Science Gets Up to Speed on Dry Rivers
https://eos.org/opinions/science-gets-up-to-speed-on-dry-rivers
Source: By Margaret Shanafield, et al, Eos/AGU.
Excerpt: Australia’s third-longest river, the Darling, normally experiences periods of medium to low flow, punctuated by flood events. But vast stretches of the river in New South Wales have been bone dry for the past two summers, and in 2019 the river was dry by early spring. The lack of flows has left communities along its banks in dire straits, with many trucking in water to serve even basic domestic water requirements. Millions of dollars have been spent building pipelines to distant reservoirs, while groundwater resources have also been put under increased stress to fill gaps. River ecosystems have also felt the impacts acutely, with mass fish deaths being just one example. Periods of drought are partly responsible for the diminishing flows in the Darling. More important, however, are increasing water withdrawals over several decades that have taken a toll on this river, whose flow has been heavily altered by damming and diversion for irrigation. The challenges posed by the increasing frequency and duration of no-flow periods in rivers are not unique to arid regions: Over half of the world’s streams and rivers are dry for some part of the year, and the geographic extent of nonperennial waterways is forecast to increase because of climate change and increasing water use. Headwaters in humid regions typically also dry out for part of the year because they drain such small regions. These streams, too, are being affected by climate change....
Source: By Margaret Shanafield, et al, Eos/AGU.
Excerpt: Australia’s third-longest river, the Darling, normally experiences periods of medium to low flow, punctuated by flood events. But vast stretches of the river in New South Wales have been bone dry for the past two summers, and in 2019 the river was dry by early spring. The lack of flows has left communities along its banks in dire straits, with many trucking in water to serve even basic domestic water requirements. Millions of dollars have been spent building pipelines to distant reservoirs, while groundwater resources have also been put under increased stress to fill gaps. River ecosystems have also felt the impacts acutely, with mass fish deaths being just one example. Periods of drought are partly responsible for the diminishing flows in the Darling. More important, however, are increasing water withdrawals over several decades that have taken a toll on this river, whose flow has been heavily altered by damming and diversion for irrigation. The challenges posed by the increasing frequency and duration of no-flow periods in rivers are not unique to arid regions: Over half of the world’s streams and rivers are dry for some part of the year, and the geographic extent of nonperennial waterways is forecast to increase because of climate change and increasing water use. Headwaters in humid regions typically also dry out for part of the year because they drain such small regions. These streams, too, are being affected by climate change....