Backflow Prevention — Protect Your Water Supply
Testing, repair, and installation of backflow prevention devices throughout the Triad.




















Backflow Prevention Keeps Contaminated Water Out of Your Supply
Backflow happens when water flows backward through your plumbing system — potentially pulling contaminated water into your clean supply. A sudden pressure drop, water main break, or heavy usage nearby can cause backflow, introducing chemicals, sewage, or other contaminants into drinking water.
All-Star Plumbing provides backflow prevention services throughout High Point, Greensboro, Winston-Salem, and the Triad. We install, test, and repair backflow prevention devices for commercial properties, irrigation systems, and residential applications where required.
According to the EPA, backflow incidents have caused serious public health problems, including illness outbreaks from contaminated water supplies. That’s why many municipalities require backflow prevention devices — and annual testing to ensure they work.
What Is Backflow and Why Does It Matter?
Understanding backflow helps you understand why prevention is required.
How Backflow Happens
Normal water pressure keeps water flowing in one direction — from the water main into your building. But if pressure drops suddenly (water main break, fire hydrant use, heavy demand), water can flow backward — pulling whatever is in your pipes back toward the public supply.
What Can Backflow Contaminate?
Anything connected to your water system. Lawn chemicals from irrigation, boiler chemicals from HVAC systems, sewage from drain connections, cleaning chemicals from commercial equipment — all can backflow into drinking water.
Cross-Connections
A cross-connection is any point where a potable water supply connects to a non-potable source. Garden hoses, irrigation systems, boilers, and fire suppression systems are common cross-connections that require backflow prevention.
Why Municipalities Require It
One contaminated building can affect the entire water system. That’s why water authorities require backflow prevention devices at cross-connections — and annual testing to verify they work.
Who Needs Backflow Prevention?
Backflow prevention requirements vary by municipality, but these are common situations.
Commercial Properties
Most commercial buildings require backflow prevention at the water service entrance. Restaurants, medical facilities, car washes, and industrial facilities typically have additional requirements.
Irrigation Systems
Underground irrigation systems are common cross-connections. Fertilizers, pesticides, and soil bacteria can backflow into the water supply. Most jurisdictions require backflow prevention on irrigation.
Fire Suppression Systems
Fire sprinkler systems connected to potable water require backflow prevention. Standing water in fire lines can become stagnant and contaminated.
Boiler Systems
Boilers often contain treatment chemicals. Backflow prevention keeps these chemicals out of the drinking water supply.
Medical and Dental Facilities
Restaurants and Food Service
Commercial kitchens, dishwashers, and beverage systems create cross-connections. Food service establishments typically require backflow prevention.
Car Washes and Laundromats
Chemical injection systems and high-pressure equipment create backflow hazards. Prevention devices are typically required.
Residential (When Required)
Homes with irrigation systems, swimming pools, or boiler heating may require backflow prevention depending on local codes.
Types of Backflow Prevention Devices
Different hazard levels require different devices.
- Reduced Pressure Zone (RPZ) Assembly
The highest level of protection. Contains two check valves and a relief valve that dumps water if either check fails. Required for high-hazard applications.
- Double Check Valve Assembly (DCVA)
Two check valves in series. Provides solid protection for low-to-moderate hazard applications.
- Pressure Vacuum Breaker (PVB)
Atmospheric vent that opens when pressure drops. Common for irrigation systems.
- Atmospheric Vacuum Breaker (AVB)
Simplest protection — a vent that opens under backflow conditions. Limited applications.
- Hose Bibb Vacuum Breaker
Simple device that screws onto an outdoor faucet. Prevents backflow through garden hoses.
Used for: Residential outdoor faucets.
Backflow Prevention Services
We handle all aspects of backflow prevention.
- Backflow Testing
Annual testing is required for most backflow devices. We test, document results, and submit paperwork to your water authority.
What’s tested: Check valve tightness, relief valve operation, differential pressure — all per manufacturer and code requirements.
Documentation: Certified test reports for your records and water authority.
- Backflow Repair
When a device fails testing, we repair it. Common repairs include replacing check valve seats, springs, O-rings, and relief valves.
After repair: We retest to verify the device now passes, then submit documentation.
- Backflow Device Installation
We install new backflow prevention devices — RPZ assemblies, double checks, vacuum breakers — sized and selected for your application.
Includes: Proper installation per code, initial testing, and documentation.
- Compliance Assistance
Not sure what you need? We can assess your property, identify cross-connections, and recommend appropriate backflow protection to meet local requirements.
how can we help?
Related Services
Emergency Plumbing
24/7 emergency plumber service for leaks, backups, and sudden plumbing failures.
Drains & Sewer
Drain cleaning, sewer inspections, and water or sewer main repairs done efficiently.
Commercial
Business & industrial plumbing, backflow testing, excavation through High Point and the Triad.
Remodels
Plumbing upgrades and renovations for kitchens, bathrooms, and whole-home remodels.
Emergency Plumbing
24/7 emergency plumber service for leaks, backups, and sudden plumbing failures.
Water Heaters
Installation, repair, and maintenance for tank and tankless water heaters.
Repiping
Water lines, sewer lines, gas pipes, underground pipe repair
Leak Detection & Repair
Find and fix water leaks, slab leaks, pipe leaks
Drains & Sewer
Drain cleaning, sewer inspections, and water or sewer main repairs done efficiently.
Commercial
Business & industrial plumbing, backflow testing, excavation through High Point and the Triad.
Remodels
Plumbing upgrades and renovations for kitchens, bathrooms, and whole-home remodels.
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Get Clear Pricing Before Starting
Before any work begins, we explain the problem, walk you through your options, and give clear upfront pricing. You know the cost before we start, no surprises and no pressure.
We Fix the Problem
Our licensed plumbers arrive prepared to fix the issue correctly the first time. If we can’t fix it, you don’t pay. Simple, honest, and backed by our guarantee.
Call and speak with a real person
No automated systems or call centers. When you call All-Star Plumbing, a real person answers 24/7, listens to the issue, and schedules help right away so you’re never waiting.
Get Clear Pricing Before Starting
Before any work begins, we explain the problem, walk you through your options, and give clear upfront pricing. You know the cost before we start, no surprises and no pressure.
We Fix the Problem
Our licensed plumbers arrive prepared to fix the issue correctly the first time. If we can’t fix it, you don’t pay. Simple, honest, and backed by our guarantee.
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Locations and Areas Served
Plumber Service Company Serving the Entire Triad
Backflow Prevention Questions
How often do backflow devices need testing?
Most jurisdictions require annual testing. Some high-hazard applications may require more frequent testing. Check with your water authority.
How much does backflow testing cost?
Testing typically runs $75-$150 per device depending on type and location. We quote before scheduling.
What happens if my backflow device fails the test?
We repair it. Most failures are fixable with new internal parts. After repair, we retest and submit passing documentation.
How long does backflow testing take?
Each device takes about 15-30 minutes to test. Multiple devices at one location are done in one visit.
Do I really need backflow prevention?
If your water authority requires it, yes. Beyond compliance, backflow prevention protects your water supply and your neighbors’ from contamination.
Can you remind me when testing is due?
Yes. We can set you up for annual reminders so you stay compliant without having to track it yourself.
Do you work on all types of backflow devices?
Yes. RPZ assemblies, double check valves, pressure vacuum breakers, and atmospheric vacuum breakers — all types.