Water managers and state wildlife officials last year hoped the discovery of a microscopic zebra mussel larva in the Colorado River was a one-time event, not a sign of a larger problem lurking beneath the surface. It was the first time larvae from the destructive invasive species had been found in the river in Colorado. For nearly a year, despite increased sampling, state wildlife officials didn’t see any more evidence of the mussels. But their hopes were dashed earlier this month when Colorado Parks and Wildlife detected three more tiny larvae in the stretch of the Colorado River between Glenwood Springs and Silt. The mussels — known to devastate ecosystems and clog critical infrastructure — had once again found their way to the river that is the backbone of Colorado and the Southwest’s water supply.

Other Colorado River Basin news:

• Steamboat Pilot & Today (Colo.): North American Monsoon is on its way to Colorado. Whether it will be a typical monsoon season is yet to be determined
• NASA Earth Observatory: Blog: Arizona’s declining groundwater
• The Land Desk: Blog: Would a Colorado River deal spell disaster for the Grand Canyon?
• Arizona Republic (Phoenix): Video: Colorado water managers discuss ‘fascinating and terrifying’ challenges
• Arizona Republic (Phoenix): Photos: Experts measure the Colorado snow that feeds the Colorado River