Backflow, which we introduced in a blog post earlier this month, is water supply contamination. It occurs when clean water reverses direction and suctions dirty water into the drinking water supply, necessitating backflow testing and certification.
In Charlotte, both residential and commercial (industrial) properties must have a backflow prevention device on all inground irrigation systems, and the device must be tested annually. The reason for such measures is because backflow incidents can cause major problems for towns and cities—in part because they are underreported and undetected.
Why Are Backflow Incidents Underreported?
Both residential and commercial backflow problems are underreported for several reasons—one of which is that many incidents go undetected (more on that in a bit). Other reasons include incidents of short duration, people not being aware that the incident should be reported or to whom to report it (Charlotte Water or your local Water Department in the Department of Public Works), and liability concerns.
Why Does Backflow Go Undetected?
Although water contamination is often evident through taste, smell, or discoloration, sometimes it’s far less noticeable. Here are a few reasons why backflow can go undetected:
- Sampling and monitoring. Random sampling may not detect transient, localized bacterial contamination. In addition, water may not be tested frequently enough to identify a backflow problem.
- Water pressure. Changes in water pressure can be indicative of backflow issues. However, conventional pressure-monitoring equipment may not pick up reduced pressure, particularly if it’s localized. Also, reduced pressure is often due to line breaks or flushing and therefore not immediately treated as an incident worthy of investigation.
- Health effects. It can be difficult to connect backflow incidents to an illness outbreak or chronic health effects. Even so, it’s often after people get sick that backflow is considered a potential cause, which means the initial incident went undetected.
Examples of Backflow Incidents
Backflow incidents can cause significant public health concerns. Show everything from propane to an agricultural herbicide to blood from funeral home to antifreeze have leaked into public water supplies across the country. A few examples in more detail illustrate how problematic this can become:
- In North Carolina, a pesticide contaminated drinking water for 23 households and a nearby office building. The problem: A water main broke at the same time an exterminator was filling a pesticide truck with water, dropping the water pressure and allowing the pesticide to enter the water supply.
- In Texas, a chemical that can burn skin and cause respiratory problems entered the public water supply from a chemical plant mixing tank: up to 24 gallons of the chemical was pumped back into the city’s water main—an amount normally diluted and used to produce 8,000 gallons of product. The problem: There was no backflow preventer on the chemical plant’s incoming water line, which left a cross-connection unprotected and allowed for backpressure into the water supply.
- In New York, a lawn maintenance contractor filled a hydroseed tank (seed, dye, and woodpulp) with water through unauthorized use of a hydrant. The water system became clogged up with the material and prevented water from flowing; a two-day advisory was put in place while officials flushed the water system. The problem: The operator neglected to install a backflow prevention check valve between the hose leading to the truck and the hydrant.
Expert Charlotte Backflow Testing and Certification Plus Backflow Preventer Installation
Looking to install backflow preventers? In need of backflow testing and certification? We are on Charlotte’s list of approved backflow preventer testers. Give us a call at 704-846-5371 or use our online contact form for service 24/7, 365 days a year.
Quick question & answer: Are backflow prevention devices required in Charlotte?
Yes! In Charlotte, residential and commercial properties are required to have a backflow prevention device on all inground irrigation systems, and the device must be tested annually. The reason for such measures is because backflow incidents can cause major problems for towns and cities- in part because they are underreported and undetected.