A private ranch in Kremmling wants to experiment with putting phosphorus — a chemical regulated as a pollutant — in a river to potentially improve the fish habitat.
KREMMLING, Colo — A private ranch is seeking Colorado environmental regulators’ permission to inject the Blue River with phosphorus — a chemical regulated as a pollutant — as part of an experiment that could help improve trout habitat at a popular high-country fishing destination.
Kremmling-based Blue Valley Ranch, owned by the billionaire philanthropist Paul Tudor Jones II, proposes beginning the project as soon as next summer on an 8-mile stretch of the river running through its 25,000-acre ranch, which is located on both sides of the river between Green Mountain Reservoir and Colorado River.
The ranch has not yet applied for a state discharge permit, which it will need before beginning the project. In September, the Colorado Basin Roundtable, a 35-member group of water planners, voted to provide Blue Valley Ranch, which did not request a financial contribution, with a letter of support.
This story is powered by COLab, the Colorado News Collaborative. 9NEWS joined this historic collaboration with more than 40 other newsrooms across Colorado to better serve the public.
The ranch sits alongside the lower section of the river. Areas on this stretch that have public access are home to relatively large and abundant trout, earning a “gold medal” status from the state. The experiment may help explain why trout farther upstream above the Green Mountain Reservoir appear undernourished. The ranch expects that adding phosphorus to the river will grow more algae, a building block in the aquatic food-chain supporting fish.
If the project helps the fish, water managers could use a similar one to restore the gold-medal status of a section of the Blue River upstream from the ranch’s property that the state delisted in 2016. The designation is based on the size and abundance of fish in rivers with public access. The rare delisting on the river section, north of Silverthorne, was a blow to residents who saw the designation as a way to attract outdoor tourism to the region.
Scientists warn that adding too much phosphorus could create problems downstream. Excess phosphorus creates cyanobacteria, an algae that can be toxic to humans. Last summer, such algae blooms prompted the state to issue warnings and closures to lakes across the state, from Steamboat Lake, north of Steamboat Springs, to Denver’s Cherry Creek Reservoir.