A backflow preventer is a mechanical device that allows water to flow in only one direction, stopping contaminated water from flowing backward into the clean public drinking water supply.

Backflow can occur due to:

Sudden drops in city water pressure (water main breaks)
Back-siphonage from high demand on irrigation systems
Back-pressure from boilers, pumps, or commercial equipment

Without a properly installed and annually tested backflow preventer, fertilizers, pesticides, pet waste, bacteria, or industrial chemicals can contaminate the drinking water for you, your family, and the entire community.

Residential Irrigation Backflow Protection – Required in Raleigh-Durham & Greenville-Spartanburg

Nearly every home with an underground sprinkler system in The Triangle and Upstate SC is required by local ordinance to have an approved backflow preventer (RPZ, PVB, or DCVA).

Annual backflow testing is MANDATED by:

City of Raleigh
City of Durham
Town of Cary
Wake County
Greenville Water
Spartanburg Water System
Renewable Water Resources (ReWa)

Failure to test annually can result in heavy fines, liability, red tags, and water shut-off.

The Extreme Danger of Freezing Temperatures to Your Backflow Preventer

North Carolina and South Carolina winters bring hard freezes every year — often starting in November. Any water trapped inside a backflow assembly (even a few ounces) will freeze, expand, and destroy the device from the inside.

Common freeze damage includes:

Split or shattered brass bodies (non-repairable)
Burst internal check valves and relief valves
Cracked bonnets and seals causing massive leaks when thawed
Complete assembly failure → immediate red tag from the city

This damage is catastrophic, extremely expensive to replace, and almost never covered by homeowners insurance. Simply closing the shut-off valves does NOT protect the unit — water remains trapped inside and will freeze.

We strongly recommend professional backflow removal and indoor storage before the first hard freeze, along with full irrigation system winterization.

Common Backflow Failures We Fix Every Week

Frozen & burst assemblies (most common winter call)
Constantly dumping relief valves on RPZ units
Stuck or failed check valves
Clogged relief ports
Underground leaks from worn seals
Improper installations by non-licensed landscapers

Commercial & Industrial Backflow Requirements

Restaurants, medical offices, manufacturing facilities, schools, car washes, fire sprinkler systems, boilers, and chillers all require commercial-grade backflow preventers tested annually (or quarterly).

We are certified to test, repair, and certify:

Reduced Pressure Zone Assemblies (RPZ)
Double Check Valve Assemblies (DCVA)
Pressure Vacuum Breakers (PVB)
Spill-Resistant Vacuum Breakers (SVB)
Fire line backflow devices

Same-day electronic report submission to all required municipalities and water systems.

Why Choose Modern Plumbing and Backflow?

NC & SC licensed master plumbers
Current ASSE / ABPA certified backflow testers
Same-day or next-day scheduling
24/7 emergency backflow repair
We handle ALL paperwork and online submissions for you
Transparent service — no hidden fees

Don’t Risk Fines, Water Shut-Off, or a Frozen Backflow Disaster

Schedule today for:

Annual backflow testing & certification
Backflow repair or replacement
Pre-freeze backflow removal & irrigation winterization

Raleigh, Durham, Cary, Apex, Holly Springs, Wake Forest, Chapel Hill & The Triangle: (919) 341-1911 Greenville, Spartanburg, Greer, Simpsonville & Upstate SC: (864) 979-4050modernbackflow.com Licensed | Insured | Local | Fast | Compliant “Keeping Our Community’s Drinking Water Safe – And Your Pipes Freeze-Free.”

Backflow Done Right – Guaranteed.