The City of Grants Pass has confirmed that a Geosmin bloom is the culprit in recent reports of smelly tap water.
Grants Pass officials said lab results received this week showed up to 60 parts per trillion in the water distribution system and over 70 parts per trillion in the raw water.
Geosmin is detectable by humans in concentrations as low as 4-5 parts per trillion.
Water distribution staff will be taking additional samples this week to determine if the bloom has subsided. Once the Geosmin levels are reduced, they will deep cycle the reservoirs and perform selective flushing to improve water quality faster than if they wait for the bloom to naturally dissipate in the distribution system.
In a press release last week, city officials said Grants Pass tap water is safe to drink despite the unpleasant odors. They said the odors should pass in a few days and that active carbon filters found in some household pitchers should mitigate the smell.
