How hard is the water in Vermilion Parish, LA?
10.9 grains per gallon
A softener will pay its way here.
The median hardness measured in Vermilion Parish, LA is 186 mg/L as calcium carbonate, which is 10.9 gpg. That is very hard on the USGS scale. It comes from 41 samples at 39 sites between 1990 and 2024, drawn from groundwater wells, which is what most taps and private wells in the county draw on.
How much it varies here
Half the sites came in between 9.1 and 12.6 gpg. That spread crosses a decision line, so some homes here land on a different answer. A $10 test strip on your own tap settles it. Confidence in the county figure: high (how it is measured).
What to do next
At 10.9 gpg a softener pays its way here. Before you buy, check the quoted unit's grain capacity against the sizing table below, and ask whether it regenerates on demand, which uses less salt than a timer. Call your utility for its own report if you are on city water. Because Vermilion Parish straddles a decision line, check your own tap with a $10 test strip before you spend anything.
More on sizing a softener for your household.
From 4.1 to 40.2 gpg
The softest single sample on record in Vermilion Parish was 70.9 mg/L and the hardest 688 mg/L, a 10-fold gap. The top quarter of sites read above 12.6 gpg and the bottom quarter below 9.1 gpg.
Wells 10.9 gpg, rivers and lakes 10.3 gpg
41 groundwater samples from 39 wells put the median at 186 mg/L. 779 surface samples from 15 sites put it at 177 mg/L. In Vermilion Parish the wells come out 0.6 gpg harder. Groundwater sits in contact with rock for years and picks up calcium and magnesium as it goes, so wells usually read harder. The two sources are close, so the county figure should hold whichever one your tap is on.
What a softener would cost to run
For a household of 3, a 24,000-grain unit covers a week between regenerations. Expect about 237 lb of salt a year (6 bags of 40 lb, about $43), and roughly 2,346 gallons of regeneration water. Installed, most units run $1,000 to $4,500; spread over 15 years with salt, that is about $143 a year.
Sizing at 10.9 gpg
| People | Grains a day | Unit | Salt a year |
|---|---|---|---|
| 1 | 654 | 24,000 | 80 lb |
| 2 | 1,308 | 24,000 | 159 lb |
| 4 | 2,616 | 24,000 | 318 lb |
| 6 | 3,924 | 32,000 | 477 lb |
Vermilion Parish against the rest of Louisiana
Among the 64 Louisiana counties with data, Vermilion Parish is number 23 of 64 counting from the hardest. Across the whole country it is harder than 54% of counties.
Softest in Louisiana: Lincoln Parish at 0.1 gpg. Hardest: St. Bernard Parish at 53.9 gpg. Closest to Vermilion Parish: Jefferson Parish (10.5), Caldwell Parish (11.2), St. Charles Parish (11.4).