Every once in a while, a reference to the Tidewater Virginia region has appeared in this and other newspapers as Tidewater, Va., as though it were a community--like, for example, such other nonexistent communities as Upstate, N.Y.; Downstate, Ill., and Baja, Calif., the latter (properly rendered as Baja California) being a state of our sister republic of Mexico.

Well, now, thanks--or no thanks--to the U.S. Postal Service, there is in fact a place called Tidewater VA. The postal service put its new regional mail-handling facility into operation as scheduled on Monday. It's similar to the one that serves, we say retching mildly, Northern VA.

Despite protests from history-minded people and some others, the Tidewater VA postmark now appears on mail sent from Norfolk, Virginia Beach, Portsmouth, Chesapeake, Suffolk, Newport News and Hampton.

Local officials have protested. The region's Republican congressman, Rep. G. William Whitehurst, wrote Postmaster General William F. Bolger citing "strong and growing opposition" to the new designation and asking that the postmark be changed. Most wanted the label Hampton Roads, the name of the port on which all the affected communities center.

Bolger said he would consider a change if an agreed-upon alternative could be found. But, said Tidewater VA postmaster Mark Hodges, even if Bolger approves it would take two to three months to retool.