One of the great mysteries of resort life in the Coachella Valley is the sheer numbers of golf courses here, despite an annual rainfall of less than 5" per year. There are 125 courses here, using 18 holes as a definition as a course. This would include the nine 18 hole courses at PGA West, the three courses at Mission Hills, and so on.
In the eastern part of the valley - by La Quinta and Indian Wells - some of the courses use water brought up from the Great American Canal by the Mexican border via the Coachella Canal. The main purpose of this canal is irrigation in the Imperial Valley. It now also feeds golf courses and drains into a reservoir used to replenish the acquifer.
The Mid-Valley extension of the Coachella Canal was planned as a way to reduce the water drawn from the acquifer. About 20 facilities currently use this non-potable water, which is 90% Colorado River water. It's uncertain whether any water shortage would burden the golf courses here.
Any shortage of canal water would result in more water being drawn from private wells. Most golf courses have their own water infrastructure, established before the mid-Valley canal was built, and will be reluctant to switch away from acquifer water without firm guarantees of availability.