Although there is little that can be done about many lake breakouts , some have been prevented ( or at least delayed ) by human intervention . The 1980 eruption of Mount St. Helens blocked nearby Castle Creek , forming a lake which geologists feared would produce a sudden lahar . The United States Army Corps of Engineers excavated an outlet channel which prevented the lake from overtopping its new debris dam
1980 eruption of Mount St. Helens
1980 eruption of Mount St. Helens
Lake breakout