Just need to wait a few years.
http://leginfo.legislature.ca.gov/faces/billNavClient.xhtml?bill_id=201520160AB662
"This bill would require a person, private firm, organization, or corporation that owns or manages a commercial place of public amusement, as defined, constructed on or after January 1, 2020, or renovated on or after January 1, 2025, to install and maintain at least one adult changing station, as defined, for a person with a physical disability, as specified. The bill would require a facility to ensure that the entrance to each adult changing station has conspicuous signage indicating its location, and, if the facility has a central directory, ensure that the central directory indicates the location of the adult changing station."
"“Commercial place of public amusement” means an auditorium, convention center, cultural complex, exhibition hall, permanent amusement park, sports arena, or theater or movie house for which the maximum occupancy is determined to be 2,500 or more people. “Commercial place of public amusement” does not include any public or private higher education facility or district agricultural association."