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Monday 8am - 5pm Tuesday 8am - 5pm Wednesday 8am - 5pm Thursday 8am - 5pm Friday 8am - 5pm

Sentry

About Sentry
At Sentry, we’re not just building structures—we’re building opportunity, trust, and lasting impact. Flexible. Innovative. Results.

Self-performing EPC firm and design-build general contractor delivering concept-to-completion in construction, architectural & engineering, steel, electrical, mechanical, plumbing, welding & fabrication, manufacturing, crane, trucking, oil & gas workover Headquartered in Watertown, South Dakota, we’re a full-service EPC and design-build construction firm that self-performs across construction, con

trols & automation, electrical, mechanical, steel erection, manufacturing, engineering, architecture, and more. We take pride in doing things the right way—with grit, integrity, and a relentless focus on results. Our teams deliver high-quality work across agriculture, industrial, commercial, renewable energy, manufacturing, and water/wastewater projects throughout South Dakota and beyond. From local jobs to multi-million-dollar facilities across the Midwest, we bring flexibility, innovation, and real-world problem-solving to every project. We believe in investing in our people, growing the next generation of skilled leaders, and riding for the brand every step of the way. That’s the Sentry way.

08/14/2026

Completed in Mobridge, South Dakota

Sentry recently completed the City of Mobridge Water Treatment Plant Rehabilitation project.

Serving as General Contractor, Sentry coordinated construction within the operating facility while our South Dakota Service Division completed basin rehabilitation and field installation work.

The project included flocculation system components, process piping upgrades, catwalks and bar grating. Crews also installed flocculator paddles and baffle walls and built and installed drag paddles and trough systems within the treatment basins.

08/11/2026

Getting close to completion at SDSU in Brookings.

Our General Construction crew is wrapping up work on the AES Machine Shed for SDSU’s South Dakota Agricultural Experiment Station.

The large overhead door is going in and the team is working through the final details as the project comes together.

Great progress from the crew on this one.

SDState - Department of Animal Science South Dakota State University

08/06/2026

Next time you are at Prairie Lakes Wellness Center, look for Sentry inside the members gym.

Our wall sign gives members a quick look at the many services our teams provide throughout the region. We are proud to support a facility used by so many families, athletes and community members in Watertown.

Flexible. Innovative. Results.

08/04/2026

Built for a grain mill and conveying system.

Sentry’s Controls & Automation team designed, built and installed this custom control panel to bring the system together in one central location.

The panel gives operators a better way to monitor the process, control equipment and keep grain moving through the system.

07/31/2026

The final finish is one of the most important steps in the manufacturing process.

Our Manufacturing Division provides professional Paint, Finishing & Coatings for fabricated steel, industrial equipment, custom assemblies, and specialty components.

From surface preparation through the final coat, every project is completed with quality, durability, and long-term performance in mind.

Keeping these services in-house allows us to deliver consistent results while helping customers keep their projects moving.

07/30/2026

Reliable electrical service matters when your operation depends on it.

Sentry’s Electrical Division provides troubleshooting, repairs, upgrades, planned maintenance and emergency service for commercial, industrial and agricultural facilities.

From routine service work to complex electrical systems, our team has the experience and field support to keep facilities operating and projects moving.

Need electrical service? Give us a call at (605) 753-0880
Learn more at sentryusa.com.

07/29/2026

Steel is going up at the Florence School Addition in Florence, South Dakota.

Our South Dakota Service team has the columns set and is working on the truss and purlins for the pre-engineered building. The mechanical side of Sentry also has the plumbing piped and ready for the bathrooms.

Roof sheets are next as the two-classroom addition continues to come together.

Watch the latest project update:
https://youtube.com/shorts/ARfdnGctsWE?feature=share

07/28/2026

Fort Berthold Rural Water is honored to announce the grand opening of the new Bruce Fox Sr. Water Treatment Plant to be held on August 19, 2026 at 11:00 am in Mandaree North Dakota. This grand opening is open to the public and we hope to see you there!

07/24/2026

Take a look behind the scenes at the NSU Barnett Center bathroom remodel in Aberdeen.

Our General Contracting crew is completing the detailed tile work that is helping move this renovation toward the finish line.

Watch the crew in action:

https://youtube.com/shorts/VHKu6dLnGW0?feature=share

Northern State University Northern State Wolves

07/22/2026

Every fabricated steel component starts with precision.

From layout and measuring to welding and final fabrication, our Manufacturing Division focuses on the details that help ensure every structural steel component is built accurately and ready for the field.

Address

1928 Calvin Drive
Watertown, SD
57201

Opening Hours

Monday	8am - 5pm
Tuesday	8am - 5pm
Wednesday	8am - 5pm
Thursday	8am - 5pm
Friday	8am - 5pm

Telephone

+16057530880

Website

http://sentryusa.com/

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