PHOENIX— A developer notified federal regulators today that it has abandoned plans for a 200-foot-tall dam along a remote, biodiverse stretch of the San Francisco River at the Arizona-New Mexico border.

The San Francisco River Pumped Storage Project, proposed within protected areas of two national forests, would have destroyed dozens of miles of river habitat for five federally endangered species. In 2020 conservation groups and business leaders commented on and intervened in Federal Energy Regulatory Commission proceedings to stop the project.

“It’s a good day for the spectacular cradle of biodiversity that is the San Francisco River,” said Taylor McKinnon with the Center for Biological Diversity. “This project faced a hellish legal fight and should’ve never seen the light of day. The San Francisco River needs permanent federal protection.”

The project would have pumped water from a new reservoir on the San Francisco River to a second one atop the adjacent canyon rim, generating electricity and revenue from downhill return flows when electricity prices are higher. It would have industrialized national forest roadless areas, wilderness study areas and river reaches eligible for the National Wild and Scenic Rivers system. Upstream dam flooding and altered downstream flows would have destroyed dozens of miles of river habitat for federally protected narrow-headed and Mexican garter snakes, southwestern willow flycatchers, and fish species such as loach minnows and spikedace.

The same developer, Pumped Hydro Storage, has also shelved plans for the Indian Spring Pumped Storage Project in Maricopa County.

However, in both filings with the commission today, the company doubled down on plans to dam and pump groundwater in a side canyon to the Little Colorado River, just upstream from Grand Canyon National Park — an area of deep cultural importance to the Hopi, Navajo, and other Tribes.

The Big Canyon pumped storage project proposes large-scale groundwater pumping that could deplete Blue Springs, the Little Colorado River’s only source of year-round surface water immediately upstream from Grand Canyon National Park. That part of the river harbors the largest remaining population of endangered humpback chub, whose wellbeing is central to the species’ survival and recovery.

The Center for Biological Diversity has intervened in federal proceedings to protect the fish and stop the project.

“This disastrous plan threatens irreversible damage to the Little Colorado River and fast-tracks the extinction of humpback chub,” said McKinnon. “We won’t rest until this proposal is dead.”