State distribution
Hardness across indexed ZIPs
Counts describe published ZIP profiles, not a population-weighted statewide sample.
Soft · 0–60 PPM32
Moderately hard · 61–120 PPM9
Hard · 121–180 PPM25
Very hard · 181+ PPM7
State water index
Louisiana water hardness
Search 52 indexed communities and 102 ZIP profiles, then compare the underlying utility, source, distance, and reporting context.
Median regional evidence
98PPM
Moderately Hard
Indexed range 5–411 PPM
- ZIP profiles
- 102
- Cities
- 52
- Matched utilities
- 56
- Counties
- 34
Understanding Louisiana
Why local comparisons matter here
Louisiana combines Mississippi River and other surface-water systems with alluvial and coastal-plain aquifers. Source choices differ between major river cities and smaller groundwater systems.
In this index, soft is the largest category, covering 32 of 73 profiles with hardness data. The state median is 98 PPM, but the full indexed range is 5–411 PPM.
Evidence coverage
What the current records support
- Hardness estimate
- 72%
- Lead 90th percentile
- 100%
- Copper 90th percentile
- 12%
42
Low-confidence hardness profiles
21
Research-comparison eligible profiles
Reported source water
Utility source mix
- Groundwater
- 46
- Surface water
- 10
Highest medians
Highest eligible city medians
- 1. Shreveport133 PPM
- 2. Natchitoches30 PPM
Lowest medians
Lowest eligible city medians
- 1. Natchitoches30 PPM
- 2. Shreveport133 PPM
City directory
Explore Louisiana by city
Search by city or county, then sort by name, hardness, or ZIP coverage.
52 cities · 102 ZIP profiles
52 cities found
Page 1 of 3
Abbeville
Vermilion Parish · 1 ZIP
132PPM regional
Single regional valueNo active flag
Alexandria
Rapides Parish · 4 ZIPs
7PPM regional
Single regional valueNo active flag
Bastrop
Morehouse Parish · 1 ZIP
12PPM regional
Single regional valueNo active flag
Baton Rouge
East Baton Rouge Parish · 16 ZIPs
40PPM regional
Single regional valueNo active flag
Belmont
Sabine Parish · 1 ZIP
—
No regional sample1 active record
Berwick
St. Mary Parish · 1 ZIP
139PPM regional
Single regional valueNo active flag
Bogalusa
Washington Parish · 1 ZIP
—
No regional sample11 active records
Breaux Bridge
St. Martin Parish · 1 ZIP
119PPM regional
Single regional value1 active record
Broussard
Lafayette Parish · 1 ZIP
122PPM regional
Single regional valueNo active flag
Carencro
Lafayette Parish · 1 ZIP
125PPM regional
Single regional value1 active record
Covington
St. Tammany Parish · 2 ZIPs
—
No regional sample1 active record
Denham Springs
Livingston Parish · 1 ZIP
40PPM regional
Single regional valueNo active flag
Deridder
Beauregard Parish · 1 ZIP
11PPM regional
Single regional valueNo active flag
Egan
Acadia Parish · 1 ZIP
177PPM regional
Single regional value8 active records
Folsom
St. Tammany Parish · 1 ZIP
—
No regional sampleNo active flag
Franklin
St. Mary Parish · 1 ZIP
139PPM regional
Single regional value1 active record
Gonzales
Ascension Parish · 1 ZIP
40PPM regional
Single regional valueNo active flag
Gretna
Jefferson Parish · 1 ZIP
188PPM regional
Single regional valueNo active flag
Hammond
Tangipahoa Parish · 3 ZIPs
—
No regional sampleNo active flag
Houma
Terrebonne Parish · 2 ZIPs
—
No regional sampleNo active flag
Jennings
Jefferson Davis Parish · 1 ZIP
177PPM regional
Single regional value2 active records
Kaplan
Vermilion Parish · 1 ZIP
358PPM regional
Single regional valueNo active flag
Lake Charles
Calcasieu Parish · 5 ZIPs
98PPM regional
Regional range 98–130.5No active flag
Lake Providence
East Carroll Parish · 1 ZIP
411PPM regional
Single regional value17 active records
County comparison
Highest regional-evidence county medians
| County | Median | Range | ZIP profiles |
|---|---|---|---|
| East Carroll Parish | 411 PPM | 411–411 | 1 |
| Franklin Parish | 294 PPM | 294–294 | 1 |
| Vermilion Parish | 245 PPM | 132–358 | 2 |
| Jefferson Parish | 188 PPM | 187.5–187.5 | 1 |
| Jefferson Davis Parish | 177 PPM | 177–177 | 1 |
| Acadia Parish | 155 PPM | 132–177 | 2 |
| St. Mary Parish | 139 PPM | 138.5–138.5 | 3 |
| Caddo Parish | 133 PPM | 133–243 | 13 |
| Lafayette Parish | 125 PPM | 122–130 | 5 |
| De Soto Parish | 124 PPM | 124–124 | 1 |
| St. Martin Parish | 119 PPM | 119–119 | 1 |
| Richland Parish | 109 PPM | 109–109 | 2 |