Drinking Water Update - Oct. 16
There are two things we want you to know about your water from Forsyth County.
1) It is safe to drink.
2) We are continually testing and monitoring to ensure the safety of the water.
Here is an update on the unusual taste and odor.
Forsyth County Water and Sewer Department is aware that some residents are experiencing an unusual taste and odor with their water. Testing of the raw water from Lake Lanier has confirmed that levels of Methylisoborneol (MIB) and Geosmin are higher than have been seen in past years.
What are Geosmin and MIB?
Both Geosmin and MIB are naturally occurring compounds found in surface waters, such as Lake Lanier. They are organic molecules produced by algae. This year the levels in Lake Lanier started to rise in early August but appear to be dropping in early October.
Why is it happening now?
The presence of Geosmin and MIB typically happens during late summer into early fall. Bright sun, warm temperatures and nutrients result in ideal growing conditions for the algae. The compounds are produced inside the algae cells and are only released when the algae die.
Is my water safe?
Yes. These two compounds (Geosmin and MIB) are not harmful. However, they do affect the aesthetics of the water, specifically taste and odor.
The odor is similar to that found in overturned rich soils, and is present in some foods such as beets, spinach and mushrooms. While some people may notice this odor, others will not.
The levels of MIB and Geosmin are parts per trillion. For comparison, that is equivalent to about one minute in 1,900,000 years.
More than 1,300 tests are conducted annually by the Environmental Protection Division (EPD) of the Georgia Department of Natural Resources and Forsyth County to ensure you have safe drinking water.
These tests monitor tap water for organisms, mineral and organic substances that could cause disease or other adverse health effects. Testing is done for over 100 different contaminants including bacteria, metals, nitrates and pesticides.
The water quality data shown in the
Water Quality Report lists regulated drinking water contaminants that are monitored during the calendar year of the report.
Why do I smell it?
The human nose is extremely sensitive to Geosmin. If you poured a teaspoon of Geosmin into the equivalent of 200 Olympic-sized swimming pools, some people would still be able to smell it.
Heating the water can increase the volatility of these compounds, which explains why the smell is more easily detected when you are in the shower or using heated water.
What is the County doing to remove these compounds?
The County is using a powdered activated carbon (PAC) system to reduce the levels of MIB and Geosmin in the water. While the levels of MIB and Geosmin have been reduced in the finished water (water that reaches a customer’s home), the powdered activated carbon does not remove all of it.
The water is tested on a regular basis. Even though the levels are very low, some individuals will still be able to detect them.
In addition, the county is in the process of adding Ozone disinfection to the drinking water process that will greatly improve our ability to treat and remove these compounds. We expect to complete this additional treatment process within 12 months.
How long will the taste and odor last?
As the weather conditions and the water quality in Lake Lanier change and the levels of these compounds in the raw water are reduced, these compounds will decrease until they again reach undetectable levels.