New growth in delta could offset CO2 released from riverbed
Human management of natural ecosystems always has unintended consequences, and the Colorado River is no example. After decades of intense dam building and diversions, the mighty river is a mere shadow of it former self, reduced to a trickle in some places and polluted by return flows in others. Along its entire length, ecosystems, including riparian zones and native fish, have suffered, with some of the biggest impacts in the Colorado River delta.
In an effort to restore at least some key reaches of the river, scientists and water managers have teamed up to try mimic some of the Colorado’s natural functions, with controlled releases of water to build up beaches. Those efforts culminated in early 2014 during an eight-week experiment that unleashed a mighty torrent of water from Morelos dam (on the border with Mexico and the USA).
The huge surge (130 million cubic metres) of water raised river levels down to the delta, which has been starved of water for decades. Scientists closely monitored how the release — and potential future releases — affect agricultural crops and natural plant and animal life of the lower delta.
Many streams are at risk from pharmaceutical pollution
Traces of pain-relieving substances, diabetes drugs and allergy medicines are widespread in small streams across the Southeast, especially in urban zones like Raleigh, North Carolina, the U.S. Geological Survey found in a new study.
New study helps resource managers plan for climate change
Resource managers grappling with the vexing question of how to allocate Colorado River water to the thirsty cities, ranches and farms of the Southwest have some new food for thought. A new U.S. Geological Survey study published this week in the journal Water Resources Research shows that more than half the streamflow in Upper Colorado River Basin originates as groundwater.
Much of West reports record-fast meltdown under El Niño heat
April storms helped boost Colorado’s statewide snowpack to above average, but two river basins in the southern part of the state continue to report below normal readings.
The state’s mountain areas benefited the most from a series of wet, El Niño-fueled storms, bringing precipitation for the water year to average, according to Brian Domonkos, the Colorado snow survey supervisor for the USDA Natural Resources conservation service.
“At this time last year the water supply outlook was grim at best,” Domonkos said. “Colorado’s current snowpack and precipitation levels are right where we want to be this time of year. Elsewhere in the Western United States seasonal snowpack during 2016 succumbed to early spring warming and did not recover as Colorado did from recent storms,” he added. Continue reading “April storms boost Colorado snowpack”→
City takes big step toward more sustainable water use
Denver, Colorado took a big step toward meeting an ambitious 20 percent water conservation target by passing an ordinance authorizing the use of gray water for residential, commercial and industrial purposes. The city hopes to cut per capita use of potable water by 20 percent by 2020.
Enabling large water users like hotels, multi-family residential complexes and dormitories, as well as industrial facilities, to use gray water will not only help conserve a valuable resource, it will help those facilities save money. Continue reading “Denver authorizes gray water program”→
Using a vast sample of data collected in a citizen science project, researchers say they’ve been able to discern how hydropeaking affects aquatic insects that form the base of river food chains. The information could help resource managers develop alternative hydropower practices that aren’t as harmful to ecosystems, according to a new study published in the journal BioScience.
Hydropeaking refers to the practice of increasing river flows at times of peak demand, generally during the day. This study shows how abrupt water level changes affect aquatic insects in every stage of life. The research was done by scientists with the U.S. Geological Survey, Oregon State University, Utah State University and Idaho State University. Continue reading “Environment: Can dams be operated without killing rivers?”→