This week will be one of celebration for many Whitefish leaders and residents after the city finalized a deal Tuesday that will safeguard more than 3,000 acres of land providing the bulk of the Whitefish water supply.

The Haskill Basin Project will prevent future development on 3,020 acres of working forestland owned by F.H. Stoltze Land & Lumber Co. The basin supplies 75 percent of Whitefish’s drinking water, with Whitefish Lake contributing the balance.

Whitefish Mayor John Muhlfeld said Wednesday the massive $20 million easement has been in the making for about five years, since he began working with the Trust for Public Land on the initial proposal.

“It’s not only a relief, but brings a lot of satisfaction to me that we’re able to deliver a conservation project to the city of Whitefish that will protect our water supply in perpetuity,” Muhlfeld said. “We don’t have to look far down the road to the city of Missoula to see what they’re facing, in terms of the challenges they’ve had to protect their water supply.”

The road to conservation has been bumpy at times, particularly when a block of Whitefish residents and business owners opposed the city’s proposal last year to raise the resort tax to cover the city’s $7.7 million share of the deal.

Ultimately, voters overwhelmingly supported a 2015 referendum to increase the city’s 2-percent resort tax to 3 percent.

In addition to the city’s share, Stoltze is contributing $3.9 million in donated land value, and a pair of federal grants supplied another $16 million.

Under the agreement’s terms, Stoltze remains the landowner while Montana Fish, Wildlife and Parks holds the easement.

Northwest Montana is rich in open spaces, and Montana Fish Wildlife and Parks regional conservation manager Alan Wood said the Haskill Basin acreage pales in comparison to other landmark easements along Bull Creek and the Thompson and Fisher rivers.

“The striking thing about this one was the value involved,” Wood said. “This is the most expensive project, per acre, that we’ve ever taken on.”

The Haskill Basin easement, brokered by the Trust for Public Land and signed by Whitefish, Stoltze and the state wildlife agency, came out to $6,600 per acre. The 142,000-acre Thompson-Fisher Project, by comparison, cost about $243 per acre.

That’s no surprise given the value of the development rights, to which the nearby high-end developments of Grouse Mountain and Iron Horse attest, according to Stoltze General Manager Chuck Road .

“We kept saying, the pressure to sell that land is tremendous,” Roady said. “We had one offer of $10 million for ten acres, or something like that. ... If you can live next to the ski area, the city and the lake, and still be in a forested, rural setting, you’d like it, too.”

Eventually the city listened. For more than a century, Whitefish’s water supply intakes were beholden to an informal agreement between the city and the lumber company.

“It was strictly a handshake, gentleman’s agreement,” Roady said. “They assumed that land was going to belong to Stoltze forever and trusted us with their water supply.”

For its part, Whitefish now owns the water supply intakes and infrastructure on Second and Third creeks, with Stoltze guaranteeing the city legal access to maintain the system in the future.

If the water supply issue provided the spark to get the city and company working toward a permanent solution, Alex Diekmann provided no shortage of fuel.

The longtime project manager for the Trust for Public Lands office in Bozeman, he was on the ground floor with Muhlfeld and Roady during the formative discussions that led to the Haskill Basin easement.

He died of cancer Feb. 1, just two weeks before his final conservation project was finalized.

Dick Dolan, the conservation organization’s Northern Rockies director, described Diekmann as a dedicated conservationist and “the consummate deal-maker.”

“He would find these great, valuable public projects that would benefit the public environmentally, recreationally and in this case, with the drinking water supply,” Dolan said Wednesday.

Roady noted it would be difficult to imagine the deal coming together without Diekmann’s tireless work with the various stakeholders in the community.

“That was tough for me. I wanted him to see it get done,” Roady said. “He and I started from day one on it. ... He was all in. It may have been a job to him, but it was also his passion, and I really respect him for that.”

Over the course of his career working for the Trust for Public Lands, Diekmann helped to conserve more than 100,000 acres of land in Montana, Wyoming and Idaho, Dolan said.

Given the complexity of the conservation deal — one that involved local conservation groups, multiple state and federal agencies and a degree of political controversy within the city of Whitefish — he said Haskill Basin provides an ideal example of Diekmann’s strengths as an tireless advocate and coordinator.

“That’s a legacy for all of us to enjoy and for future generations to enjoy. He had a knack for finding really high-value conservation projects,” he said. “This is a bittersweet time, but it’s also a very joyous time. Alex is joyful wherever he is right now.”

Reporter Sam Wilson can be reached at 758-4407 or by email at swilson@dailyinterlake.com.