System treatment

Treating the Microirrigation System for Iron Bacteria

Venturi injector plumbed across a valve used as a pressure drop Photo: L. Schwankl

Although the source of iron bacteria contamination is usually the well, the iron bacterial contamination can also be present in the microirrigation system. The treatment is to use a biocide to eliminate the bacteria. This is most frequently done by chlorinating the system. For more information on chlorinating a microirrigation system, click here.

A caution regarding chlorinating to mitigate iron bacteria problems. The iron bacteria use the dissolved ferrous iron in the water as an energy source so whenever iron bacteria are present, dissolved iron is also present in the water. This dissolved iron can be a chemical precipitate clogging hazard. Chlorine is a very strong oxidizer so adding chlorine to water with dissolved iron in it will cause the rapid precipitation of ferric oxide. This insoluble precipitate can clog emitters also so it should either be filtered out or allowed to settle out in a reservoir, prior to being used in the microirrigation system.