The City of Fremont says it has found the cause of the bad-tasting, musty-smelling drinking water that residents in the Sandusky County city have complained about, and testing shows treatment levels are now falling. Officials identified the compound as MIB, or 2-methylisoborneol, a substance discussed in testing alongside geosmin that can give water an earthy taste and odor even at very low levels.
City officials stressed that the compounds do not affect health. City official Gross, as quoted in the Fremont News-Messenger, said the important thing is that the water does not pose a health risk, and that the problem is limited to the musty odor and taste residents have noticed at their taps.
Gross said the treatment now under way is working and that MIB levels are declining. The city has been on the phone with the EPA every day as it works through the problem, using guidance and regular communication with the agency while the treatment continues and new test results come in.
The treatment involves a product called Green Clean Pro, which the city is using to pretreat water in the reservoir before it enters the plant. Inside the plant, the city has added more potassium and carbon to filter and purify the water. By pretreating the water at the reservoir, officials are working to reduce the compound before the regular plant treatment begins.
Test results from Eurofins show the improvement in numbers. A first test on October 6 measured 330 nanograms per liter in the reservoir, and a second sample on October 13 improved to 170 nanograms per liter. Tap water samples showed a similar drop, from 120 nanograms per liter on October 6 to 40 nanograms per liter on October 13, a decline of 67 percent. The city’s goal is to get levels below 25 nanograms per liter, which should eliminate the taste and odor problem.
Another sample was sent on October 20, and the city said it will make those results public. Officials cautioned that improvements may not be noticeable immediately for every household, because water takes time to travel from the reservoir to faucets, and that timing varies with usage across the system.
Fremont is not the first Ohio community to deal with the issue. Upper Sandusky and Findlay had similar problems, and Fremont used guidance from those cities as it developed its response. For residents, the next update to watch is the October 20 sample result, which will show whether levels have continued moving toward the city’s goal.