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. We've done kayak trips from the Valley to Long Beach a dozen times in the past 10 years," said poet and writer Lewis MacAdams, founder of Friends of the Los Angeles River.
It doesn't end there. What might seem a minor bureaucratic tweak by the Corps could have a domino effect across the river's 834-square-mile watershed, say worried environmentalists and some federal, state and local officials.
Critics say the draft decision issued by Corps regulators weakens federal water protections for many seasonal streams that feed the river. They say this could translate into more mountain development and more dirty runoff flowing through cities to the Pacific.
"Practically speaking, the March 20 decision would open up a number of tributaries and streams to the argument that the Clean Water Act doesn't apply," said David Beckman, senior attorney at the Natural Resources Defense Council.
But how is the Clean Water Act -- among the strongest federal laws guarding rivers, lakes and streams -- linked to the ability to float a boat down the Los Angeles River?
The answer is cloaked in bureaucracy and court rulings.
A 2006 U.S. Supreme Court decision weakened the power of the Clean Water Act to protect certain seasonal streams. Federal regulators who decide whether a stream is protected by the law must first find the closest navigable waterway. Then they have to decide whether the stream has any effect on that waterway.
If it doesn't, landowners may not be required to obtain certain federal permits before building homes, roads or other projects over those seasonal streams. Their plans, however, would still be subject to local zoning laws and building codes.
In a case involving the Los Angeles River, regulators determined that most of it isn't navigable in the first place. So some streams on the edges of its watershed -- most in the mountains and foothills ringing Los Angeles -- may lose some federal protection, critics say.
The local Corps officials who wrote the March 20 draft decision say they strictly followed guidelines developed after the Supreme Court decision.
"When we looked at the L.A. River, we did not find evidence of navigation" beyond the Pacific Coast Highway bridge in Long Beach, two miles north of the ocean, said Aaron Allen, the regulator who wrote the draft decision.
He stressed that the decision does not weaken any federal laws that protect the water in the river, which is fed in part by reclaimed water from sewage treatment plants. He agreed that seasonal streams far up in the watershed, however, could have less protection.
But in the face of critics' concerns, the Corps has withdrawn the navigable river decision pending further study. The results of that review are expected within days.
Col. Thomas Magness, commander of the Corps office that oversees part of the Southwest, emphasized that the Corps is working with the U.S. Environmental Protection Agency on a final decision.
He promised, "it's going to be something we can all understand and defend." He said it was "purely speculative" to conclude that designating the Los Angeles River as nonnavigable would lead to more lax development standards over streams. "I would not begin to throw in the towel and submit to that conclusion."
Any proposal to fill in or build over streams will still be reviewed on a case-by-case basis "on its own merits," he said.
Yet the Los Angeles River case is attracting interest in Washington and elsewhere in part because it's among the first in the nation after the Supreme Court decision.
"The implications of these decisions could be quite large," said David Smith, chief of wetlands regulation at the EPA southwest region, who has met twice with Corps officials while trying to change their decision.
Los Angeles River defenders such as Rep. Henry A. Waxman (D-Los Angeles) and Nancy Sutley, Mayor Antonio Villaraigosa's top environmental deputy, have written letters to federal officials, criticizing the river ruling.
"If the Corps of Engineers applies a similar approach to other rivers, protections against water pollution that are now taken for granted could be seriously eroded throughout the nation," Waxman wrote in a letter to the EPA. He said the draft decision could undercut Clean Water Act rules governing waste discharges, dredging, oil spill prevention and water quality standards in much of the Los Angeles River basin.
Meanwhile, local river enthusiasts are rushing to collect photos and videos of friends and relatives paddling on the river in canoes and kayaks.