Playa experts agree that while the recharge rate through playas is not fast enough to counter the amount of withdrawals due to irrigation agriculture, it can support farmers and ranchers with rainfed (dryland) crop production or grazing systems.
Researchers say firm data on the actual amount of recharge playas can provide is extremely variable, as might be expected. It depends on the size of a playa when it’s wet, how often the playa’s holding water, soil type, and depth to the water table.
So, when estimating recharge rates, scientists usually use ranges or averages. Three inches per year is typically used as an average recharge rate for the entire playa lakes region. To get a sense of what that means, visualize three inches of water the size of a playa moving toward the aquifer each year.
While this may not seem like much, the recharge rate through playas is 10 to 100 times more than in upland areas. And when you do the math, it adds up to quite a lot. Using the three-inch average recharge rate, a four-acre playa, which is a very small one, sends an acre-foot of water toward the aquifer each year. That’s 325,851 gallons of water — more than enough to supply a couple of families for a year.