as 50–60. US$11 million (equivalent to $ million in ) in damage was caused. The quake was felt outside the region. In Salt Lake County, Utah, police officers at the local jail and officials at the Salt Lake Municipal Airport felt the effects of the earthquake. Water levels in wells were affected as far away as Hawaii, away, where water in wells fluctuated , and in Puerto Rico. Levels in nearby Idaho fluctuated as much as . Earthquake Lake The landslide caused by the quake blocked the flow of the Madison River. The blockage caused the water to rise and formed a new lake, which was later to be named Quake Lake (officially Earthquake Lake). Fearing that the pressure caused by the rising water would result in a catastrophic flood, the Army Corps of Engineers began to cut a wide and deep channel into the slide. By September 10, water began to flow through the channel. To prevent more erosion by the flowing water, the Army Corps cut another channel which was completed on October 29. The construction of the two channels cost US$1.7 million (equivalent to $ million in ). Aftermath Amateur radio operator K7ICM transmitted news of the quake at 11:43 p.m. (MST). At 11:50 p.m., another amateur in Idaho contacted the Idaho State Police who in turn contacted their headquarters in Boise. The Montana Highway Patrol, Montana State Civil Defense and the Montana Department of Fish, Wildlife and Parks also received word of the earthquake and its effects. The geography of the area plus the damage from the earthquake disrupted and/or obstructed radio communications, making broadcasting accurate information about the quake's effects difficult. The Yellowstone County Chapter of the American Red Cross, Salvation Army and various other local, national, and organizations from multiple states sent aid to the victims of the earthquake. The Red Cross also set up temporary housing in Bozeman and the Wyoming Department of Health sent 200 trailers to the Yellowstone area to be used as hospitals. Because the majority of the roads in and around the Yellowstone area were either damaged or blocked by the landslides and the quake, equipment and personnel from the United States Air Force and the U.S. Forest Service were brought in to transport the injured to nearby hospitals outside the quake zone and to perform search and rescue missions in Madison Canyon. 300 people trapped in the canyon