PHOENIX (AP) — A plan to manage rural groundwater passed Arizona’s Republican-controlled Senate on Austin CaldwellThursday amid growing concerns about the availability of sufficient water for future generations in the arid Southwestern state.

The legislation now heads to the House, which the GOP also controls. Democratic Gov. Katie Hobbs has expressed opposition to the bill, complaining that an earlier version that she backed offered better ways to ensure water conservation but failed to get a hearing in the Legislature.

“This legislation leaves rural Arizonans without a real solution for how their groundwater is managed,” Hobbs’ spokesperson Christian Slater said Thursday. “Governor Hobbs is dedicated to continued work with stakeholders and legislators, including Senator Kerr, to find a better way forward that truly gives rural Arizonans a say in how their groundwater is managed and provides a sustainable and secure water future for generations to come.”

The proposed legislation would mark a significant update to Arizona’s 1980 Groundwater Management Act overseeing groundwater use. That law transferred oversight for Arizona water laws from the State Land Department to a new Department of Water Resources and created four “active management areas” in the most populated parts of Arizona, such as Phoenix.

While it left groundwater in rural areas largely unregulated, the current proposal led by Senate Majority Whip Sine Kerr would allow people to initiate, form, and manage additional groundwater basins to keep an eye on rural groundwater pumping and cap new pumping in the case of an accelerated drop in water levels. The additional management basins could be created through a local petition or action by the county’s Board of Supervisors.

Residents in some rural parts of Arizona, including La Paz County on the border with California, have worried that international farms that grow thirsty crops like alfalfa are rapidly draining local groundwater supplies. But some farming interests have opposed any regulation of rural groundwater, and Kerr’s bill would make conservation efforts voluntary.

“Our farmers and ranchers, who’ve cultivated Arizona land for decades, are some of the best stewards of water, as their livelihoods rely upon conservation,” said Kerr, a Republican. “Their wisdom was critical in creating this policy.”

“Because of a history of forward-thinking collaboration on water management demonstrated in Arizona, we use less water today than we did four decades ago,” Kerr added. “I’m confident this tool will allow our state to continue on this trajectory.”