Bonner Data Center
Missoula County is reviewing a proposed data center at 9314 Bonner Mill Road. The property is zoned industrial, and the current review is focused on the proposed industrial use's potential impacts on nearby residential properties, not whether a data center is an allowed use under the zoning in this location.
The proposal involves reusing a portion of the former mill building — commonly referred to as the planer building — for a high-performance computing (HPC) data center. This means most of the development would occur inside the existing structure, with no major expansion of the building footprint. Interior improvements would include constructing specialized rooms to house computer servers and supporting equipment.
The proposed data center would operate continuously, 24 hours a day, seven days per week, with minimal on-site staffing and relatively limited vehicle traffic associated primarily with maintenance and service visits.
The cooling system consists of a combination of adiabatic and evaporative cooling towers. The evaporative units would use water supplied from the site's existing fire suppression well rather than the domestic well system serving nearby residences. The applicant has indicated that no backup generators are proposed in the event of power outage.
The initial phase of the facility is expected to use approximately 7 megawatts (MW) of electrical power, with the potential to expand over time to utilize up to 29 MW, which is the estimated capacity currently available at the site.
May 11 - Third Application for Special Exception Application (Also found on the right hand side under documents).
- Click here for the special exception application.
- Click here for the supplemental narrative.
- Click here for the supplemental information 4-27-26.
- Click here for the supplemental information 5-5-26.
- Click here for the complete Bonner site plan.
- Click here tor the heat study site plan - Washington example.
Missoula County Consolidated Land Use Board (MCCLUB) public meeting: Wednesday, July 1, at 6 p.m.
- In-person location: 200 W. Broadway, Missoula County Courthouse, Sophie Moiese Room
- Virtual option: Residents can attend the meeting via Microsoft Teams. To join the meeting on your device, follow the links on the agenda that will be published on the Consolidated Land Use Board page.
Project summary
Current step: Special exception review
Application status: Complete application submitted; special exception in review with hearing scheduled for July 1, 2026
Expected hearing: Wednesday, July 1, at 6 p.m.
- The consolidated land use board hearing is currently scheduled for Wednesday, July 1, at 6 p.m. The meeting will take place in person in the Sophie Moiese Room of the Missoula County Courthouse, 200 W. Broadway, and virtually via Microsoft Teams. The agenda and information on how to join the meeting virtually will be available online prior to the meeting.
- The project will be subject to review by the Missoula County Consolidated Land Use Board, not the county commissioners. While the land use board at times only has authority to make recommendations to the commissioners, the board does have final decision-making authority in some cases, including zoning variances, zoning special exceptions and administrative action appeals.
What is being reviewed in this project proposal?
The Special Exception review is focused on whether the proposed industrial use, including its equipment and operations, would be compatible with nearby residential properties and whether potential impacts can be avoided or mitigated.
If a special exception is approved, the developers must apply for a zoning compliance permit. The permit application must demonstrate compliance with the County's data center zoning regulations, including requirements for new renewable energy and e-waste recycling. Zoning compliance permits are subject to administrative review and do not go through public hearing process.
Project review timeline
March 2026: Initial Contact
- Krambu and Missoula County Planning first discussed the proposed data center project.
March 25, 2026: First Special Exception Application
- The applicant submitted the first Special Exception application. County staff determined that more information was needed before public review could begin.
April 28, 2026: Second Special Exception Application
- The applicant submitted additional materials. County staff continued reviewing the application and identified remaining information needed for completeness.
May 11, 2026: Third Application for Special Exception (deemed complete)
- The applicant has submitted a complete application. A hearing is scheduled for July 1, 2026.
Late May/Early June: Public Notice Period
- The County will mail notices to property owners within 500 feet, publish a legal notice, and post notices near the property.
July 1, 2026: Land Use Board Hearing
- The Land Use Board is expected to consider the Special Exception request.
July 2026 or Later: Possible Permit Review
- If approved, Krambu may then apply for a Zoning Compliance Permit and other required permits.
MCCLUB may consider the following when reviewing this special exception:
- Traffic and site access, pedestrian facilities
- Noise and vibration from cooling equipment and other mechanical systems
- Water use, water quality, wastewater discharge, and potential cooling system effects such as vapor, drift, or icing
- Outdoor lighting and glare
- Visual impacts and effectiveness of proposed landscaping and screening
- Utility and infrastructure impacts
- Emergency access, fire protection, and hazardous materials management
- Any other circumstances relevant to compatibility with nearby residential uses
How can I participate?
Community members are encouraged to stay informed and provide public comment. Comments are most helpful when they address the topics the Land Use Board may consider during Special Exception review, especially potential impacts to nearby residential properties.
Follow this project page if you want be emailed when there are updates with this project.
Who's Listening
-
Phone 406-258-4946 -
Climate Action Program Manager
Missoula County Planning, Development and Sustainability
Phone (406) 258-3442
Documents
-
May 11 - Third Application for Special Exception Application (deemed complete)
-
complete_special-exception-application 032526 (1).pdf (9.04 MB) (pdf)
-
Supplemental Narrative 5-26.pdf (27.3 KB) (pdf)
-
Supplemental Information-4-27-26.pdf (10.5 MB) (pdf)
-
Supplemental information 5_26.pdf (1.14 MB) (pdf)
-
Bonner Site Plan COMPLETE.pdf (411 KB) (pdf)
-
heat study site plan_Washinton example.pdf (553 KB) (pdf)
-
-
April 28 - Second Special Exception Application
-
March 25 - Bonner Mill Data Center_Special Exception Application.pdf (817 KB) (pdf)
-
Correspondence
If the data center is equivalent to the power of 8,000 homes just to start that is way too much for Bonner and Missoula to handle. This data center will drive up electricity prices and continue to dry out our surrounding areas so a company can make money with a few AI tools or videos. Water is a basic necessity that we need more than some more AI tools or videos on the internet. No data center anywhere in Montana. We rely too much on our beauty for tourism and the enjoyment of Montanans.
In every community data centers have been installed in, there have been significant and detrimental impacts to the environment, exorbitant water consumption and overall costly impacts to both human and environmental health. I do not want to see one come to our community, and harm my neighbors, friends and family. I am strictly opposed to allowing this data center to exist in our community. It is horrible for all of us, our children, and the flora and fauna we share our home with. Please do not let this data center pollute our community. They can go elsewhere with their smog and water guzzling technology. They are not welcome here.
I'm quite concerned about the environmental impacts of this project, as well as the negative effects on quality of life on those living nearby. There's been so much work to clean up the rivers nearby in the past, and this is endangering their health again. There are many quantifiable health impacts of data centers, especially to air and water quality. With people living across the street from the proposed site, this project seems quite harmful.
My biggest question is, because it is well water out here- is this going to be liquid cooling? If so how will this impact our water table and wells. If this is to draw high kilowatt, what is being done to mitigate or lower our power bills, or are we expected to foot the cost spikes while the data center gets tax breaks? It isnt even goings to bring more than a small handful of jobs to a location that lost 100+ jib positions. How will this affect school children's development, mentally and physically? How many BTUs of heat will it be exhausting and dumping into the aquafier and air?
No. No. No. And NO. We went through this once before and it was a NIGHTMARE. Let's not do it again!