The round, black scar of years-old chewing gum. Uneven cracks from an earthquake or a tree root. Fresh urine, likely human.

This is what you can’t avoid seeing if you walk the sidewalks of downtown Los Angeles. But now there’s a new addition getting etched into the city’s built-up filth: about 4 feet by 3 feet, with slick typography and marketing-room appeal, a patch of sidewalk on Figueroa Street now boasts a message brought to you by your friends at Audi.

The automaker is letting pedestrians know about its new “clean diesel” products with advertisements branded into the downtown dirt and grime.

It’s a clever way to get attention: pressure-wash through the scum of the sidewalk to erase an outlined message into the dirt about clean-burning cars. But, according to city officials, it’s also an explicitly out-of-place form of advertising in a city crowded with a forest of illegal billboards and supergraphics. And this one uses the public right of way, installed without the city’s knowledge or approval.

“There’s no way to get a permit for something like that,” says Tonya Durrell from the Public Affairs Office at the city’s Department of Public Works, the agency in charge of building and maintaining city facilities and infrastructure. Sidewalks are within the public realm and fall under the department’s jurisdiction.

Audi’s aren’t the only ads under your shoes. Lining the sidewalk of a section of Temple Avenue was another stenciled message from American automaker General Motors, advertising its forthcoming 230-miles-per-gallon hybrid electric vehicle. It’s a simple 1-foot-by-2-foot outline of the number 230, branded into every other sidewalk panel. There were more than 30 stenciled images on the sidewalk leading to the county’s criminal courts building, likely pressure-washed into the sidewalk buildup in the middle of the night.

Had those pressure washers been caught, they could have faced misdemeanor charges. Or not, in a city whose elected leaders have proved unable to create policies that thwart these and more pervasive types of illegal advertising.

The Bureau of Street Services takes care of L.A.’s sidewalks, and its Investigation and Enforcement Division deals with violations like abandoned sofas and other illegal dumping and — now — sidewalk advertising. The division contacted ad representatives at Audi and ordered them to cease and desist. No fines were levied, nor charges filed.

“Our first option in all of these types of violations is we want to get compliance. Boom,” says Gary Harris, the division’s chief investigator. “We know that people aren’t always aware of these types of regulations, so we make them aware, and we hope that the activities will not continue.”

While the ads are a clear violation of the city’s code, they don’t exactly cross the line when it comes to the state’s criminal code. “Technically, for vandalism, you have to deface the property,” says LAPD Detective Gus Villanueva. “But there is the issue of advertising on public property. You cannot do that.”

Or maybe you can. Eric Davis is the chief operating officer of the branding and marketing firm National Media Services, which has been imprinting these “reverse graffiti” messages on filthy sidewalks around the country since 2003, including a recent Los Angeles campaign whose product he requested remain unnamed.

“There’s nothing illegal about this. There’s nothing immoral about it,” Davis says. “Nine times out of 10, most people don’t know what to make of it. Because it’s not like we’ve broken any laws and it’s not like we’ve defaced public property. If anything, we’ve improved public property. We’ve cleaned up streets that were normally filthy.”

While it’s true the pressure-washed stencils blast the grime, gum and urine from the sidewalk, the cleaned area is relatively small — and shaped into slogans and corporate logos. “It’s just another way to try to get people’s attention,” says Bradley Stertz, corporate communications manager for Audi of America.

Is this just corporate graffiti, an unwelcome blight on public property? Or is it an acceptable new form of advertising? “It’s sort of like a temporary tattoo,” Stertz insists.

Pressure-cleaned sidewalk ads normally remain legible for three to four weeks, depending on foot traffic, according to Joel Mangrum, who manufactures stencils for pressure-wash ads and is one of National Media Services’ partners. “Eventually it’s going to fade away,” he says. “Real graffiti lasts for years.”

Well, that’s true in much of Los Angeles, which is losing the war on graffiti. But outdoor advertising is also controversial in L.A. because illegal signs and supergraphics have evaded any clear regulatory policies. Various city agencies and commissions have bobbled on how to crack down on a problem spawned in large part by L.A. City Council’s habit of creating one exception after another, severely weakening a supposed ban on new billboards.

As L.A. Weekly has reported in a series of stories on the city’s bitter billboard wars, most members of the L.A. City Council have accepted campaign money from major outdoor advertisers, and the city is now believed to contain some 4,000 illegal billboards. Many of the illegally erected structures that tower over businesses and sidewalks are huge, weighing up to 100,000 pounds, and have never been inspected to determine whether they can withstand an earthquake. Yet the City Council, led by Eric Garcetti, has repeatedly punted on the issue, failing to launch an inspection program that is now overdue by several years.

Amid that decadelong controversy, National Media Services has organized sidewalk branding in a handful of big American cities, including L.A., San Francisco and New York. Davis says the company has never faced fines or criminal charges for this “guerrilla marketing.” He says some cities even allow it if permits are arranged and fees paid.

But here in L.A., no money came into the city for the Audi or the GM ads, or another recent stenciling, for Domino’s Pizza — nobody in City Hall even knew about the ads. Had the advertisers asked permission, the city’s Harris says, they would have faced several hurdles.

“There’s a specific process you’d have to go through to advertise on a public right of way in Los Angeles, and that is already granted to a contractor,” says Harris, referring to the city’s outdoor-advertising contract with CBS/Decaux. “There are bus shelters, newsstands and other furniture pieces on the right of way that they can obtain advertising space on, through the city’s authorized contractor. But other than that, there is no other advertising permitted.”

Eric Richardson, publisher of blogdowntown.com, the first to report the sidewalk-grime etchings, says the negative impact is likely pretty small, but the precedent could be dangerous.

“In a way, it’s hard to get too upset about it. ‘Oh, no, they’re cleaning the sidewalk,’ ” Richardson says. “But at the same time, it is an advertising message, and it is in public space. There has to be some sort of a framework for not letting anyone just go in and do whatever they want.”

In a guerrilla advertising campaign in 2006, city officials in Washington, D.C., fined telecommunications giant Verizon for its sidewalk ads created with spray-on chalk. But only seven of the 135 chalk ads were still around by the time regulators tried to tally up fines. Verizon was charged only $1,075.

Harris at the Bureau of Street Services and Villanueva of the LAPD say there’s really no way to punish sidewalk stencilers unless they’re discovered multiple times or are caught in the act. As a result, Audi, GM and any others who want to etch their message on the sidewalks of L.A. can do so without repercussions.

“It’s like many other municipal violations. We just don’t have enough staff to go out and find every instance of this violation, so we’re just reacting to this problem when we’re notified that it’s occurring,” Harris says.

The market itself might render these ads obsolete, at least in comparison to huge, illegal signs draping L.A.’s high-rises, and digital billboards containing nearly 500,000 LED bulbs so intense they can be seen through the closed curtains of private homes.

“They’re kind of hard to read,” says Richardson. “Apparently our sidewalks aren’t that dirty.”

Contact the writer at berg@planetizen.com.

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