Cahaba Water Co.
Shelby County water is moderately hard — and the number is published.
Two treatment plants on the Coosa basin, and total hardness reported at 86 and 95 ppm — about 5.0 and 5.6 grains per gallon. That lands in the moderately hard band, and it sits below the point where a softener usually starts paying for itself. Which is not what most people here get told.
The numbers.
Shelby County Water Services, PWSID AL0001671, is a surface-water system. Its two plants are reported separately, which is why most rows below carry two figures rather than one.
| What | Shelby County publishes | Central Alabama Water, for comparison | Limit |
|---|---|---|---|
| Total hardness | 86 and 95 ppm · 5.0 and 5.6 gpg | 38–224 mg/L · 2.2–13.1 gpg | No limit — aesthetic |
| Calcium | 23.5 and 26.7 ppm | 11.1 – 51.8 mg/L | — |
| Magnesium | 6.74 and 6.77 ppm | 1.76 – 9.42 mg/L | — |
| Trihalomethanes (TTHM) | 17.0 – 54.0 ppb at one plant 17.8 – 22.5 at the other | 11.4 – 26.0 ppb | 80 ppb |
| Chlorine | 2.22 and 2.47 ppm | 1.47 – 2.85 ppm | 4.0 ppm MRDL |
| Total dissolved solids | 88 and 100 ppm | 27.5 – 388 mg/L | 500 ppm |
| Lead, 90th percentile | 0.002 ppm | 0.003 mg/L | 0.015 ppm action level |
| Copper, 90th percentile | 0.04 ppm | 0.100 mg/L | 1.3 ppm action level |
Shelby County figures from the Shelby County Water Services 2023 Consumer Confidence Report. Central Alabama Water figures from its 2026 Annual Water Quality Report covering 2025 data. The report lists both plants in parallel columns; we publish the pair rather than assigning a figure to a named plant, because the report's column order is not unambiguous and we would rather print two true numbers than one confident guess. Every figure is inside its limit.
The byproduct row deserves a second look. At a high of 54.0 ppb, trihalomethanes here are the highest of any utility report we hold for this metro — roughly double Central Alabama Water's high, and several times the groundwater systems at Trussville and Leeds. It is comfortably inside the limit of 80 and the water is compliant. It is also the one number on this page that points clearly at carbon rather than at salt.
This is a carbon conversation, not a softener one.
On most systems in this metro we start by asking whether softening is justified. Here the published figures answer that fairly clearly, and point somewhere else.
- 5.0 to 5.6 grains is below the line where softening pays. Softening generally starts delivering noticeable improvement in soap performance, spotting and appliance life above about 7 grains. Shelby County publishes below that at both plants. If someone has quoted you a softener on this system, ask them which number they were working from.
- The byproducts are the thing that is actually elevated here. A high of 54.0 ppb against a limit of 80 is compliant, and it is also roughly double what Central Alabama Water publishes. Activated carbon reduces chlorine and its byproducts, and on this system that is where the money does the most work.
- Reverse osmosis at the tap is the straightforward answer for drinking water. It works on any potable city water, needs no test to specify, and the price is published.
- You still need your own number before anyone fits a softener. 86 and 95 ppm are plant figures. What arrives at your tap has travelled through the distribution system and your own plumbing. We mail a free test rather than assume.
Worth knowing if you are in Alabaster: the 86 and 95 ppm figures are the same water. The Alabaster Water Department buys surface water from this system, which is why those two numbers appear in its report too, alongside the much harder figure from its own wells. The Alabaster page covers that split.
Shelby County water, answered.
Who does Shelby County Water Services serve?
Retail customers across Shelby County, including Chelsea and the Greystone area, plus a number of other subdivisions. It also sells wholesale to other systems, including the Alabaster Water Department.
If you live in Hoover, this matters: the City of Hoover publishes that Greystone, excluding Greystone Highlands, is served by the Shelby County Water System rather than by Central Alabama Water. Hoover is split four ways, and that page covers it.
How hard is Shelby County water?
The utility publishes total hardness of 86 and 95 ppm from its two treatment plants. That is about 5.0 and 5.6 grains per gallon, which falls in the moderately hard band on the standard classification — between 3.5 and 7 grains.
For comparison, Central Alabama Water publishes a system range of about 2.2 to 13.1 grains, and Trussville publishes 8.9. Shelby County sits in the middle and, unusually for this metro, publishes a narrow pair of figures rather than a wide range.
Do I need a water softener on Shelby County water?
Probably not, on the published figures. Softening generally starts earning its cost above about 7 grains per gallon, and both plants report below that. We would rather tell you that than sell you one.
The caveat is that 86 and 95 ppm are figures at the plant. We still mail a free test so you have a number from your own tap before anyone makes a recommendation.
Why are the disinfection byproducts higher here?
Trihalomethanes form when chlorine meets organic matter, and surface water carries more of it than groundwater does. Shelby County reports a high of 54.0 ppb at one plant against a limit of 80. Central Alabama Water, also surface water, reports 11.4 to 26.0. The groundwater systems in the metro — Trussville and Leeds — report non-detect to 10.4.
All of those are compliant. Activated carbon reduces chlorine and its byproducts, which is why on this system carbon tends to be the more useful investment.
Do you serve the Shelby County Water area?
Yes — Chelsea, Greystone, Columbiana and the surrounding Shelby County area are all inside our everyday service ring. Under-sink reverse osmosis, whole-home treatment, and ongoing filter service. Installation is performed by an Alabama-licensed plumbing contractor. Our full service area is here.
Get the number from your own tap
The published figures say softening probably is not your priority on this system. A free mailed test confirms it for your address, and nobody comes to the house.