City water · Whole-home
Whole-home filtration for city water: carbon at the point of entry
What a whole-home filter is
A point-of-entry (POE) system treats water once, right after the main shutoff, so everything downstream gets the same water: kitchen, bathrooms, laundry and showers. On city water a typical setup has two parts. A sediment filter catches grit and particles so they don't clog what comes next. A carbon stage adsorbs the disinfectant and the tastes and odors that come with it. Carbon works by adsorption: dissolved substances stick to the surface and pores of the media as water passes through.[source]
Chlorine or chloramine: find out first
Utilities keep a disinfectant in the water all the way to your tap, and there are two common kinds. Free chlorine is what Charlotte Water uses; its 2025 residual averaged 1.04 ppm.[source] Chloramine, formed when ammonia is added to chlorine, lasts longer in the pipes.[source] Around Charlotte, the 2025 reports show:
- Chloramine: City of Monroe[source], Lancaster County Water & Sewer District[source], Chester Metropolitan District[source] and Columbia Water.[source]
- Both listed: Union County Water's report lists both chloramines and chlorine residuals and doesn't say which areas get which.[source]
- Free chlorine: Charlotte Water[source], Concord[source], Gastonia (Two Rivers Utilities)[source] and Mooresville[source], among others.
This matters because chloramine is harder for ordinary carbon to break down. NSF lists Chlorine Reduction and Chloramine Reduction as separate claims under NSF/ANSI 42, so a filter certified for one isn't automatically certified for the other.[source] Systems built for chloramine usually use catalytic (surface-modified) carbon and a larger media bed. Our chlorine taste and odor page goes deeper on the difference.
Certifications to look for
- NSF/ANSI 42 covers aesthetic claims such as chlorine, taste and odor, and applies to both point-of-use and whole-house systems.[source] Check that the model's listing includes the claim for your utility's disinfectant.[source]
- NSF/ANSI 53 covers contaminants with a health effect, such as lead or certain VOCs.[source] Fewer whole-house systems carry these claims; for lead or PFAS, a certified kitchen-tap RO system is usually the more practical tool.
- Look up the exact model in the NSF certified-product listings before buying.[source]
What it does, and what it doesn't
| Goal | Whole-home carbon? | Better tool, if not |
|---|---|---|
| Chlorine smell in showers and every tap | Yes, with the right carbon for your disinfectant | — |
| Grit or particles | Yes, the sediment stage | — |
| Hardness or scale | No | A softener, only if a test shows hardness; see the softener decision page |
| Lead from your own plumbing | Usually not; lead often comes from fixtures after the filter | Certified point-of-use filter or RO |
| PFOA / PFOS | Only if the specific system is certified for them | Certified point-of-use RO or carbon |
| Bacteria | No; carbon isn't a disinfection device | Not normally needed on disinfected city water |
One honest trade-off: once the disinfectant is removed at the entry, the water sitting in your home's pipes and water heater no longer carries a residual. Most households never notice a difference, but it's a reason not to oversize carbon you don't need, and to keep up with changes.
Installation
A whole-home system is cut into the main line near where it enters the house, often with a bypass valve so you can service it without shutting off water. It needs floor or wall space and, for some backwashing designs, a drain. That's licensed plumbing work in both Carolinas; here's how installation is handled.
Maintenance
Sediment cartridges are the frequent change; how often depends on how much grit your water carries. Carbon media lasts longer but has a finite capacity, and chloramine-rated beds are sized for it. Replace on the manufacturer's schedule, not when you finally smell chlorine again. A Care Plan tracks those dates for you.
Questions we hear
Does Charlotte Water use chloramine?
No. Charlotte Water's 2025 report lists free chlorine as its disinfectant. Monroe, Lancaster County W&SD, Chester and Columbia report chloramine, and Union County Water lists both.
Will a whole-house filter make my water soft?
No. Carbon doesn't remove hardness minerals. Most local city water is already soft; check the city-water softener page for your utility's number.
Do I need whole-home filtration and an RO?
Only if you want both outcomes. Whole-home carbon handles taste and smell everywhere; kitchen-tap RO is the tool for drinking-water goals like PFAS or lead. Many homes need one or neither.
Is a shower filter enough?
For one shower, possibly. NSF/ANSI 177 shower filters are certified only to reduce free available chlorine,[source] so they're not designed for chloramine.
Where we serve
Start with an honest answer about your water.
Tell us about your home and water source. We'll recommend testing first, and only the equipment your results support.