"In fact, a flash-flood warning took effect last July in the San Gabriel Mountains, the mountains of Riverside and San Bernardino counties, as well as the Antelope, Apple, Coachella and Lucerne valleys. Even downtown LA was drenched with 0.09 inches of rain, which is quite rare. Water damage in Arcadia and other areas like Manhattan Beach are thus to be expected and will require swift action to remedy any potential property damage.Allowing floodwaters to soak your home gives more time for the water to seep into floors and walls, causing serious structural damage. You might have to spend fantastic sums to replace damaged wall and flooring materials. Additionally, floodwater could be considered a cesspool of bacteria that exposes your family to severe health risks. "