Tribal hydrologist helps develop water compact

By DAVID REESE

Lake County Leader

For over three decades, water scientist Seth Makepeace has lived in the numbers.

Makepeace, a hydrologist for the Confederated Salish and Kootenai Tribes, has been instrumental in developing the science behind the proposed water compact between the tribes and the state of Montana.

He not only helped develop the numbers and scientific facts behind much of the water compact, he has led dozens of meetings with the public and state lawmakers on just what the numbers mean.

Having helped flesh out the science behind the numbers, the water compact is a document is believes in. He has been a biologist with the tribes since 1990, and has worked on the compact since 2008. While political leanings have pulled the compact in many directions, Makepeace said his job was to stay securely in the science. “I’ve always kept my focus on the objective elements of the compact,” he said. “At the heart of the compact are a set of numbers, and everything builds from that. They’re not arbitrary.”

The proposed compact has been approved in the Montana Senate and now moves to the House for its first hearing April 11. As the compact moves its way through the Legislature, a recent report has added a new dimension to the compact discussion.

A report released March 5 about historic water use on the Flathead Indian Irrigation was inaccurate and did not reflect actual irrigation practices, Makepeace said.

Soil scientist Barry Dutton’s report shows that from 1989 to 1992 crop application of water at 37 farms in the Mission Valley was 28 inches. Makepeace said last week that Dutton included rainfall in his report, not just irrigation water from the Flathead Indian Irrigation Project.

Five members of the Flathead Joint Board of Control commissioned the water report from Dutton. The report was not requested from the Flathead Joint Board of Control. The report addresses historic use of water on the Flathead Indian Reservation. Historic use is a key component of the proposed water compact between the Confederated Salish and Kootenai Tribes and the state of Montana. Parts of the compact seek to preserve irrigation water rights at historic levels. 

While Dutton’s report shows irrigators applied 28 inches of water between 1989-1992, Makepeace said actual water use ranges, by crop, from 7.1 inches to about 15 inches. The average of all applied irrigation for all crop types for the 137 measured fields was 8.3 inches per season, and 80 percent of the 137 field irrigation measurements were less than 13.1 inches per season, Makepeace said.

The Dutton report comes as the 2015 Legislature prepares to deliberate the water compact in the House starting April 11. The bill passed last month in the Senate. Gov. Steve Bullock supports the compact. The recent report, Makepeace said, “Is not a make or break item, but it’s one piece of the puzzle.”

Dutton’s report draws heavily from a 1994 report, which was funded partially by the Bonneville Power Administration. Makepeace said the 1994 report “was a great piece of work,” and it’s the kind of work that “could go forward with the proposed Compact.” But Makepeace recently sent out a short statement and review of Dutton’s report. “We found in our review inaccuracies and we wanted to clarify that so that we  have a clear technical basis for people to make decisions,” Makepeace said. The report, he said, “leads the irrigation community to an incorrect conclusion” of historic use, Makepeace said. “It’s not at all what the ’94 report shows. The report he draws from tells a far different story.” 

Dutton was asked for comment on this article but did not return a phone to the Lake County Leader. Findings in Dutton’s report are drawn from an 

extensive set of field-by-field measurements of growing-season rainfall, applied irrigation water and soil moisture. The measurements were completed from 1989-1992 on 137 fields on 37 farms in the Mission Valley. “The 1994 work was a substantial contribution to understanding water conservation on the Flathead Indian Irrigation Project,” Makepeace said.

By using historic irrigation data from the 1994 report, the compact will provide enough water to meet historic use, Makepeace said. Historic water use as reflected in the 1989-1992 report can be met, “contrary to misleading assertions in the report commissioned by individual members of the FJBC,” Makepeace said.

The March 5 report also incorrectly describes the river diversion allowance concept, Makepeace said. River diversion allowances are a substantial modification between the 2013 and 2015 versions of the proposed compact, Makepeace said. The allowances define allocations of water at the source of supply to an irrigated area, and leave to the discretion of the irrigation project operator and irrigators how to distribute and administer water within the project. 

The Flathead Indian Irrigation project was built in 1904 and it draws on water sources from the Mission Mountains and the Flathead River at Kerr Dam to help irrigate over 137,000 acres in the Mission Valley. The Flathead Joint Board of Control represents irrigators in several districts in and adjacent to the Flathead Indian Reservation.

River diversion allowances were a negotiated compromise between the state and tribes after the 2013 compact was defeated in the Legislature. The allowances replaced what were called farm turnout allowances, which would have been measured as individual farm allocations of water. Makepeace said river diversion allowances do not define individual farm water allocations, they do not restrict re-use of water, and they do not restrict an irrigator’s ability to move water between tracts of land. 

Whatever numbers you use, whether they’re Dutton’s or Makepeace’s, the Flathead Indian Irrigation project in most years is unable to provide irrigation water across all project acres to meet potential crop water use, Makepeace said.

“This was recognized as early as a comprehensive 1939 report – decades before the implementation of interim instream flows on the Reservation,” Makepeace said. But, he said, The water amounts in the proposed compact demonstrate that historic water use measured over the 1989-1992 period can be met, “contrary to misleading assertions in the report commissioned by individual members of the FJBC,” he said.

Makepeace has led countless meetings on the compact, and last summer helped organize a meeting with state legislators to help them understand the important document. Only about 30 legislators attended. “There are leaders who understand it,” he said. “They understand the equity.”

Some legislators have said they avoided reading the compact because it was too long and complicated. “The compact is as simple as it can be,” Makepeace said. “But you can only make it as lean and mean as you can.”