Power restored to Mercer Island High School After a brief power outage this morning near Mercer Island High School, which disrupted some early classes, the power was restored around 8:30 a.m. According to the MISD website, normal operations resumed at 9 a.m. By Reporter Staff • May 21, 2012 11:56 am After a brief power outage this morning near Mercer Island High School, which disrupted some early classes, the power was restored around 8:30 a.m. According to the MISD website, normal operations resumed at 9 a.m.