With the West in an extended drought, the Colorado River is more stressed than ever. Rights to the water were divvied up decades ago - on the basis of what were later determined to be historically high flows. Between dams on the river blocking natural seasonal flows, diversions for agriculture, power, drinking water and other uses, it has been a long, long time since the Colorado's water actually reached the Gulf of California.
Till now. Maybe.
More below the Orange Omnilepticon.
New Scientist has a report by Hal Hodson on an unprecedented international agreement to release a pulse of water to try to bring the Colorado River delta back to life.
When the gates of the Morelos [Dam] open on 23 March, the river will be reunited with its delta. The eight-week-long pulse will release enough water into the dry riverbed to fill an area the size of a Manhattan city block with a column six kilometres high.This is intended to restore natural vegetation and animal life to a water course that has been dry for decades. It once supported a thriving biological community and was an important stop for migrating birds. An updated report from Hodson details the massive science experiment even now taking place.
After that, the agreement stipulates that a small continuous flow, totalling an additional 64 billion litres, will infuse the delta over the next three years. It's a trickle compared with what used to reach the delta, but researchers still expect the water to bring around 950 hectares of the delta to life in the weeks after the pulse.
The experiment isn't just remarkable for its scale. It is also the first time water has crossed the US-Mexico border for environmental purposes – the result of years of negotiations between Mexican and US water authorities, as well as a host of NGOs. "As far as I know there has never been an agreement to deliver water for biological purposes," says Michael Cohen of the Pacific Institute in Oakland, California. "It's been in the works for arguably 20 years."
In key areas along the river's last 70 miles to the Gulf of California a huge team of scientists, Rivas among them, has worked for the last year, clearing a path for the river to come. They ripped out salt cedar trees across large meanders in the river's course, clearing them for the seeds of cottonwood and willow that will germinate in the newly wet soil. And now that water is flowing, the team are watching eagerly as the delta springs back to life.Cindy Carcamo of the LA Times also has covered the story. (Slide show of photos here.) The LA Times is a bit less sanguine about how extensive the effects of the water release will be.
"The US Geological Survey will start monitoring surface and groundwater immediately," says team leader Karl Flessa as he watches water rush through the dam. The agreement that set the water in motion, called Minute 319, calls for a small amount of water to continue to flow for three years after the initial deluge, and the researchers will monitor the river throughout.
The focus will be on measuring how the water flows over the dry river bed for the first few days and weeks, as well as changes in salinity, temperature and groundwater recharge. Banks of sensors placed along the riverbed, and driven deep into its soil, will do all of this automatically.
Experts from both countries will study the effects of the release. It's unlikely the water will reach the Gulf of California and unclear whether it will all soak into the soil or be left standing in parts of the channel...This Youtube video shows the river at the Moreles Dam, before the release:
…The pulse is supposed to mimic a flood produced by a spring snowmelt. However, this week's flood will provide only a smidgen of what would have flowed before the dams were built, officials said.
It is the only release planned so far. At the end of the 5-year pilot project, U.S. and Mexican officials will review findings and discuss whether other discharges should be made.
For those who've seen images of the raging Colorado River in the depths of the Grand Canyon, its fizzling out before it can even reach the sea is difficult to comprehend. The 2012 video below gives a ground level view of what the delta has been reduced to, with all of the diversions upstream.
Drought in the West is having serious consequences as water levels drop in rivers and lakes. NBC News had this story on a massive salmon transfer by truck, because there's not enough water in the river to release them at the hatchery.
The difficulties and protracted negotiations to restore even a limited amount of flow to the Colorado is important in many ways. It's a critical experiment in restoring a devastated ecosystem with importance far beyond its immediate locale. It's practice for addressing an increasingly serious problem around the world, as growing populations place ever greater demands on limited water supplies. It's urgent because Global Climate Change is disrupting what were 'normal' patterns in the water cycle: too much water in some places, not enough elsewhere.
As goes the Colorado, so goes the rest of the world's rivers?
8:26 PM PT: UPDATE: thanks to Bob Love for a link to what it looks like now with the water flowing.