Anderson Ranch Dam

Above: Boise Project, Arrowrock Division. Anderson Ranch Dam. Aerial view of Anderson Ranch Dam & Reservoir. The reservoir was 84% full with 347,729 acre-feet of water this day. These photos were taken in a fixed with plane flown by Owyhee Air Research.

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BOISE — Whether to pump water from Anderson Ranch Reservoir into Elmore County-based Little Camas Reservoir will likely be decided by the potential economic impact to the Treasure Valley.

But advocates on both sides argue the impact is deeper than the economics of the issue. The case went before an Idaho Department of Water Resources hearing officer on Tuesday.

Elmore County, citing the need for more water, is fighting to have water pumped from Anderson Ranch Dam — or water district 63, a reservoir on the South Fork Boise River that supplies much of Ada County’s waterways — into a reservoir in Elmore County.

If passed, it would be the largest, and potentially first, interbasin transfer of a water right on record. Idaho Department of Water Resources’ Shelley Keen, a water rights permits manager, said he did not know of another case such as this — but noted it’s possible there is one on record he hasn’t found.

“It certainly isn’t very often we see an application for an appropriation this size,” Keen said.

Because there is little to no case law, the decision will likely come down to a provision in Idaho law. The code states that the application may be rejected if it would have an adverse effect on the local economy from where the water is drawn, which opposing lawyers do plan to argue in the weeklong hearing process.

According to a filing with the Idaho Department of Water Resources, Elmore County first submitted its application for a new water right in March 2017, then submitted an amended application in September 2017.

Elmore County argues that it could use 200 cubic feet per second, or 10,000 acre-feet per year, of water from the South Fork Boise River to replenish its rapidly depleting aquifer. 

Legal opponents of Elmore County include a group of canal and ditch companies, the Idaho Conservation League and the city of Boise.

“I think ultimately with the critical water issues that Elmore County faces we're looking for a sustainable future,” said Franklin “Bud” Corbus, an Elmore County commissioner.

Corbus said the county has sought other water sources for years, but he sees this as the only viable option.

“Ultimately it’s reached the point where we need to be a little bit more serious,” Corbus said.

However, attorney Bryce Farris questioned whether Elmore County had done everything it could, noting in his line of questioning that Elmore County had not explored purchasing access to a water right or purchasing a permit for access to water on the Snake River.

“Water is a critical issue in this area, and we need to pay attention to it,” Corbus said.

According to a report from SPF Water Engineering, the water would be stored at gravel pit sites northwest of Mountain Home near Canyon Creek, which would help recharge groundwater levels.

Farris also questioned whether the project is of adequate benefit to the citizens of Elmore County.

Corbus said were the application for a new water right approved, the cost to construct a pump moving water into the Camas Reservoir would cost roughly $30 million, and unless an alternative funding mechanism was enacted, the taxpayers would have to shoulder the burden.

“They understand that sooner or later Elmore County is going to have to pay,” Corbus said. “They all know if we don’t start now, we won’t have a future.”

Farris pointed out that the Mountain Home Irrigation District would most benefit from the additional water. Corbus owns property and is a water user along this irrigation canal, he said at the hearing.

Farris questioned why the taxpayers of the whole county should have to pay to transfer water from Anderson Ranch if it mostly benefits those using the Mountain Home Irrigation District water, which leaves out a significant portion of the rest of the county.

“Whether it be bonding or creating a water district, the citizens of Elmore County know and understand that’s a hurdle to overcome,” he said. Corbus had said earlier in his testimony that it would help replenish the aquifer for the whole county.

Corbus also said that the last thing Elmore County wants to do is harm Ada County’s supply of water, half of which comes from the Anderson Ranch Reservoir.

To Marie Kellner, who is representing the Idaho Conservation League in this case, the effects of drawing from Ada County’s supply, whether directly or indirectly, could harm wildlife and the flow of the Boise River.

“They’re seeking this water right because basically water is overallocated (in Elmore County),” Kellner said.

Taking from the Treasure Valley's water supply could have adverse effects on the river levels, which in turn could affect the fishery in the South Fork Boise River, a local economic driver.

Kellner added that there isn’t a study to show what the potential effects are, but lower water levels could prevent a generation of fish from hatching to the fullest potential.

“That is an economic value to the Boise River Basin,” she said.

While Elmore County is proposing taking flood waters or excess waters, Kellner is suspicious of the effects it could have on the river, noting decreased flows in the low-flowing winter months could have adverse effects.

“Right now, Elmore County has not been willing to condition the water right like that when we’ve asked them about it,” she said, adding there have not been adequate conservation efforts.

Regardless of which side emerges victorious, Kellner said it may be time for the Idaho Legislature to look at how water is diverted in Idaho.

“If we’ve got farmers on farmers fighting right now, maybe it’s time we look at this as a state and say, ‘OK, we need to do better,'” she said.

The hearing will continue through Friday. Public testimony for or against the application will take place from 5:30-7:30 p.m. Dec. 7 and 10 at the Idaho Department of Water Resources, 322 E. Front St., Boise.

Xavier Ward covers Ada County for The Idaho Press. You can follow him on Twitter at @XavierAWard.

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