In an attempt to protect property from historical flooding, a private developer constructed flood control facilities on a plain to divert canyon floodwaters northwest into a nearby channel. When a severe tropical storm occurred in the region, the floods caused by the storm overtopped the dike and levee at the point where the facilities were designed to divert the floodwaters, causing about $20 million in damage. Rains from the storm led to the flooding of the Plaintiffs’ apartment building, which was inundated with water, mud, and debris flowing from the point of the breach in the flood control facilities in a concentrated manner and at an abnormally rapid rate of flow. A wall along the southerly property line collapsed, and mud and debris buried automobiles parked on and adjacent to the property. In view of the damage caused by the storm, the United States Army Corps of Engineers agreed to participate in constructing flood control improvements. Their design, approval, and installation took nearly eight years to complete and cost the District about $7 million. Plaintiffs filed an inverse condemnation action against the District, seeking compensation for its physical invasion and destruction of their property.