A number of bloggers have been looking into the Southern California habit of putting "the" in front of freeway numbers, as in "don't take The 5 because it's really backed up." People in other parts of California are alarmed at the spread of the habit throughout the state, and I've heard it creeping into Seattle jargon, as well.
Apparently, people in most places don't add the "the" to numbered highways. Its mainly an L.A./O.C. thing. We didn't here, either. I lived in the Bay Area in the mid-1970s, and because the place had so many named freeways, you got used to hearing about The Alameda or The Nimitz. Some knuckleheads — like car dealers — announced in their TV ads that buyers should come down to their lots on "The El Camino," which is a bilingual redundancy since "El" means "the" in Spanish, as we were informed brilliantly by Saturday Night Live's Chris Farley who told us that the translation of El Nino was "The Nino." No one needs a double "the." But now Bay Area residents are hearing references to "The 101" on traffic reports.
I've heard similar references here to The 520 and The 405, and I have a feeling since at least half of Seattle newcomers are from California, they're bringing their bad habits with them. But the example of the creeping "the" that really annoys me is placing that article before "Puget Sound." Even many local newscasters — especially in traffic and weather reports — are now routinely saying The Puget Sound. Here's an irritating reference to it in a recent Associated Press story.
The Puget Sound area, the Puget Sound basin, the Sound: All that's okay. But people, it is not "The Puget Sound," it's just Puget Sound, period.
You can categorize this idiocy along with "Pike's Place Market" (confusing it, apparently, with Pike's Peak), or perhaps chalk it up to the general Californication of the region, but please, citizens, let's try to maintain some regional linguistic standards.
Update: Here's the academic theory about how LA's "the" highway phenomenon started.