Taste or Odor of Must, Mold, Earth, Grass or Fish

This taste or odor is most commonly noticed in the spring, and is caused by geosmin, a compound that is known to cause taste and odor complaints.  Geosmin is naturally occurring and detectable in very low amounts.  It is an organic compound that is formed when algae, that blooms in surface water in the spring time, starts to die off.  Water with low levels of geosmin can be treated to remove the taste and odor, but higher levels that are seen in the spring after algae blooms are a problem to treat.  No health effects have been associated with geosmin, it is an aesthetic issue.

Because we do treat surface water, ESWA notices this problem in the spring when temperatures start to remain warm for a few days in a row.  Most of the time it only lasts for a few days to a week, and most consumers do not notice a taste or odor problem.  Some portions of the population have more sensitive taste buds and notice a taste or odor problem more readily than others.  If you do notice this taste or odor problem, please let us know by contacting our office at 610-258-7181.