Recent heavy rain in the high country north of Durango resulted in discoloration of the Animas River on Thursday near Silverton, according to an alert issued by the Environmental Protection Agency.
The discoloration is not related to work at the Gold King Mine or an interim water-treatment plant, the EPA said in its 11:10 a.m. advisory.
Downstream stakeholders were notified about 10:15 a.m. to warn them and allow them to take appropriate measures if they deem it necessary.
Heavy rain is expected to continue into the weekend. But that rain was expected to turn to snow Thursday above 9,000 feet.
Strong rain can wash mud and debris into waterways, affecting turbidity for short durations.