State politicians are again proposing to allow subdivisions to dig hundreds of household wells to exploit groundwater without regulation, in spite of a court ruling to the contrary.

On Tuesday, a legislative committee voted to consider a potential bill that wouldn’t restrict exempt wells in the state unless they are connected together, such as for a subdivision water system.

Rep. Carl Glimm, R-Kila, proposed the bill on Monday after the Water Policy Interim Committee toured Bozeman-area sites related to water-rights issues in May. But Gallatin Valley irrigators weren’t pleased, said Senior Water Rights Coalition spokeswoman Christa Lee Evans.

“Our concern is the concentrated use of exempt wells when that’s used as a mechanism to avoid the permitting process,” Evans said. “Our concern is this is a take-it-or-leave-it proposition. There’s really not a lot of opportunity for compromise.”

Glimm’s bill is a reiteration of a 2013 bill – Senate Bill 19 sponsored by Sen. Bradley Hamlett, D-Cascade – which Gov. Steve Bullock wouldn’t sign without an amendment that allowed only one exempt well per 40 acres. The amended bill didn’t pass the Legislature, partly because of opposition from agricultural producers.

It was agricultural producers near Horse Creek outside Billings who first petitioned the Department of Natural Resources and Conservation in 2009 and then sued to get the department to redefine “combined appropriation” to stop a subdivision from sucking up all the groundwater near their farms and ranches. The 70-well subdivision caused the ranchers to lose 25 to 30 percent of their water right, said Trout Unlimited spokeswoman Laura Ziemer.

One exempt well doesn’t draw much – 35 gallons per minute maximum or 10 acre-feet per year, enough to flood a football field to a depth of 10 feet. The problem is that a 50-acre subdivision with one house per acre or more could use more than 500 acre-feet per year and that can strain groundwater supplies, depending on the location.

Prior to 1993, combined appropriation meant the DNRC would consider all the wells in a development as one exempt well. In other words, as long as all the wells didn’t use more than 10 acre-feet, developers didn’t need a water right but otherwise they did.

Then in 1993, the rule changed to say a developer would need a water right only if the wells were piped together. After that, subdivisions popped up everywhere, all with individual wells.

A subdivision developer didn’t need a water right but a farmer must have one to use the same amount of water to irrigate the acreage. Agricultural producers argued that the modified rule in essence gave subdivisions priority over senior water rights owners.

But it’s not just irrigators who suffer – fish and other aquatic organisms are threatened, too. As groundwater is drawn down, streams tend to run lower and become warmer because they are no longer replenished by the upwelling of groundwater. It can add yet more harm to streams suffering from reduced runoff as less snow covers Montana’s mountains due to climate change.

In a 2006 ruling, the Montana Supreme Court ruled that science had proven the connection between groundwater and surface water. No more water rights are issued in many river basins in Montana because the water is already over allocated. But if developers can dig unlimited numbers of wells, water could become scarce for all.

In October 2014, Judge Jeffrey Sherlock sided with the Horse Creek ranchers saying the unregulated proliferation of exempt wells was not in keeping with legislative intent when the exemption was created. Sherlock instructed the DNRC to use the original definition of combined appropriation until a final rule was written.

The Montana Well Drillers Association and the Montana Association of Realtors appealed Sherlock’s ruling to the Montana Supreme Court. The court heard arguments in May and a ruling is imminent.

On Tuesday, Well Drillers Association spokeswoman Rhonda Wiggers encouraged the committee to move forward with the bill so the rule could be finalized one way or the other. She said the well drillers have already spent $80,000 in court fees.

But Rep. Kathleen Williams, D-Bozeman, said Sherlock had returned the rule to the pre-1993 definition, indicating that’s probably how it should remain.

Rep. Zach Brown, D-Bozeman, said reintroducing the same bill that failed four years ago didn’t honor previous efforts at compromise.

“I think presenting this bill as a satisfactory compromise is not accurate,” Brown said. “I have to think that continuing to approach it with the spirit of compromise, that has to eventually yield fruit. This bill is moving the clock backward and not forward.”

Williams moved that two bills be put out to public comment: one bill with the post-1993 definition that failed in 2013 and one with the pre-1993 definition that was supported by Sherlock.

The motion passed unanimously. If either bill is approved, it will be submitted for consideration in the 2017 Legislature.