Why?

Drivers, do you drive a vehicle that weighs over 3 tons? Check your local regulations, because the issue of vehicle weight restrictions on local streets is gaining publicity. The August 4 Slate article on California localities' implicit "SUV ban" seems to have initiated a debate that has continued in at least two Bay Area publications. Monday's SF Examiner explained the issue in terms of San Francisco:

Such ordinances, some of which date back to the 1970s, were established to prevent damage to The City's roads, said Jim Chappell, president of the San Francisco Planning and Urban Research Association.

The 109 restricted areas are scattered throughout The City in spots such as the windiest section of Lombard Street and the much-trafficked stretch of Market Street between Front Street and Van Ness Avenue. . . . 30 of the streets in question are marked with signs declaring them restricted to heavy vehicles . . . .

This might add another dimension to the anti-SUV backlash, but such regulations were not imposed by fiendish anti-SUV lobbyists. Quoted in a Contra Costa Times article, Ron DeFore, communications director of the SUV Owners of America: "This has not come up before, but it's not a surprise. . . . There is a never-ending attack on SUVs." He should not take the matter personally; a vehicle's weight inherently raises issues such as pavement stress and safety.

This rising discourse doesn't mean the restricted roads will see a drop-off in heavy vehicular traffic. San Francisco can't enforce the law because of too few officers, and Antioch won't because "these aren't the vehicles tearing up roads":

"In my mind, they're not what I'm looking for in a commercial vehicle," [Antioch police commercial enforcement Officer Joe Zanarini] said. "I'm looking at the big vehicles that tear up the roads and are taking out signs and fire hydrants."

Residential streets are engineered to handle heavy vehicles like fire and garbage trucks, he said. A passenger SUV might be over the gross limit of 3 tons, but those aren't the cars doing the damage, he said.

In a way, that's surprising. Before fashion turned in heavy pickups and SUVs' favor, a light-duty residential street would receive the usual automobile traffic plus a weekly garbage truck and the occasional fire engine or service vehicle. Now, the street gets the same vehicles, except the "usual automobile traffic" has likely increased in average weight as heavy pickups and SUVs' market share has risen. It would seem, then, that the street is subjected to more, and more constant, weight, and accidents* caused by these heavier, more regularly appearing vehicles will cause greater, more frequent damage to "signs and fire hydrants."

This is not to say that localities must crack down on heavy vehicles that exceed weight limits; choosing to deal with this, a local issue, is a decision reserved for local governments. Nevertheless, localities are perfectly entitled to decide greater enforcement is in their best interest and are not acting necessarily as agents of some anti-SUV conspiracy.