Backflow Testing and Prevention | Oakland & Macomb County

The short answer

Start with the complete system and the evidence

Backflow service checks the assembly protecting a particular water connection and documents its condition and test result. Sandison plans access, any water interruption, repairs, and reporting around the installed assembly and the responsible program's requirements.

What Sandison evaluates

A practical path from symptoms to the right scope

Clear diagnostic process
Licensed multi-trade coordination
Repair and replacement options
Residential and commercial support

Cross-connection control

The assembly protects the water supply only when its application, condition, and test are correct

Backflow work begins by identifying the assembly, protected hazard, installation orientation, shutoffs, drainage, access, freeze exposure, and the authority or facility requirement connected to the test. Sandison tests applicable assemblies, documents the result, and separates an adjustment or repairable component problem from an assembly that is damaged, incorrectly installed, inaccessible, or no longer suited to the application. A passing result reflects the assembly at the time of testing; it does not replace required maintenance or correct an unsafe cross-connection elsewhere in the property.

Repair and facility coordination

Commercial backflow service has to account for shutdowns, reporting, and return to use

Repair or replacement may require water shutdown planning, access coordination, parts identification, drainage control, insulation or enclosure work, and follow-up testing before the protected system returns to normal operation. Sandison communicates the observed failure, the work performed, the post-repair result, and any installation condition that remains outside the repair. For multi-tenant, food-service, medical, irrigation, boiler-fill, or process-water applications, the operating consequence of the shutdown is part of the service plan rather than an afterthought.

Primary references

Verify the local and credential information.

Michigan LARA — permits and plumbing-code administration

Common questions

What property owners ask

What information do you need before a backflow test?

The assembly location, identification, service history, and any notice from the water provider or facility are useful starting points. Access, shutoff condition, drainage, and the affected water use help determine the service plan.

Does a failed backflow test always require replacement?

Some failures involve components that can be repaired, while damage, an unsuitable assembly, or installation problems can require a different correction. The recommendation should identify the failure and include the appropriate follow-up test.

Will backflow work interrupt my water service?

Testing or repair may require isolating the protected connection, depending on the assembly and work involved. Sandison identifies the affected use and coordinates the shutdown and return to service before work begins.

Evidence and review

Why this page can be trusted

Service information based on Sandison’s documented trade scope and the technical references below. Contact the office to discuss the conditions at your property.

Technical lead: James Sandison, B.S. Mechanical Engineering, Oakland University. Michigan Mechanical License 7115733 · Michigan Master Plumber 8112263 · Michigan Plumbing Contractor 800-3618. Service information record: 2026-08-28.