1. Comprehensive Zoning
2. Designated Open Space
3. Master Planning
4. Minimum space, parking, water rights, and carbon offsets for new builds.. (once again..zoning).

There are plenty of ways to limit growth that require some serious thought and sophistication.  A flat cap on growth is the stupidest and least thoughtful way to do so, and the externalities are countless, and the planners have not even attempted to considers the 'cons' or negative impacts of a such a broad and blunt instrument.