Wikipedia:
When Sausalito was formally platted, it was anticipated that future development might extend the shoreline with landfill, as had been the practice in neighboring San Francisco. As a result, entire streets, demarcated and given names like Pescadero, Eureka and Teutonia, remain beneath the surface of Richardson Bay. The legal, if not actual, presence of these streets has proved a contentious factor in public policy, because some houseboats float directly above them. According to the San Francisco Chronicle, “State agencies say privately owned houseboats can’t be located above the underwater streets because the streets are public trust lands intended for public benefit.” The California State Lands Commission is reportedly pursuing a compromise which would move not the houseboats, but the theoretical streets instead.
I’m sure that makes sense. Now I wonder how that could be included in a Sausalito edition of Monopoly.