A water scientist says California could be managing its water resources - above and below ground - together.
Famiglietti says California manages surface and groundwater separately, but that's not the best way to do it.
"Another aspect that we have to think very carefully about is managing our surface water and our groundwater jointly rather than as independent entities," says Famiglietti.
The California State Water Resources Control Board proposes reducing mandatory water conservation requirements. But Famiglietti says it's too soon.
"I think we need to keep those conservation measures in force. We have had really only average amounts of rain and snowfall and most of that has been in the northern part of California," he says.
While skimpy precipitation and reduced snowpack has often been called the "new normal" in California, Famiglietti says more data is needed to determine whether that "new normal" has now become the norm.
"All indications are there that we are approaching this 'new normal,'" says Famiglietti.
Famiglietti says last winter didn't bring enough precipitation to end the state's water supply deficit, but three or four more winters like winter 2015-16 would help.
The statewide Sierra Nevada snowpack was 51 percent of normal on May 11, 2016.
The California Department of Water Resources has released proposed regulations that are intended to guide groundwater management.
The regulations are mandated to be in place by June 1 as part of the Sustainable Groundwater Management Act.
One part of the Act requires local agencies to draft plans to bring groundwater aquifers into balanced levels of pumping and recharge.
Famiglietti says that's a benefit.
"I think the level of local control is very important," he says. "The conditions that would determine whether or not a region is, can come into sustainability, those are going to vary quite a bit geographically. So, I also think it allows for a lot of local, local buy-in. So I think it's a very sound approach."