In Pasadena, the Hahamongna Watershed Park behind Devil's Gate Dam is a hidden gem of a hiking area, filled with trees and plants.
But it's being stripped of its trees, and soon hundreds of trucks will be removing tons of dirt every day.
It's part of a long-delayed project to reduce the flood threat from the Devil's Gate Dam to hundreds of homes and the 110 freeway to the south along the Arroyo Seco Channel.
Locals who have been enjoying the beauty of the park are deeply unhappy.
"These trees are 20 and 30 feet tall. Starting now, the trees, the plants, the birds, the burrowing owls, the lizards, and the frogs, they will just be mowed under," said Shannon O'Sullivan. She grew up close to the park and dam and hikes there daily.