Mystery of the Month - January

Have you been hiking a creek and noticed an orange slimy/oily goopy substance in the water?  If so, there is very good chance it is a form of iron-oxidizing bacteria.  These iron-oxidizing bacteria can generally be found in moist or saturated areas with a good amount of iron in the ground.  Generally, these ‘iron seeps’ tend to be found during the wetter months of the year, though if conditions are right they can be present year round.  A much more common place to find these bacteria is in toilets, backyard wells and other home water systems.  Iron-oxidizing bacteria are slightly different than most other bacteria because they do not require organic matter to feed; instead they flourish by combining dissolved iron with oxygen.  It is during this process that the ‘orange-slimy goop’ is made.

Are iron-oxidizing bacteria a health concern? The short answer is NO, iron bacteria are not a health concern.  However, iron bacteria can produce unpleasant tastes, stains and odors in your drinking water.  There are a couple ways to treat the bacteria.  The most common method used is physical extraction followed up by a "cleaning" treatment, with chemicals such as surfactants (soaps) or other disinfectants.  Generally, treatment is only needed in drinking water systems, to help remove unpleasant taste.

If you happen to come across any iron-oxidizing bacteria in the District (or anything else that does not look 'normal'), please call Dave Vlasin, Water Quality Technician at 651.792.7972.  He will run out, take a sample and try to figure out what it is.

David Vlasin
Water Quality Technician