Is Morrisville, NC Water Hard?

Triangle Waterworks · informational guide

Direct answer: It depends on your address. Morrisville receives Cary's treated water, and our own testing across Cary, Apex and Morrisville measures 1.6 to 3.7 grains per gallon depending on where the home sits. At 1.6 gpg that's slightly hard; at 3.7 gpg it's moderately hard on the Water Quality Association (WQA) scale — the same one the Hach Total Hardness Test Kit (Model 5-B) uses. Morrisville publishes no hardness figure of its own, so the only way to know yours is a test at your tap.

So is Morrisville water hard or soft?

Both ends of that answer are true for different Morrisville homes, and here's the honest version. On the WQA five-tier scale — the same one the Hach Total Hardness Test Kit (Model 5-B) uses — the line between slightly hard and moderately hard sits at 3.5 grains per gallon, or roughly 60 mg/L:

Triangle Waterworks measures 1.6 to 3.7 grains per gallon in homes across Cary, Apex and Morrisville. The bottom of that range — 1.6 gpg, about 27 mg/L — is slightly hard, one tier above soft. The top of it — 3.7 gpg, which works out to about 63 mg/L — is over the 3.5 gpg (60 mg/L) line and therefore moderately hard. The WQA scale runs five tiers from soft through very hard, so a Morrisville reading in this range lands in one of the first two bands depending on the address.

So the real answer to "is Morrisville water hard" is: it's slightly hard in some Morrisville homes and moderately hard in others, and you cannot tell which yours is from a published average.

Why can't I just look up Morrisville's hardness number?

Because Morrisville doesn't publish one — it doesn't run its own water system. The Town of Cary has operated Morrisville's water and sewer utility since April 2006, so Morrisville households receive Cary's finished water and there's no separate Morrisville figure to find. If your search came up empty, nothing is broken; the document simply doesn't exist.

The closest published numbers come from the two towns that own the plant:

• The Town of Cary publishes finished water hardness of 25 to 30 ppm, about 1.5–1.75 grains per gallon.
• The Town of Apex, in its 2024 annual water quality report, gives an average total hardness of 33.3 ppm, or 1.9 grains per gallon.

Both describe finished water leaving the Cary/Apex Water Treatment Facility — a 56 million-gallon-per-day plant drawing from B. Everett Jordan Lake, co-owned by Cary and Apex with Cary operating it. Those are plant-wide averages for water at the point it enters the distribution system, which is exactly what a utility should publish.

What we measure is a different point: the tap, after the water has traveled through mains and service lines to a specific house. That's why our range reaches 3.7 gpg while the plant averages sit lower. Neither figure contradicts the other — they're answers to different questions. The one that matters for your dishwasher is the one from your own address.

What does hardness at this level actually do in a Morrisville home?

It accumulates. This is the part people miss when they read a low average and assume there's nothing to manage. Calcium and magnesium are present at every level in that 1.6–3.7 gpg range, and every gallon that passes through the house leaves a little behind:

• Glassware and dishes come out with spots or a cloudy film that rinse aid masks but doesn't prevent.
• Faucet aerators and shower heads develop crusty white deposits that restrict spray patterns.
• Shower doors and tile accumulate soap scum, which is what forms when soap reacts with dissolved minerals instead of lathering.
• Soap and detergent go further in softened water, because less of each load is spent reacting with minerals.
• The water heater collects scale on the tank bottom and heating elements over years of daily use — the failure mode nobody sees until it's already happened.

None of that is dramatic in month one. All of it is cumulative across the ten or fifteen years you own the house, which is the timescale the equipment is actually protecting.

Is hardness the only thing Morrisville homeowners should treat?

No — and for this water system, it's arguably the second story. Morrisville's water carries a chloramine residual, formed by dosing chlorine and ammonia separately in the plant's clearwell, and the system switches to free chlorine once a year to flush the distribution mains, which is when households notice a chlorine taste. Apex's 2024 report for the shared system documents TTHM at 41 ppb, ranging up to 53, and HAA5 at 19 ppb — both compliant with EPA limits, and roughly double Raleigh's 21.7 ppb TTHM. It also detected PFBA at 3.8 ppt and PFHxA at 3.65 ppt, with PFOS, PFOA, PFHxS, PFNA and PFBS non-detect.

Softening does nothing about any of that. Ion exchange targets calcium and magnesium, full stop. Disinfection byproducts and disinfectant taste are activated carbon's job, which is precisely why the system we install in Morrisville homes combines both: softening resin plus an activated carbon stage in one whole-home unit — the best of both worlds, sized from your own test results.

What does it cost to handle this in Morrisville?

Locally installed all-in-one systems are sized and priced after a free water analysis, well under the $6,000 to $12,000 national big-brand installers commonly quote. Operating cost is where this area does genuinely well: because the water starts out low in hardness, the softening side regenerates infrequently and uses very little salt, so annual running cost stays small. Low hardness is a reason the system is cheap to own here — see our Morrisville water softener cost breakdown for the full numbers.

Find out where your Morrisville address falls

Take our 60-second water quiz to see which all-in-one system fits your home, or book a free water analysis — since Morrisville publishes no figure, a test at your tap is the only real answer.

Frequently Asked Questions

I keep finding different hardness numbers for Morrisville online — which one is right? Most of them are describing Cary's or Apex's plant averages, because Morrisville publishes nothing of its own. Those averages are accurate for water leaving the treatment plant; what reaches your tap varies by address across the 1.6–3.7 grain-per-gallon range we measure, so the reading at your house is the one that applies to you.

My dishwasher leaves white film on everything — does that mean my water is hard? It means minerals are drying on the glass, which happens across this entire range rather than only at the top of it. Water temperature, detergent type and rinse aid all affect how visible it gets, so a hardness reading at your tap is the quickest way to confirm the cause before changing anything else.

Does 3.7 grains per gallon really count as moderately hard? Yes. 3.7 gpg is about 63 mg/L, and the WQA slightly-hard/moderately-hard boundary sits at 3.5 gpg (60 mg/L), so a reading at the top of our measured range crosses that line. Readings at the bottom of the range sit in the slightly-hard tier.

Is Morrisville's water the same as Cary's? Yes — Cary has operated Morrisville's water and sewer utility since 2006, so Morrisville taps deliver Cary's treated Jordan Lake water from the plant Cary and Apex jointly own. Address-level hardness still varies within that shared system.

Will a softener help if my hardness comes back at the low end (slightly hard)? Yes, in two ways worth knowing about. Minerals still accumulate on fixtures and inside the water heater at any level in this range, and a softener running on low-hardness water regenerates rarely and uses very little salt — so protection is cheap here rather than expensive.

Related reading: Water Softener in Morrisville, NC | Who Installs Water Treatment in Morrisville, NC | How to Test Water Hardness at Home | Water Softener Salt Cost Per Year