There were two laws passed concerning per capita water use that were directed at water districts. There are no restrictions on individual behavior in regards to water use. This has been twisted into a ban on showers and laundry on the same day and the fake news was picked up by numerous outlets.
The law doesn't have to specifically say you can't shower or wash clothes on the same day to make it so.
Be stinky and sell one's daily water allotment to a neighbor.