In June 1948, empty trailers in the Alto Trailer Court were shipped to the city of Vanport, Oregon to provide temporary shelter for flood victims. The city west of Portland, Oregon was established in 1942 when housing was constructed for workers at Kaiser shipyards in Vancouver, Washington and Portland. At its peak, Vanport (a portmanteau of “Vancouver” and Portland”) housed 40,000 residents, making it the second largest city in Oregon. Flooding at 4:05 p.m. on May 30, 1948, when a 200-foot section of a berm holding back the Columbia River collapsed, destroyed the city. The city was underwater by nightfall, leaving 17,500 inhabitants homeless. The Alto Trailer Court had also been established for wartime housing. It had about 100 trailers, a store, a large auditorium, a recreational hall, and buildings for toilet, showers, laundry facilities and offices for the Federal Housing Authority and the Alto Civilian Defense Unit. After the war the trailers were gradually abandoned, but there continued to be weekly Alto Improvement Association whist parties, Alto Troop 28 Boy Scout meetings and Alto Volunteer Fire department affairs. In 1951, the US government gave the eight-acre Alto Trailer Court site to the Mill Valley School District.