The Colorado Department of Natural Resources has launched an initiative to increase public safety around low-head dams, which have caused a number of accidents and fatalities on Colorado rivers in recent years.
The effort includes new signage around targeted low-head dam sites, emergency responder education, public outreach and partnerships with private and nonprofit organizations, local municipalities and landowners.
A low-head dam, sometimes known as a weir or check dam, spans a river or stream and is designed to raise or divert the water level upstream. It has a low height, or head, as it rises to the upstream headwater. Its variations include designs that benefit agriculture, recreation and architecture, and prevent stream degradation.
An interactive map and webpage is at https://dnr.colorado.gov/colorado-low-head-dams.
The initiative is meant to increase public safety and awareness around low-head dams across Colorado, said Dan Gibbs, executive director, Colorado Department of Natural Resources, in a news release.
“Colorado has seen an increase in outdoor recreation in recent years, particularly on our rivers and streams, but this also has led to tragic fatalities on some of our low-head dam structures. These fatal accidents are avoidable and are a strong motivation for our Department to increase public outreach and education initiatives,” Gibbs wrote.
Since 1986, 13 fatalities have been associated with low-head dams, including four in recent years, according to DNR.
The average age of those involved with low-head dam incidents are 13 to 30 years old.
DNR and a private ditch company recently installed warning signs at a low-head diversion dam on the South Platte River adjacent to the Jean K. Tool State Wildlife Area. The dam, between Fort Morgan and Brush, is the site of drowning fatalities in 2016 and 2019.
They have been criticized as “drowning machines,” recirculating currents below them can swamp vessels and trap people who go over the dam.
They also can be difficult to detect from upstream because their low height and tranquil upstream pool give little warning of the potential danger beyond the horizon.
“This can limit reaction time and boaters’ ability to exit the river upstream of the dam,” the news release said.
Low-head dams, or check dams, sometimes can be identified by structures on the sides of the river bank.
In the Four Corners area, low-head dams and check dams can be found on the Animas River, Dolores River, San Miguel River, McElmo Creek, Mancos River, La Plata River, San Juan River, Piedra River, Pine River and Rio Grande River, among others.
In response to these boating accidents, the DNR formed the Colorado Low Head Dam Safety Steering Committee to address safety issues around low-head dams.
The team includes the Colorado Water Conservation Board, Division of Water Resources’ Dam Safety Branch, Colorado Parks and Wildlife, Colorado Division of Homeland Security and Emergency Management, Colorado Office of Outdoor Recreation, the Mile High Flood District and Wright Water Engineers.
The steering committee oversaw the inventory study of Colorado low-head dam sites.
The low-head dam webpage on DNR’s website includes an interactive map produced from the inventory study, enabling Coloradans to research and locate low-head dams before embarking on a river trip.
The webpage includes a feedback form for Coloradans to help identify missed features on rivers that could be included on the map.
“American Whitewater has been pleased to partner with DNR on this low-head dam inventory project. Safe enjoyment of our nation’s rivers is central to our mission,” said Hattie Johnson, Southern Rockies Stewardship Director, American Whitewater. “We hope to integrate the data into our web based national whitewater inventory to help river users plan for and avoid these hazards. We are hoping to help crowdsource information to prioritize low-head structures and to find solutions to improve their safety.”