6 Warning Signs Your Well Is Biofouled
As a water well owner, you face unique water quality challenges. One of them is biofouling, the term used to describe the biological buildup and encrustations that can form on the well sides, bottom, screens, submersed components and pipes.
These buildups can impair well yield because they form dense, slimy mats that clog screens, block rock fractures that allow water to flow into your well, and reduce the functional well diameter in extreme cases. The majority of biomats are comprised of bacteria that feed off iron in the water. Because iron is abundant in the earth’s crust, it’s found in most aquifers, which means iron bacteria are, too.
Unfortunately, these bacteria and their myriad cousins proliferate rapidly, so prevention is the best defense. Expert drillers know this, so they disinfect everything that’s sent down the well bore as a basic preventative measure.
Drillers use down-hole cameras to look for biomats and slime, and water quality tests may reveal high concentrations of iron bacteria. Your senses, however, will often detect the problem first. Signs of biofouling include water that may:
- Have a reddish brown, orange, yellow or rusty tinge.
- Create rust-colored stains on or in fixtures, sinks, toilets, dishwashers and washing machines.
- Leave brown or rust-colored stains on laundry.
- Smell like cucumbers, decaying matter, fuel oil, sewage or sulfur.
- Have an unpleasant, foul or metallic taste.
- Look slightly green if the infestation is severe.
Once they become established, iron bacteria colonies can be difficult to eradicate. Over time colonies can damage the well casing, spread throughout your well system, migrate into water storage tanks and treatment systems, and cause clogs, pitting, holes and corrosion. While iron bacteria pose no known health risk, the thick encrustations often harbor E. coli or Salmonella and function as a safe haven that makes it more difficult to eradicate these dangerous bacteria.
If your well is biofouled, you need professional help. Common remedial methods include acid treatments, chemical disinfection (well shocking), hot-water jetting, steam injection and mechanical cleaning. Most biofouling cases require a combination of techniques such as mechanical cleaning followed by hot-water jetting or alternating acid and chlorination treatments. Because chemical treatments must penetrate through the heavily matted layers of both living and dead bacteria, they take time to work and may need to be repeated.
Once a well has been thoroughly cleaned, some owners opt for constant low-levels of chlorine in the well and/or household water supply to combat iron and other bacteria, a practice also common in municipal water systems. Because iron bacteria live in the aquifer, they can re-enter your well along with the water so even with preventative measures biofouling can reoccur.