- Water releases to be reduced September 16 for nine hours.
- Lower flows will expose caddisfly pupae and larvae.
- Experiment supports Bullhead City and Laughlin abatement efforts.
Monday, September 1, 2025 — On September 16, 2025, the Bureau of Reclamation
will temporarily reduce water releases from Davis Dam to assist local efforts aimed at reducing caddisflies along the Colorado River. From 5 a.m. to 2 p.m. Mountain Standard Time, releases will be lowered to about 2,300 cubic feet per second.
A caddisfly is a small insect that spends its early life in water, where its larvae build protective cases out of sand, twigs, or other materials. As adults, they look a bit like moths. They are important for healthy streams and are often used to measure water quality. However, in some places, their swarms of adults can be a nuisance. Large numbers may cover lights, buildings, or boats near water.
Reclamation’s special operation is designed to expose the caddisfly pupae and larvae clinging to the riverbanks. Once exposed, they are more vulnerable to drying and to natural predators such as birds and bats.
Safety Advisory for River Users.
During the nine-hour reduction, water levels below Davis Dam will drop noticeably. Reclamation cautioned that boaters and others using the river may encounter new hazards. Sandbars, unstable banks, floating debris, and submerged objects may appear or shift until the river returns to its normal flow schedule.
Local Communities Seek Relief.
The experiment is being conducted at the request of Bullhead City, Arizona, and Laughlin, Nevada, as part of an ongoing caddisfly abatement study. The insects are considered a nuisance by local residents and businesses, particularly those catering to visitors.
According to Reclamation, the decision to carry out these operations followed input from scientists, federal dam operators, and community representatives. The study is designed to provide maximum benefit to Colorado River communities while also considering the need for reliable water deliveries, hydropower generation, and recreation.
Operations May Change.
Planned releases could change depending on environmental or operational conditions. Reclamation continues to publish daily and hourly release information for Colorado River dams, along with projected schedules for both Davis Dam and Parker Dam.
Image:
Davis Dam (Bureau of Reclamation).
