Matilija Dam

Completed in 1948 as [a concrete arch dam](https://en.wikipedia.org/wiki/Matilija_Dam) for water storage and flood control, Matilija silted up almost immediately and is now completely filled with sediment. Safety concerns led to notching of the dam, and modern officials have described the original design as flawed from the outset. Ventura County and partner agencies are [preparing for sediment release](https://matilijadam.venturacounty.gov/about/) by 2030, with complete dam removal to follow.

Ojai, California, United States