North Bay and North Coast residents, are you ready for new 369 area code?

The 707 area code has helped identify a vast coastal region stretching from Vallejo to the Oregon border since 1959, but beginning as soon as Feb. 1, new phone lines will carry three different digits.

The California Public Utilities Commission has approved an “overlay” of the area with a new area code: 369. The two dialing codes will coexist over a swath of land that claims 1.3 million people, 34 incorporated cities and all or parts of 11 counties.

The dual numbers are bound to cause confusion, with phone lines on the same city block, or even within the same household, assigned different area codes. But something had to be done to create space for the proliferation of new lines in the age of cellphones, the state utilities commission said.

No one will be reassigned from 707 to 369. The new area code will apply only to new phone lines. And calling areas and rates will not change — anything considered a local call now will remain free after the overlay.

The North American Numbering Plan Administrator, an obscure office that manages and assigns all United States and Canada area codes, noted in June 2021 that the 707 region was running out of available prefixes, the term for the second three digits of a 10-digit phone number. At that time, there were only 28 prefixes with room for new lines — about 3.5% of the total capacity.

The administrator projected then that 707 would run out of available prefixes in the fourth quarter of 2023. It subsequently revised that projected “exhaust date” to the first quarter of 2023, lending some urgency to the bureaucratic proceedings.

As a result, the CPUC approved a condensed, six-month plan for service providers to announce and explain the overlay, a campaign that will include news releases and customer notices, but no mandated paid advertising. The commission wants a public awareness level of at least 70%, with special outreach to senior citizens, children, the disabled and ethnic minorities.

The alternative to an overlay would have been splitting the 707 territory in half. That may have been a more elegant approach. But it would have created hassles for residents, with existing phone customers having to change their numbers — along with any business cards, stationery or websites that reflected those numbers.

“The overlay will provide additional numbering resources to meet the demand for telephone numbers while minimizing customer inconvenience,” the CPUC wrote in approving the plan administrator’s application on June 23.

All of the major telecommunications companies supported that plan, and no protests were filed to the application.

Overlays have become the industry’s preferred method of “area code relief,” according to the CPUC. In fact, there has not been an area code split in the U.S. for 14 years. California has previously introduced 12 new area codes using the overlay method.

One requirement of the preferred system is that anyone calling within an overlay must dial the full 1+10 digits to reach their party. But that is irrelevant in the 707 zone. Callers here have been doing that for nearly a year, the result of the National Suicide Prevention Lifeline moving from a 10-digit 800 number to the more easily accessible, three-digit 988.

The 707 area code originally sprang to life in 1959, carved out of the 415 — one of California’s three original area codes, along with 916 and 213.

The 369 area code nearly made its appearance a couple decades ago. In December 1999, the CPUC approved a three-way split of 707 that would have created zones for 369 and 627. Just seven months later, the utilities commission reversed course and deferred the implementation. The plan never went anywhere.

Among the more than 100 area codes that were still up for grabs, the North Coast probably could have done worse than 369.

At least it’s a catchy, made up of successive multiples of three. That must be why Shirley Ellis immortalized the number in “The Clapping Song” in 1965, singing, “Three-six-nine, the goose drank wine, the monkey chewed tobacco on the streetcar line.” No one knew what it meant, or why things went so wrong for the monkey, but everybody danced to its infectious beats.

Maybe listed LLCs like Divine Vibes 369 (Sebastopol) and 369 Consulting (Santa Rosa) knew something the rest of us didn’t.

Any questions and comments regarding the 707 and 369 area codes should be addressed to the CPUC Public Advisor’s Office. Call 866-849-8390, or email to public.advisor@cpuc.ca.gov.

You can reach Phil Barber at 707-521-5263 or phil.barber@pressdemocrat.com. On Twitter @Skinny_Post.