A scarp extending for 21 miles parallels the mountain front, and in some places multiple scarps formed. Ground motion, or “ground roll,” caused $15,000,000 in damage to roads and buildings in the Challis and Mackay areas. Boulders tumbled down mountains, and some struck homes around Challis 35 miles north. New springs and craters called “sand boils” erupted in the valley, and about 400 billion gallons of water gushed forth in the largest deluge ever recorded after an earthquake in the United States. Identical earthquakes shook this area in the past, as recently as a few thousand years ago, and more earthquakes along this fault system will continue to pull Borah Peak and Thousand Springs Valley farther apart.