Work continues on St. Mary Diversion as reservoir levels drop

Progress has been made with construction, which began about a month at the St. Mary Diversion to repair the structure that collapsed, Drop 5 near the end of the 29-mile system of dams, dikes, canals, gigantic metal siphons and concrete drop structures, as well as another structure, Drop 2, that was regarded as in danger of catastrophic failure.

Work on Drop 2 was planned for this year, and the work on Drop 5 was added after it failed May 17.

"We are finally seeing things come together on Drop 2," Milk River Joint Board of Control Project Manager Jennifer Patrick said. "The border crossing request for bring concrete trucks through a gate at the border has been approved, and I cannot thank the agencies that have gotten involved and the congressional delegation for going to bat for us and making this push."

The diversion was built more than 100 years ago by the Bureau of Reclamation as part of the irrigation system the Milk River Project, and also is used as a municipal water source by towns including Havre, Chinook and Harlem, and provides recreation opportunities.

Patrick said they tested the Emigrant Gap crossing Thursday morning with the first pour in the lower section and a cutoff wall of Drop 2.

On Drop 5, she said, they took the structure out of the bottom and continue to dewater the stilling basin. 

"We have had pretty good weather, a few showers, but the progress and grading on this structure will continue as the dewatering efforts get caught up," she added. "There is still a large amount of material to be moved, but as concrete and forming continue on Drop 2, it will allow our equipment operators to focus on Drop 5."

The dewatering efforts will be key on this structure because they are next to a riverbed, she said.

She said as they removed the structure, they were a little concerned about what they would find under the existing structure and they will do more testing, but the material appears to be more of a gravel type material not the black mud and muck they were expecting.  

"Time will tell there, but again we are hopeful," Patrick said.

Coordination efforts with the Blackfeet Tribe and Tribal Employment Rights Office are ongoing, but continue to be great from their point of view, she said.

She said the quarantine order has been extended for the Blackfeet Reservation and a lot of people are working from home and still providing them as much support as possible, adding that they have a tribal subcontractor onsite that continues to work on the roads, provide assistance in moving material and has been quite the asset for landowner and tribal contact information. 

They also have a few new employees joining the team from the Tribal Employment Rights Office this week to help with the concrete and forming, she said. 

Patrick said that last week, Sen. Steve Daines R-Mont., and Department of Interior Assistant Secretary of Water and Science Tim Petty, came up to the project and Brett Esplin, Steve Davies and Steve Darlinton with the Bureau of Reclamation had the opportunity to tour them around the drop projects. 

Tribal Council Chair Tim Davis, Virgil Clyde Last Star and DES Coordinator Robert DeRosier were also able to take a break from meetings to make a trip up and join Daines and Petty, she said, adding that a roundtable took place in Cut Bank after the tour to discuss the project, needs and the hardships faced in the basin with this failure and future ability to pay.  

Daines and Sen. Jon Tester, D-Mont., and Rep. Greg Gianforte, R-Mont., are trying to shift the funding for the system from about 75 percent provided by the users and 25 percent by the federal government so the federal government picks up about 75 percent of the cost of operation and maintenance.

  "As we continue major efforts on both projects this week, we will finally be able to start to put a schedule together," she said.  "(Tuesday) afternoon I received design drawings of Drop 5 from HDR for all parties to review.  After those and foundation decisions are approved, we will still have decisions to work through as we go, but the project becomes a little less fluid."

  She said the basin as they are near the end of the storage in Fresno Dam, they are hopeful all of these upgrades on the project help them to never face this issue in the Milk River basin again.  

The diversion provides much of the water that flows through the Milk River, which typically ran dry by fall in 6-out-of-10 years before the diversion was built.

The diversion has been shut down since the drop collapsed May 17.

At the time, Fresno and Nelson reservoirs, part of the Milk River Project that use water from the diversion, were at very high levels, but have been drawn down for irrigation use.

"We still have the goal of a total rehabilitation and cost share allocation flip, but this helps with some much needed infrastructure upgrades," Patrick said. "Reclamation staff also will be pouring concrete this week on upgrades to the siphons.  We still need to make a decision on Drop 1 repairs, and should be able to do that in the next couple weeks."

Fresno and Nelson reservoirs had above-average storage levels and have been used to provide continued irrigation deliveries up to this month.

"(This is an) incredibly impactful event with the failure of the structure and just a few collaborations from everybody involved to try to limit it and trying to get it fixed as possible, and set up Fresno Reservoir and the entire system for next year," Bureau of Reclamation Montana Area Manager Steve Davies said.

Davies said BOR is still making releases for irrigation.

The reservoir content is down to 41.2 percent full, which could also impact the fishery there.

Montana Fish, Wildlife and Parks Communication and Education Division Administrator Greg Lemon said at this time the impact is unknown.

"The situation with the irrigation structure at the St. Mary is in an emergency situation and so addressing it isn't a choice and it isn't a choice of when to do it - that needs to be done now," he said. "So, the future of the whole system including the irrigation and including the reservoir is depending on getting this work done."

He said FWP is working closely with the BOR and Montana Department of Natural Resources and Conservation on this and supporting that effort.

The health of the fishery is going to depend on a functional structure back in place, he added.

"The impacts we might see this year due to that work are just part of what happens in an emergency situation," Lemon said. "In some ways, from a resource management standpoint it's not any different than a major drought or other things like that where the situation is and the situation you have to deal with the reality that you are faced with."

He said FWP does expect impacts to the fishery, but exactly what those are going to be is completely unknown.

There are factors that go into it, he said, as the work continues. Some of the factors are weather and rain.

"We don't really know what the impacts are going to be to the fishery until it's going to be looking back and being able to look at what the water levels were and monitor what those impacts were to the fish," he said.

"Obviously, it's unfortunate that we're in sort of this emergency situation, but it's just the way it is and we're going to work closely with our partners to make sure that every step of the way we're keeping tabs on what's happening with the resource and doing everything we can to make sure the impacts are as normal as possible," he added.

Davies said BOR is going to reduce the amount of water being released starting next week.

"They are actually going to start ramping down next week, so everybody is still utilizing their one acre foot per allocation, which is half of what they normally get and it's all ending about right now," he said. "In fact, Alfalfa, Fort Belknap and Zurich irrigation districts, I believe are already off and so everybody is a little bit staggered in terms of when their allocation will be up because of the river distances that are involved, but we're still making relations right now for irrigation and municipal water."

He said BOR is releasing about 700 cubic feet per second or so.

Starting next week, he said, they will be reducing that to where, by the end of next week, they will be releasing about 100 cubic feet per second.

He added that 100 cubic-feet-per-second will be for the Fort Belknap Indian Reservation Project - they have a right to 75 of that 100 cubic feet per second and municipalities like Havre, Chinook and Harlem will utilize the remaining 25 cubic feet per second.

Fort Belknap irrigation project and Fort Belknap tribes have senior water rights, Davies said, so they get to continue for the rest of the season.

With concern to the overall level of Fresno Reservoir, he said, BOR has done this before.

"Right now, we're at 15 feet below full pool, we're projecting that we are going to down another 12 feet from where we are right now," he said. "In 2017, just three years ago we were lower than that, even, by an additional 3 feet from where we're projected to go, just from drought conditions."

It certainly is low reservoir level, lower than average, but the irrigation impacts are incredibly severe by reducing their allotments by 50 percent, he said.

He said the continued draw-down for Fort Belknap and municipalities will result in the reservoir being down close to about 27 feet below full pool  when they bottom out.

Depending on the timing of construction completion, he said, right now, it is likely to last till September, maybe October.

"We're optimistic we can move some water over to help raise Fresno level somewhat - we won't be able to fill it," Davies said. 

"I think Reclamation realizes this has been impactful on everybody - it's impactful for irrigators, it's impactful for the municipalities," he added. "We're going to make sure that municipalities have water through the winter for almost 14,000 people. We're ensuring that supply exists, but the irrigation is going to take a big impact and along with recreators that use Fresno."

He said they are optimistic BOR can move some water through the diversion this fall.