Trying to piece together just what had happened, the damage, and what help was needed was like a horror movie about “THE THING,” with the exact nature of the horror emerging through the confusion and hysteria in small clues and fragments.
At CD HQ, Potter realized the possibility of Hebgen Dam’s collapse, bursting, shattering, breaking in the quake. It’s an un-reinforced concrete-core earthfill dam 721 feet long, built in 1913 by the Montana Power Co. to regularize the flow of the Madison for downstream power generation. Its failure would threaten the tourists in the valley, and the sleepy 600 population town of Ennis, 65 miles below the canyon mouth.
Conflicting rumors filled the air—that the dam was destroyed. By 2:00 A. M., the police and Highway Department radio frequencies were zinging with these and other unconfirmed reports leaking in about the plight of the dam and the canyon. In Helena, Potter struggled with a vision of a smaller re-enactment of the Johnstown Flood in Ennis if the dam did, or had, let go.
(Montana Highway Commission)
FIRST PATROL
Montana Highway Patrolman Glen Stevens made the first probe up the Madison Valley after the quake. In response to a request for help from Madison County Sheriff Lloyd Brooks in Virginia City, Stevens and Deputy Sheriff “Dutch” Buhl wheeled down to Ennis, arriving at about 2:30 o’clock. The telephone lines were out. It seemed important to warn people farther up the valley of the danger they were in. Some of the folks had already fled. One ranch family was still in bed. There were three groups of sleeping campers. They didn’t argue or waste time. When Stevens suggested they get out, they just left.
As Stevens and Buhl proceeded up the valley, they radioed in at frequent intervals that everything seemed normal. They reported rock on the road at various intervals from 26-mile hill on south to the place above Hutchins Bridge, where boulders tumbling from a rock cliff made the road impassable. Cabin camp operator Otto Kirby had got his people out, but there were two house trailers parked farther up, near the river. Stevens warned the occupants, and got them started out. They gassed up at Kirby’s ranch. It was cloudy and dark. At 3:15 o’clock Stevens radioed in that the water was muddy but otherwise seemed OK, and that he planned to cross the bridge and drive up along the river on an old road on the south side. Sheriff Brooks tried to discourage them, shouting via radio—“Don’t do it, you crazy bastards, the dam’s broke, and you’ll get killed too. Come back!”
It was this message which, picked up on other radios, and relayed to Helena, sparked CD director Hugh Potter to order the evacuation of Ennis.
With Sheriff Brooks’s warning fresh in mind, Stevens says, “Every turn we got off that bench, I thought we were going to meet swimming water.”