been traveling the world to better understand freshwater and climate change issues. He found that poor planning is creating one of the biggest water-related threats.
“We need to think about managing water in a much more flexible way,” said Matthews, who is director of fresh water and adaptation at Conservation International. “Let’s not just design for a single future; let’s think about multiple possible futures.”
In a paper published this month in the journal PLoS Biology, Matthews and his co-authors argue that investment and management decisions risk exacerbating climate-initiated changes, which could lead to economic catastrophes.
The conventional method of building dams is fundamentally flawed, said Matthews. Looking at the available data, engineers decide on a flow rate that they feel will optimize the infrastructure project. The problem, says Matthews, is that historical data is not a very good guide to the future of freshwater resources — particularly now that extreme water conditions have been exacerbated by a rapidly changing climate.
According to the United Nations, humans will feel the effects of climate change through the water supply. The hydrological cycle — which includes surface and ground sources, glaciers, precipitation, runoff and vaporization — is very sensitive to small climatic shifts. This is a concern not only because water is essential for subsistence, but because it’s also the key to economic development. The way humans are managing water infrastructure and conservation, the authors argue, is only intensifying these issues.