Thousands of volunteers have been cleaning up debris from the Los Angeles River, home to one of the region's most fragile ecosystems. Many residents know the river as a concrete drainage channel, and some hope to restore the once-thriving waterway to its natural state.
It comes as a surprise to many that a meandering river once flowed in and around Los Angeles, a place that is dry for most of the year. In the early days of the city, the Los Angeles River provided water for drinking and irrigation, until additional water was carried in by aqueduct in 1913.
A flood-control project begun in 1938 would dramatically change the river, which is seen today by passers-by as a ribbon of concrete that crisscrosses the city. In the winter rainy season, the channel fills with runoff, and briefly resembles a river after a rainfall.
Parts of the old river are visible, however, in the few sections that have been left in their natural state. At one place beneath a highway overpass, flowing water still makes its way through trees and thickets of shrubs.
Four-hundred schoolchildren came here for the start of a two-day clean up, which will take place at a dozen locations along the river. Volunteers from community organizations and environmental groups also came to help, including Aaron Thomas of the organization Northeast Trees. He and his colleagues plant vegetation in the sections of the river that have not been covered with concrete, where he says visitors still find a thriving wildlife habitat.
"You see willow thickets and sycamore groves down in the river here, and that gives a lot of the animals - the ducks and the reptiles and fish - a pretty healthy habitat to live in, well, relatively healthy, compared to other stretches of the river," he said.
Careless residents threaten to further erode the river's health. Journalist and filmmaker Lewis MacAdams, who founded the group Friends of the Los Angeles River in 1986, shows schoolchildren some of the garbage pulled from the site. The children were getting ready to head down to the riverbank and clean out even more trash. "A bag of Fritos, somebody's jams (pyjamas), and a Coke can. These are all things that everybody buys, and a lot of people throw away," he said.
The rubbish ends up in storm drains beneath the city streets, and is carried to the river and out to the ocean.
Chip English of the non-profit group Tree People says the environment here is delicately balanced, and vegetation is important to keeping it healthy. Trees and other vegetation help the soil retain its water, which prevents excessive runoff in the rainy season. That stabilizes the ground and helps prevent mudslides, keeping the river healthy and residents safe.
"We are doing a lot of tree plantings. Not only do the trees capture water, but when you can open up the concrete, and cut some holes, plant some trees, a lot of that water will soak into the soil," he said.
The group plants trees on school campuses, city streets, and in the mountains, which helps control the runoff that often floods the river in the winter.
Teacher Andrea Johnson is here with her fifth-grade students from Atwater Avenue School, and says this cleanup teaches them two things. First, she says, this river can be a dangerous place for those who come here unsupervised in the rainy season. Several people drown each year after they fall into the channel following storms.
She also stresses the importance of the river as the heart of an ecosystem, which she says teaches a larger lesson about the environment. "We only have one earth, and we are the ones that have to take care of it," she said.
Environmentalist Aaron Thomas, one of the many volunteers with a passion for the river, says this fragile waterway has an important place in the city's history. "The reason the city of Los Angeles was built here was because of this river, and so if you love the city of L.A., you have to love this river and appreciate it, even though it has been concreted in, in sections, and abused and neglected. But that is why we are out here, is that we are trying to reverse that trend and restore it to its natural and beautiful state," he said.
The group Friends of the Los Angeles River conduct monthly riverside walks to help residents understand that the Los Angeles River is more than a concrete channel. Visitors can catch glimpses of a thriving waterway, which again resembles a river in some places.