Understanding the Problem
What Are Disinfection Byproducts (TTHMs and HAA5) in North Georgia Water?
By Grant, Honest Water of Georgia · Published 2026-06-06 · 7 min read
If you have read your city's water quality report and seen terms like TTHMs, HAA5, or chloroform, those are disinfection byproducts.
They show up across nearly every North Georgia utility, and they are worth understanding without panic.
What they are
Public water has to be disinfected. Untreated surface water carries real risks, so utilities add chlorine to kill bacteria and viruses.
That step is necessary and protective.
The trade-off is that chlorine reacts with naturally occurring organic matter in the source water, and that reaction forms disinfection byproducts (DBPs).
The main families you will see on a report:
Total trihalomethanes (TTHMs), including chloroform and bromodichloromethane
Haloacetic acids (HAA5 and HAA9), including dichloroacetic and trichloroacetic acid
These are not "dirty pipes." They form during treatment itself, which is why even a well-run utility reports them.
Why North Georgia sees them
North Georgia draws heavily from surface water, mainly Lake Lanier and the Chattahoochee River.
Surface water carries more organic matter than deep groundwater, and more organic matter means more material for chlorine to react with.
That is the core reason DBPs are a recurring theme in local water reports.
Want to know what your own city's water report shows? Start with your city water guide, then we can help. Get an instant quote.
"Meets federal standards" is not the whole story
Here is the part that confuses people.
Your utility can truthfully say the water meets federal and state standards, and EWG can still report DBPs above its health guidelines, both at the same time.
The reason is that federal legal limits and EWG's health-based guidelines are different yardsticks. As EWG notes, passing federal standards does not necessarily mean water meets the latest health guidelines, in part because some legal limits have not been updated in close to two decades.
So "legal" and "ideal" are not the same thing.
What you do with that gap is a personal decision. Our job is to explain it honestly, not to scare you.
How homeowners reduce DBPs
If you want to reduce disinfection byproducts in your home's water:
Carbon filtration (often whole-home) reduces chlorine and some DBPs and improves taste and smell.
Reverse osmosis at the kitchen sink removes DBPs thoroughly from your drinking and cooking water. RO is the more complete option for what you actually consume.
A water softener does not address DBPs, since its job is hardness. That is why a complete setup for North Georgia water usually pairs softening with filtration.
See water softener vs water filter for the distinction.
What to do next
Look up your specific city.
Each North Georgia community has its own source water and its own reported levels, which is why our city water guides break the numbers down one community at a time.
Start there, then decide whether reducing DBPs is something you want to act on.
Frequently Asked Questions
Are disinfection byproducts dangerous?
We do not make health claims. What we can say is that EWG reports several DBPs above its health-based guidelines in many North Georgia utilities, and that some studies have linked long-term DBP exposure to health concerns. Water can meet federal standards and still exceed those stricter guidelines. Whether to reduce them is your call.
Why does the water get treated with chlorine at all?
Because disinfection is necessary. Untreated surface water carries serious risks from bacteria and viruses. DBPs are an unwanted byproduct of a step that protects public health.
Does boiling water remove disinfection byproducts?
Not reliably. Boiling can drive off some volatile compounds but is not a dependable way to remove DBPs, and it can concentrate others. Carbon filtration and reverse osmosis are the standard methods.
What removes TTHMs and HAA5 best?
Reverse osmosis removes them thoroughly from drinking water. Whole-home carbon reduces chlorine and some DBPs across all your water. A softener does not affect them.