Iron Bacteria: The Orange Sludge In Your Basement

iron bacteria in toronto basement Is that orange sludge in my basement dangerous?

Did you ever dig down into a pool of water and find an orange sludge where ferrous iron was present? While it’s not dangerous as such, it does impart an unpleasant taste, appear oily and look like unprocessed sewage. We usually find this frequently in older Toronto basements, especially leaky basements.  Many homeowner insurance policies don’t cover this in the small print.

While Iron Bacteria (for this is what the orange sludge is) are not injurious to human health, they do stain water a rusty brown – and anything else they come in contact with like clothes and soft furnishings.

Iron Bacteria Facts

Iron bacteria are living micro-organisms that oxidise rusty iron that’s dissolved in water. They do this by attaching themselves to the iron object the water’s passing through. This could be a supply pipe or a sump pump. It could equally be a rusty piece of iron outside your basement in the backfill.

They are also prolific procreators of their species. In no time at all they’ll have babies attached on their backs. Within months the colony becomes a plaque-like biofilm. The inhabitants have found a place where they can live off rusty water, in the same we survive by breathing oxygen.

iron bacteria in richmond hill home

How the Problem Starts

While iron bacteria are naturally present in ferrous rocks (for example those containing manganese) chopping up a basement floor to install drainage introduces the oxygen they need to thrive on. All that’s needed is a piece of rusty iron left behind, or even exposed rebar cause by inadequate concrete pours.

Builders frequently exacerbate the problem by installing open drains inside basements to take bacteria-rich water away. Iron bacteria just love oxygen-rich environments like these. This adds power to the argument that the only way to stop water-penetration professionally, is outside basement walls.

Ways of Dealing with the Problem

If you have iron bacteria in your water-supply my advice is to stay away from chemicals that could be compounds of acids, disinfectants and biocides. These may well treat the symptoms, but they’re the last thing you want entering nearby streams and ponds. If you have a septic tank they’ll also kill it stone dead, which is a whole lot worse than something harmless, except that it looks like orange sludge.

It’s far more responsible to pump water that’s 140° hot through the system. This effectively pasteurizes the bacteria and kills them stone dead. You don’t need a high-pressure pump to do this. Your diesel-fired burner, 300 psi delivery and a handy bleed point are all you need.

Conclusion of the Matter

While iron bacteria isn’t necessarily dangerous to human health, it is an annoyance and can can effect the water quality in your home if left untreated.  If you see that orange sludge throughout your basement, it may be a sign that you have water problems and may need to call in a professional to find the source of your leaky basement.

Have questions about water or mold in your basement?  Contact us here, we’re happy to answer any questions.



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NuSite Group is a Toronto based basement waterproofing and foundation repair company that specializes in Basement Waterproofing, Basement Lowering, and Foundation Repairs. Call us today at 416-622-7000 or 905-731-1228 for a free in-home estimate and inspection.

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