Locate your city water pressure regulator. It looks sort of like a big propane welding regulator. Gently tap it with the plastic part of a screwdriver and see if anything happens.
If your's is a rear bath, I think it's in the utility closet, perhaps under a pull-up floor.
Many of these old regulators don't work so well anymore. A lot of the folks here on the forum, myself included, use an inexpensive Marshall in-line regulator out at the spigot. These are less than $10 in the RV department at Wal-mart.
And welcome to the forum, of course. It's going to be interesting to hear how you fare if you plan to winter in the Airstream. Hey, what do I know about Alaska? Is it winter there already?
1975 Argosy 28 "Argosy"
1979 Excella 500 31 "Betsy"
1992 Lincoln Mk 7 LSC
2003 Dodge 2500 Cummins "TowHog"
"Lucy Loosehair" the cat - Airstream mascot
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