1) Population - As of 2013 the U.S. Census Bureau estimated Santa Cruz's population at 62,864 [1], versus ~860,000, for San Francisco alone, as of 2015.[2]
2) Water - "The SCWD currently has four water supply sources: 1) surface water diversions from three creeks and one natural spring on the Santa Cruz Country Coast; 2) surface water diversions from San Lorenzo River; 3) surface water from Loch Lomond Reservoir; 4) groundwater extracted from the Purisima Formation by the Live Oak well system."[3] The recent drought represented a sobering reality for residents, regarding capacity of the existing system.
3) Geography - Perhaps someone more knowledgeable on this might weigh in, on this, but the area comprises a number of marine terraces; you go from ocean to hilly redwoods in about three miles, or less, with most people living primarily on the marine terrace plateaus. You could develop it, I guess (?)
It's a gem, for sure, and not saying it's impossible; I guess we'd have to define the characteristics of what a New SF would represent, for you. : o )
[1] https://en.wikipedia.org/wiki/Santa_Cruz,_California
Source: Lived here 10 years.
It's not an easy problem to solve.
Those proposing them and voting to support them do not live in the impacted area and throw up their hands when residents complain -- "we need housing".
The question is how they would ever get the might?
> Seems to me that creating a competing city is easier and quicker than reforming one.
Santa Cruz is an existing city, and apparently one that you propose reforming into your ideal of what San Francisco should be. Why is that easier to reform that existing city than San Francisco?