American Whitewater’s database of whitewater accidents and fatalities, maintained since 1972, documents that 10 percent of river fatalities nationwide are a result of individuals getting caught in a low head dam hydraulic.
These dams are generally defined as man-made structures, up to 25 feet in height, built across a river or stream channel from bank to bank. Powerful hydraulics and hard-to-see horizon lines create a dangerous hazard. Most paddlers have had a run-in with a low head dam in some capacity, whether it is a nasty surf, a tough portage, or worse.
American Whitewater has been working at the local, state and federal levels to address this public safety issue. Understanding the location, utility, public safety hazard, and ownership of these structures can not only better inform recreationists, but also help to better identify structures for removal or retrofit.
In Colorado, local watershed groups, agricultural and municipal water users and other stakeholders have been coming together to develop stream management plans that identify projects that benefit the environment and recreation at the direction of the state water plan.
Low head dam projects have been identified by many of these groups as viable and multi-beneficial.
Retrofit projects can improve diversion maintenance and efficiency while mitigating boat and fish passage issues. Removal of obsolete structures provides huge benefits to stream connectivity. AW continues to work with these communities to identify and implement ripe projects.
In 2019, Colorado’s Department of Natural Resources invited American Whitewater to be on a steering committee about a low head dam safety initiative. The state initiated the project by doing a Google Earth-based inventory of all low head dam structures in the state. Once the inventory was published, an awareness campaign was launched that coincided with the runoff and summer season to help recreators be prepared for the low head dam hazards.
AW was happy to join the state in the campaign and to talk about utilizing the recently completed inventory to identify and prioritize projects. This effort is in the final phase. When complete, we will have an easily comparable scoring metric to quantify the benefits of retrofit or removal of a low head dams to safety, recreation, aquatic habitat, and watershed connectivity. This will be a tool to identify viable projects for implementation.
The importance and utility of understanding the exact location of low head dam structures became very clear through this work in Colorado. Our partners at the Theodore Roosevelt Conservation Partnership were aware of the state work American Whitewater was doing and asked if we would be interested in pursuing a national effort to address issues with low head dams. With partners in the recreation community, we developed a proposal for a low head dam inventory and technical assistance program to be administered by the Army Corps of Engineers to address both public safety issues and ecological issues with low head dams.
As a result of that work, in early May the Senate Committee on Environment and Public Works unanimously advanced its 2022 Water Resource Development Act, including a directive to the US Army Corps of Engineers to develop an inventory of low head dams. American Whitewater reached out to our membership to help in asking the House Transportation and Infrastructure Committee to also include the initiative.
A couple of weeks later they heeded your calls and included a low head dam inventory as well. We now have bipartisan and bicameral support for this program.
As we await the conclusion from Congress, we are excited to continue to learn and advocate
for mitigating the hazard low head dam structures around the country.
Over the past two centuries, tens of thousands of low-head dams were constructed across rivers and streams nationwide to provide services such as diverting water for irrigation or providing municipal and industrial water.
American Whitewater is working hard to reduce the safety concerns created by these structures while ensuring that the important utility some of them provide is maintained.
By Hattie Johnson, Southern Rockies stewardship director for American Whitewater