Iron (Manganese) and Sulfur Bacteria in Your Well Water

Presence of bacteria in your drinking water supply does not necessarily pose a health hazard. Certain types of bacteria in household water are more of a nuisance issue. Your water may test negative for coliform and E. coli, but it may still contain other bacteria, typically nuisance bacteria. The two most common types of nuisance bacteria are iron (manganese) and sulfur bacteria. Iron (manganese) bacteria are generally more common than sulfur bacteria because large amounts of iron can be present in ground water. Iron and sulfur bacteria can live together in a household water supply system, so it can be very difficult to determine whether the problem is from one or the other, or both.

Water tests looking for the presence of iron bacteria are seldom recommended and are generally not required. Instead, the confirmation of the presence of iron bacteria is usually based on visual inspection. The unmistakable “rotten egg” odor of hydrogen sulfide gas is the most obvious sign of a sulfur bacteria problem.

Once iron bacteria are well established in a household water supply system, their complete elimination is extremely difficult or even impossible. Preventive measures are more critical and effective than corrective actions. This publication includes some simple preventive measures as well as control and treatment options.