Wyoming's £3.2B pumped-storage project sparks fierce environmental backlash

A controversial £3.2 billion pumped-water storage project near Seminoe Reservoir in Wyoming is facing strong opposition. Critics argue the scheme threatens wildlife, fisheries, and local water supplies while offering questionable energy benefits. The proposal now heads to the state’s Industrial Siting Council for a final decision. The company behind the plan wants to construct a 13,400-acre-foot reservoir in the Bennett Mountains above Seminoe Reservoir. Water would be pumped uphill when electricity is cheap, then released to generate power during peak demand. But opponents claim the system would actually lose more energy than it produces.

Local leaders have raised alarms over the risks to the North Platte River, which supplies Casper’s drinking water, wastewater treatment, and tourism economy. Mayor Ray Pacheco warned that the Miracle Mile trout fishery—one of the region’s most prized angling spots—could be devastated by warmer water releases from the project.

Wildlife agencies also highlight unresolved threats to the Ferris-Seminoe bighorn sheep herd, a key source for restocking populations elsewhere. Some biologists doubt these impacts can be mitigated. Meanwhile, federal regulators at the Federal Energy Regulatory Commission have been accused of downplaying environmental harm and relying on flawed assumptions in their review. The project’s future now rests with Wyoming’s Industrial Siting Council. If approved, it would move forward despite concerns over water quality, wildlife losses, and its net energy efficiency. The decision will determine whether the £3.2 billion scheme proceeds—or is shelved over its environmental and economic drawbacks.