Earlier this month, Gov. Gavin Newsom signed Senate Bill 72 into law: a piece of legislation that may be of particular importance for both our region and the state. If predictions by stakeholders about SB 72, authored by Sen. Anna Caballero, D-Merced, turn out to be true, this new law might amount to a minor revolution in state water planning.

The way California currently handles its contentious water policy feels like little more than quick — and seemingly ill-thought out — reactions to whatever the latest crisis may be. This new law, however, will require the Department of Water Resources to set specific targets for the amount of water to be provided for urban and agricultural use by 2050, as well as the needs of the state’s tribes and its environment.

Notably, what appears revolutionary about this new law is that by setting long-range targets for the major sectors of water use, policymakers can track the state’s progress toward attaining goals and make adjustments and improvements along the way as needed to reach them.

California uses between 60 and 90 million acre-feet of water a year (one acre-foot is nearly 326,000 gallons), but it’s getting hotter and drier as climate change takes its toll. That means the demand for water will likely increase while supplies diminish.

How will the state set water targets?

Assuming that nothing is done to increase those supplies, this is what makes sense about the new law: It gives the state time to find or create additional supplies to reach the 2050 targets. Moreover, it commits not just the state, but all the urban, agriculture and environmental interests that backed the bill to embracing and defending these targets over a long period of time (until 2050).

Details are vague on how these targets will be set, and this is cause for concern. Californians have made an art out of fighting over water, and it’s hard to imagine that Caballero’s legislation (now law) will bring an end to that. It also appears that the Department of Water Resources itself sets these targets, but then must consult with a new advisory committee packed with various stakeholder groups — including urban, agriculture, tribal and environmental interests. The department must also hold regional workshops to solicit more information.

The new law requires that science be used regarding current and projected water availability (as well as future storage capacity) and changing demands for water as land use patterns and climate change.

What happens, though, if it becomes clear in the five-year iterations of the water plan the Department of Water Resources is required to publish that the state is not on track to reach its 2050 targets? Are the long-range targets changeable? If so, who will change them? If new water storage infrastructure is needed to secure additional supplies (and it seems the Department of Water Resources must come up with 9 million acre-feet of new water by 2040), will the state pay for it?

Can California preserve agriculture and environment?

The governor vetoed this bill last year partially out of fiscal concerns. Will policies such as the California Environmental Quality Act be loosened to make it possible to quickly build new infrastructure to capture this water? Where does the controversial Sustainable Groundwater Management Act fit in, since more groundwater storage is the most sensible way to store additional water supplies? Overall, will it be enough to keep agriculture strong in California while restoring its environment and bringing fish, like salmon, back from the brink?

And what happens if the science we use today is not accurate enough in predicting the future, or overly optimistic scientific forecasts get used to set the 2050 targets? What if existing and projected water supplies turn out to be inadequate to meet the targets, even if we get better at water storage, recycling and capturing stormwater run-off?

One cannot help but remember what happened with the Colorado River. In 1922, the seven states (including California) negotiated a compact with the federal government for dividing the river’s waters for urban and agricultural use. Unfortunately, the scientific measures of available water turned out to be over-optimistic by at least 1 million annual acre-feet.

Then, in 1965, the U.S. Supreme Court required the needs of Native Americans to be taken into account. The result has been decades of expensive litigation between the states using the Colorado River. Today, with climate change reducing the Rocky Mountain snowpack so that the river is diminishing, the states have spent years trying to negotiate lower river targets. So far? No agreement.

Let’s hope California’s new law is as successful as proponents say it is and doesn’t lead us down a rabbit hole.

Tom Holyoke is a professor of political science at California State University, Fresno. Laura Ramos is director of the California Water Institute at California State University, Fresno. Cordie Qualle, assistant director of the California Water Institute at California State University, Fresno, also contributed to this piece.