Projects are currently underway or out for bid along the Milk River Project. Below is a list of the current projects:
Fresno Safety of Dams Projects
On-site construction started in April of 2023 with the primary focus being the installation of a dewatering system and the construction of a vertical sand filter trench. In 2024, construction efforts will be focused on staged excavation to the foundation, installation of drains, and embankment filter.
The Tailwater Fishing Access Site below the dam will be closed throughout the construction project to ensure public safety. There will be access to the river via the north side of the dam. All other fishing access sites will remain open throughout the project. Work requiring full road closure across the dam is tentatively scheduled for fall of 2024. Public notifications will be made 30-days in advance of closure.
This is a three-year project with a cost of $77 million, with the stakeholders responsible for $11.5 million dollars.
Updates…
- Embankment dam modification project awarded to NW Construction (Bozeman, MT).
- Spillway modification design will begin in fall of 2023 and construction is scheduled to begin in 2025 or 2026.
About Fresno Dam
The Fresno Dam, an integral part of the Milk River Project, has a history dating back to its construction in 1939, authorized under the National Industrial Recovery Act and approved by President Franklin D. Roosevelt. Its purpose primarily revolves around serving as an irrigation storage facility.
Key points about the Fresno Dam and its significance:
Construction and Purpose: Completed in 1939, the Fresno Dam is part of the Milk River Project in Montana. It was built to store water for irrigation purposes, a key component in supporting agricultural needs in the region.
Structural Details: The Fresno Dam is an earth fill dam with a height of 110 feet and a crest length of 2,070 feet. It contains approximately 2,105,000 cubic yards of material. The dam features an overflow-type spillway at the north end, allowing for a maximum flow of 51,360 cubic feet per second through a concrete-lined channel. Additionally, the outlet works discharge a maximum of 2,500 cubic feet per second through two 72-inch conduits. The dam’s reservoir can hold a total conservation storage of 91,746 acre-feet.
Safety Concerns and Corrective Measures: In April 2017, the Bureau of Reclamation initiated a Safety of Dams Corrective Action Study in response to identified risks of dam failure beyond the Reclamation’s safety guidelines. Historical settlement of the Fresno Dam’s foundation and the absence of a contemporary state-of-the-art filter and seepage collection system raised concerns. To minimize risks, the safety project includes measures to enhance spillway joint defenses. Interim measures, such as increased visual inspections and stockpiling of filter materials at the dam, have been put in place. However, there are currently no operational restrictions at Fresno Dam.
The ongoing Safety of Dams Corrective Action Study is a proactive approach to address potential risks associated with the dam’s foundation settlement and to ensure that the dam meets contemporary safety standards. The additional measures aimed at bolstering the spillway joint defenses signify a commitment to maintaining the safety and structural integrity of the Fresno Dam in the long term.
For more information, visit:
– www.milkriverproject.com/projects/fresno-safety-of-dams/
– United States Bureau of Reclamation: Fresno Safety of Dams
St. Mary Diversion Dam
About the St. Mary Diversion Dam
The St. Mary Diversion Dam and Canal, a crucial part of the Milk River Project in north-central Montana, was completed in 1915. However, over time, much of the dam’s existing structural components have deteriorated and are in need of replacement. To address these issues, the St. Mary Diversion Dam Replacement Project has been planned.
Key points about the St. Mary Diversion Dam Replacement Project and its impact:
Purpose: The primary purpose of the St. Mary Diversion Dam and Canal is to divert water from the St. Mary River into the St. Mary Canal, serving the Milk River Project’s irrigation needs, following the division of waters between the U.S. and Canada under the Boundary Waters Treaty. The replacement project aims to design and construct a new diversion dam and fish protection structure that complies with the Endangered Species Act (ESA).
Features of the Replacement Project: The new diversion dam is expected to include a low head diversion dam and rock ramp for upstream passage, a redesigned headworks structure, a canal fish screen, a check structure downstream of the fish screen, a fish bypass to safely return fish to the river, operation and maintenance buildings, and auxiliary features to ensure functionality and compliance with regulations.
Funding from the Infrastructure Investment and Jobs Act (IIJA): The IIJA has allocated $100 million for facilities that have failed in the past two years, leading to the prevention of water delivery for irrigation. The St. Mary Diversion Dam and Canal is the sole project that fits this specific criterion. The $100 million allocated from the IIJA doesn’t necessitate reimbursement by the Milk River Project water users and will be used specifically for the replacement of the St. Mary Diversion Dam and Headworks.
Primary Stakeholders: Key stakeholders involved in the Project include the Blackfeet Nation, the U.S. Fish and Wildlife Service, and the eight irrigation districts forming the Milk River Irrigation Project Joint Board of Control (Joint Board). Other stakeholders include more than 150 pumpers along the Milk River and six municipal entities.
The replacement of the St. Mary Diversion Dam and Headworks is a critical endeavor that not only aims to address the aging infrastructure issues but also aligns with environmental regulations to protect endangered species. The IIJA funding provides a significant opportunity to carry out this crucial infrastructure improvement without imposing financial burdens on the water users of the Milk River Project. Collaboration among various stakeholders is essential for the successful execution of this project.
Click below to view a digital 3-D model of the Diversion Dam Project:
For more information visit milkriverproject.com or contact Steve Darlinton, Project Manager, Bureau of Reclamation, at (406) 247-7322 or sdarlinton@usbr.gov
St. Mary Canal Modernization Project Watershed Plan – Environmental Impact Statement
An Environmental Impact Statement (EIS) is a comprehensive document that is prepared in accordance with the National Environmental Policy Act (NEPA) of the United States. NEPA requires federal agencies to assess the potential environmental impacts of proposed projects, actions, or activities that may significantly affect the human and natural environment. The EIS is a key component of the NEPA process and is typically required for projects that receive federal funding or involve federal agencies.
The primary purpose of an EIS is to provide a thorough analysis of the environmental consequences of a proposed project. It includes detailed information about the project, its alternatives, and the potential impacts on various aspects of the environment, such as air and water quality, wildlife, ecosystems, cultural resources, and the quality of life for affected communities. The EIS process involves the following key steps:
Scoping: This is the initial stage where the scope of the EIS is determined, and public input is sought to identify the key issues and concerns related to the project.
Draft EIS: A preliminary draft of the EIS is prepared and made available for public review and comment. This stage allows stakeholders and the public to provide feedback on the environmental analysis.
Final EIS: The final version of the EIS is prepared, taking into account public comments received during the draft EIS phase. It includes a more detailed analysis of the project’s environmental impacts and alternatives.
Record of Decision (ROD): After the final EIS is completed, the federal agency responsible for the project issues a Record of Decision, which outlines the agency’s decision regarding the project and any mitigation measures that will be implemented to minimize adverse environmental effects.
In the case of the St. Mary Canal Modernization Project, the EIS will examine various alternatives for modernizing the canal and associated infrastructure to improve agricultural water management. The EIS will assess the potential environmental impacts of the project, and its findings will inform the decision-making process by the involved federal agencies. This ensures that environmental considerations are taken into account when determining whether or how the project proceeds.
For more information, contact Jennifer Patrick at jenn@mrjboc.com or visit:
Milk River Watershed
Halls Coulee and St. Mary Siphon
The St. Mary River Siphon is a vital part of the St. Mary Canal infrastructure, designed for water conveyance in Glacier County, Montana. It consists of two riveted steel barrels, each with different diameters and operating characteristics:
Dimensions: The siphon consists of two barrels, each approximately 3,200 feet in length. The barrels transition from 90-inch diameter to 84-inch diameter at the river crossing and then back to 90 inches in diameter as they traverse up the valley slope.
Discharge: Each barrel has a different discharge capacity. The 90-inch section of the barrels can handle approximately 425 cubic feet per second (cfs) of water flow at a velocity of 9.63 feet per second, while the 84-inch section can handle the same flow at a slightly higher velocity of 11.05 feet per second.
Maximum Head: The siphon has a maximum head of 165 feet, which likely refers to the maximum vertical height difference that the siphon is designed to overcome when conveying water.
Construction History: The downstream barrel was constructed between 1912 and 1915, while the upstream barrel was constructed between 1925 and 1926. This information provides the age of the infrastructure.
Barrel Locations: The downstream barrel is partially buried, with approximately half of its length buried at a depth of 3-5 feet, while the right barrel runs entirely above ground. The difference in burial can impact their susceptibility to certain issues.
Maintenance and Repairs: The left barrel, which is buried, has experienced a series of issues over the years. These problems include seepage, corrosion, and buckling due to its burial. To address corrosion concerns, a cathodic protection system was installed in the 1950s.
Stability Concerns: Unstable valley sidewalls have contributed to the downslope movement of the steel barrels and concrete supports. This movement has led to buckling in the siphon barrels and compression of the expansion/contraction joints.
It’s apparent from this description that the St. Mary River Siphon is in need of modernization and repair due to its age, issues with buried components, and instability in the surrounding environment. The St. Mary Canal Modernization Project seeks to address these concerns and improve the infrastructure for more reliable water conveyance while minimizing potential environmental impacts, as outlined in the Environmental Impact Statement (EIS) mentioned earlier.
For updates on the current status of the project, visit:
Halls Coulee and St. Mary Siphon
For more information, contact Jennifer Patrick at jenn@mrjboc.com
or visit www.milkriverproject.com