A possible discharge of water from an old mine site upstream from Left Hand Creek in Boulder County killed an unknown number of fish.
Energy and Environment
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Broomfield residents say the city isn't following guidelines set by a new law to prioritize health and safety over oil drilling.
Cranbeary leaves Tuesday for new digs in Alaska. She and Lee were together for seven years and were unable to produce a cub.
Professor Zoe Donaldson studies how humans grieve the loss of romantic, monogamous partners by researching the tiny rodents.
A new study from the National Center for Atmospheric Research in Boulder predicts more rainfall on fewer, concentrated days leading to more intense flooding.
Justices heard oral arguments in the high-stakes case but did not say when they would rule.
In the United States, Brazil and China, at least two-thirds of the barley grown goes into six-packs, drafts, kegs, cans and bottles.
Environmentalists are challenging a court ruling over whether water from the river is properly accounted for and being used in beneficial ways along the Middle Rio Grande Valley.
Another native Colorado fish population has been returned to healthy levels.
A United Nations report out this week said the world is due for "rapid and far-reaching" changes by 2030 because of global warming.
It's not over yet, too: The long-term effects of drought go on long after the dry weather ends, and the impact of the new USMCA is to be seen.
The long-waited announcement comes as the river's two largest reservoirs, Lake Mead and Lake Powell, have been drained to alarmingly low levels.
Westmoreland Coal Co. has more than $1.4 billion in debt amid declining demand for the fuel.
When you drive into Ouray County, a sign reads “Welcome to Ouray County: A Right to Farm County.” But what do these laws ensure farmers?
Thousands Of Migrants Have Died Crossing The Border. Human Rights Groups Want The FBI's Help Finding Their Remains
Advocacy groups gathered in Boulder to appeal for access to an FBI-run DNA database to help locate and identify migrant remains.