Los Angeles River

Army Corps of Engineers officials announced Wednesday that they would stand by their decision to label the Los Angeles River as not navigable. The ruling sparked criticism from the U.S. Environmental Protection Agency and conservationists, who warned that it would weaken federal Clean Water Act rules protecting the river's 834-acre watershed. Critics said the decision will make it easier to develop large areas of the San Gabriel, Santa Monica and Santa Susana mountains because landowners will not be required to obtain certain federal permits.

A trove of trash was plucked from the Los Angeles River on Saturday morning during the 20th annual river cleanup. An estimated 3,000 volunteers spread out over 14 sites from the San Fernando Valley down to Long Beach. Wearing disposable gloves and armed with trash sacks, the garbage-collectors-for-a-day did their part to purge the river of all manner of trash that ends up in its 52-mile stretch.

Randal Kleiser, director of the film "Grease," descended Sunday into a dark tunnel underneath the Sixth Street Viaduct strewn with garbage and covered in graffiti. On the other end was a downtown section of the Los Angeles River he last visited 31 years ago to film the movie's climatic drag-racing scene. "This is very surreal," Kleiser said, stepping on shards of glass. "It was clean and sparkly when we were here." As he exited the tunnel, Kleiser was struck with a rush of nostalgia.

Cyrus Yazdani is a 24-year-old San Jose State University graduate with a degree in art and a job as a convention planner in Las Vegas. But authorities say Yazdani is also "Buket," one of Los Angeles' most prolific taggers who is featured in several heavily viewed YouTube videos defacing signs and buses. His most popular video -- with nearly 170,000 page views -- shows him clambering behind the Hollywood Freeway sign near Melrose Avenue and tagging the structure as traffic speeds below.

As the Los Angeles River bends into the vast industrial district east of downtown Los Angeles, it looks less like a waterway than a decaying open-air canvas for taggers. This largely hidden channel that runs through two rail yards is what authorities describe as the ultimate proving ground for graffiti vandals vying for visibility and reputation. This is not the graffiti you see in alleyways and storefronts.

Over the years, the Los Angeles River has been redrawn, clad in concrete, tainted with chemicals, invaded by countless Hollywood car chases, dismissed as a glorified storm drain. Now comes the latest slap. The city's river can't even float enough boats to qualify as a full-fledged navigable waterway, according to the Army Corps of Engineers. River advocates are outraged. "They're just wrong. That's the simple version of it.

Five years ago today, thousands of bicycle riders and pedestrians converged at the entrance to the Pasadena Freeway at Glenarm Street and Arroyo Parkway for an extraordinary event: ArroyoFest. Although it seemed improbable, the freeway would be off limits to trucks, autos and motorcycles for four hours so the crowd could ride and walk on the road. In one sense, the bikers were reclaiming what was once theirs.

Over the course of almost 40 years, the Clean Water Act -- which compels landowners to secure permits from the Environmental Protection Agency before dredging or discharging pollutants into "waters of the United States" -- has become the cornerstone of our water-quality law, helping states and local governments make development decisions that keep the country's watersheds healthy.

Spreading across the Southland in an intricate web of highways and byways, Los Angeles is not an easy place to get to know, let alone love. Compared with other urban regions, its size and sprawl can frustrate a newcomer's efforts to grasp the totality of the city. Yet for choreographer Stephan Koplowitz, who relocated here two years ago after living in Brooklyn, N.Y., for 24 years, becoming acquainted with L.A. has been a welcome surprise.

It's a vacant lot now, but Los Angeles officials hope to turn the former brownfield site downtown into a cluster of "green" manufacturing businesses to meet the region's growing demand for solar and wind power and other clean technologies. The proposed CleanTech Manufacturing Center would be established on a city-owned 20-acre parcel in an industrial area near the intersection of 15th Street and Santa Fe Avenue, south of the 10 Freeway and west of the Los Angeles River.