FLAGSTAFF, Ariz.—The Federal Energy Regulatory Commission has accepted a preliminary permit application for a 24-story dam spanning the Little Colorado River gorge on the Navajo Nation. The proposed project is located about 6 river miles upstream from the confluence with the Colorado River in Grand Canyon National Park.

The proposed project would flood miles of the Little Colorado River gorge, industrializing lands near the Salt Trail and Sipapu, among the Hopi Tribe’s most sacred cultural sites. It would eliminate miles of flowing river habitat for endangered humpback chub and harm some of the chub’s last best spawning habitat at the confluence with the Colorado River.

“It’s outrageous to even consider industrializing such an important area or damaging such important endangered species habitat,” said Taylor McKinnon, a senior campaigner at the Center for Biological Diversity. “This would inflict profound cultural and biological harm. There will be an enormous effort to stop this dangerous proposal in its tracks.”

The 240-foot-tall dam is part of the Navajo Nation Little Colorado River Pumped Storage Project proposed by Pumped Hydro Storage LLC, a Phoenix-based firm. The project would include a second dam and reservoir on the adjacent canyon rim, power lines, generators and other infrastructure.

The public has until Nov. 22 to comment on, or seek to intervene in, the commission’s proceedings on the plan.