What Does
Red Water Mean?
Red water is the generic term for water with high-particulate iron concentrations due to corrosion byproduct release. It is a common water quality-related customer complaint, as it causes tap water with objectionable tastes, odors and staining.
High iron concentrations in the source water can cause red water problems, while leaks can be caused by corrosive soil acting on the outside of the pipes as well as by corrosive water acting on the inside of the pipes.
Corrosionpedia Explains Red Water
When metal pipes corrode, the rust can break free and be carried to the end user in the water. This phenomenon, known as red water, can stain laundry and plumbing fixtures. In addition, corrosion in the distribution system can result in taste problems. Red water is usually caused by tuberculation and iron bacteria, while leaks are caused by pitting below the tubercles.
The most common indicators of corrosion in distribution systems are red water complaints and leaks. If the incidence of these problems increases in a certain area of the distribution system, then some sort of corrosion control may need to be undertaken.
During routine maintenance of the distribution system, it should be examined for signs of corrosion and scale. When pipes are removed and replaced, the old pipes should be visually checked for signs of tubercles, pitting or uniform corrosion, and for excessive scaling.
There are four general reasons for red water iron problems:
- A hole in the drop pipe in the well – As the water sprays across the well casing it oxidizes and turns red.
- Dissimilar metals – Galvanized fitting in a copper water line rusts and turns the water red.
- Arsenic contamination – An arsenic-bearing formation is disturbed, sulfuric acid is formed, which leaches the arsenic out of the formation. At the same time iron is leached out of the formation and turns the water red.
- Electrical – Electrical problems may also cause red water.
Phosphate inhibitors are one of the most common tools used to combat iron corrosion in distribution systems.