Trihalomethanes and Haloacetic Acids in Morrisville, NC Water — Which Report Do You Read?

Triangle Waterworks · informational guide

Direct answer: Search for a Morrisville water quality report and you won't find one — the town publishes none. Cary has operated Morrisville's water and sewer utility since April 2006, so Cary's 2025 Consumer Confidence Report is the document that actually applies: TTHM at 37 ppb (up to 43) and HAA5 at 17 ppb (up to 17), both compliant. A carbon stage removes both from a Morrisville tap.

Why can't I find a water quality report for Morrisville, NC?

Because one doesn't exist. Type "Morrisville water quality report" or "Morrisville CCR" into a search bar and you'll come up empty, not because it's hard to find, but because Morrisville has never published its own — it doesn't operate its own treatment plant, so there's no Morrisville-specific document to publish in the first place.

That's a real gap for a Morrisville homeowner trying to look up their own numbers, and it's worth resolving directly rather than leaving unanswered.

So whose report is actually the right one to read?

Cary's. The Town of Cary has operated Morrisville's water and sewer utility since April 2006, which means Morrisville addresses receive Cary's finished water rather than water treated separately for the town. Cary's own current Consumer Confidence Report is the accurate stand-in for a Morrisville-specific report — not a rough approximation, but the actual document describing the water reaching a Morrisville tap.

That arrangement also explains the source. Cary draws from B. Everett Jordan Lake and treats it at the Cary/Apex Water Treatment Facility, a plant Cary operates as the lead agency in partnership with Apex. A Morrisville home is downstream of that same plant, on the same distribution system as Cary and Apex customers.

What does Cary's 2025 report show for TTHM and HAA5?

Cary's 2025 Consumer Confidence Report lists total trihalomethanes (TTHM) at an average of 37 ppb, with site readings running as high as 43 ppb. Haloacetic acids (HAA5) average 17 ppb, with a reported range running from 9 up to 17 ppb. Both figures sit under EPA's Maximum Contaminant Levels, and Cary reports no violations for either.

EPA's National Primary Drinking Water Regulations table lists the potential health effects of long-term exposure above the MCL: for TTHMs, "Liver, kidney or central nervous system problems; increased risk of cancer." For HAA5, "Increased risk of cancer." Cary's water is compliant on both counts, which means those effects describe exposure above the legal line, not the water currently reaching a Morrisville home. Still, that legal line marks the exposure EPA judged tolerable, not the point at which these compounds stop being present in the water.

Why does a lake-sourced system produce these compounds at all?

Because disinfecting the water requires it. Cary treats Jordan Lake water with chloramine to control bacteria, and that disinfectant reacts with organic material naturally present in lake water — decayed plant matter, algae — on its way through the plant and into the distribution system. TTHM and HAA5 are the byproduct of that reaction, not something added on purpose or a sign of a treatment problem.

A groundwater well doesn't carry the same organic load, which is one reason this specific issue is tied to surface-water systems like the one supplying Morrisville, rather than every water source.

Does Cary's report actually apply to what's coming out of a Morrisville faucet today?

Yes, with one caveat worth naming: Cary's figures are a system-wide average, and Morrisville sits at a particular point in that distribution network, not the plant gate. Site-level TTHM and HAA5 readings vary by location the further water travels from the treatment facility, which is part of why Cary's own reported range runs up to 43 ppb for TTHM rather than a single flat number.

That third row is the honest resolution to the search problem — Cary's report tells you what the system produces, and a reading at your own address tells you what's actually reaching your fixtures.

What removes TTHM and HAA5 from a Morrisville home's water?

Activated carbon. It's the standard method for pulling both compound groups out of tap water at the point of use — the compounds adsorb onto the carbon media as water passes through it. A water softener doesn't do this; softening is ion-exchange resin built for calcium and magnesium, with no mechanism for organic disinfection byproducts.

That's why an all-in-one whole-home system pairs a carbon stage with softening resin rather than installing just one or the other. The carbon side handles TTHM, HAA5, chlorine taste, and PFAS; the softening side protects the water heater, dishwasher, and plumbing from the mineral buildup that shows up separately from any of this.

Get a reading specific to your Morrisville address

Cary's 2025 CCR is the right document for a Morrisville home — but it's still a system average, not a reading from your own tap. Take the 60-second water quiz to see what fits your Morrisville home, or book a free water analysis and find out what's actually there — the fix is a free water analysis away, not another search for a report that doesn't exist.

FAQ

I've searched everywhere and can't find a Morrisville-specific water report — am I missing something? No, you're not missing anything — Morrisville genuinely doesn't publish one. Cary has run Morrisville's water and sewer utility since April 2006, so Cary's own current Consumer Confidence Report, showing TTHM up to 43 ppb and HAA5 up to 17 ppb, is the document that actually describes a Morrisville tap.

I just moved to Morrisville from a town with its own utility — why doesn't Morrisville run its own water system? Morrisville chose to have Cary operate its water and sewer utility rather than build and run a separate treatment system, an arrangement in place since April 2006. Practically, that means Morrisville addresses receive the same finished water Cary delivers to its own customers, from the same Cary/Apex Water Treatment Facility on Jordan Lake.

My neighbor's report shows different TTHM numbers than mine — how is that possible in the same area? Different towns in the Triangle sit on different utilities, with different source water and separate treatment plants, so their reports carry genuinely different figures. What matters for a Morrisville address is Cary's report, because Cary produces and delivers the water. Comparing your figures against a town on another system tells you very little about your own tap.

Does boiling my Morrisville tap water get rid of TTHM or HAA5 before I drink it? Boiling answers a different question — it's what you do about microbial contamination, not about water chemistry. For TTHM and HAA5 the established route is activated carbon, which is the stage a whole-home system adds alongside softening resin.

Is HAA9 the same thing as the HAA5 figure in Cary's report? No. HAA5 is the five-compound group EPA regulates with a 60 ppb legal limit, and it's what Cary's CCR reports. HAA9 is a broader nine-compound sum some independent databases track, with no EPA limit attached at all — never described as "compliant," since there's no legal ceiling for it to meet.

Would a whole-home softener installed at my Morrisville house also take care of TTHM and HAA5? No — a softener only handles calcium and magnesium through ion exchange, with nothing that touches TTHM or HAA5. An all-in-one system adds a separate activated carbon stage alongside the softening resin, so one installation covers both the hardness and the disinfection byproducts in Cary's report.

Sources

• Town of Cary — Water Quality Report
• EPA — National Primary Drinking Water Regulations

Related reading: Water Softener Morrisville NC | What Are TTHM and HAA5 Disinfection Byproducts in Triangle, NC Tap Water? | Is Morrisville, NC Water Hard? | How to Find a Water Treatment Company Near Me in Morrisville, NC