The Colorado River Trail in Rocky Mountain National Park is flooded 0.6 miles from the trailhead.
The Water Supply and Storage Company told the National Park Service the cause was a leak from an old culvert on Grand Ditch in Rocky Mountain National Park.
The trail is not closed, but there is a cautionary sign posted at the trailhead.
Grand Ditch Road is closed off to pedestrians.
Park staff and the Water Supply and Storage Company are trying to reduce the leak and to monitor conditions on the Grand Ditch.