Hardest Water in Louisiana
15 cities ranked by water hardness. Thibodaux tops the list at 180 PPM.
Louisiana's water hardness varies significantly by city and water source. The state average across our database is 81 PPM, which is moderately hard. Some cities need treatment while others do not. 7% of cities we track in Louisiana have hardness above 120 PPM.
Thibodaux has the hardest water at 180 PPM (10.5 GPG). At this level, expect visible scale on faucets, reduced water heater efficiency, and higher soap usage. A salt-based water softener typically pays for itself within 12-18 months in energy and consumable savings. Monroe has the softest water at just 40 PPM. No softener is needed.
| # | City | PPM | GPG | Level | Softener? |
|---|---|---|---|---|---|
| 1 | Thibodaux | 180 | 10.5 | Very Hard | Yes |
| 2 | Lafayette South | 100 | 5.8 | Moderately Hard | Optional |
| 3 | Baton Rouge | 86 | 5 | Moderately Hard | Optional |
| 4 | Kenner | 85 | 5 | Moderately Hard | Optional |
| 5 | Marrero | 85 | 5 | Moderately Hard | Optional |
| 6 | New Orleans | 80 | 4.7 | Moderately Hard | Optional |
| 7 | Metairie | 80 | 4.7 | Moderately Hard | Optional |
| 8 | Shreveport | 79 | 4.6 | Moderately Hard | Optional |
| 9 | Houma | 75 | 4.4 | Moderately Hard | Optional |
| 10 | Lake Charles | 70 | 4.1 | Moderately Hard | Optional |
| 11 | Lafayette | 65 | 3.8 | Moderately Hard | Optional |
| 12 | New Orleans Downtown | 65 | 3.8 | Moderately Hard | Optional |
| 13 | Slidell | 60 | 3.5 | Moderately Hard | Optional |
| 14 | New Orleans Uptown | 60 | 3.5 | Moderately Hard | Optional |
| 15 | Monroe | 40 | 2.3 | Slightly Hard | No |
Frequently Asked Questions
What is the average water hardness in Louisiana?
Across 15 cities in our database, the average water hardness in Louisiana is 81 PPM (4.7 GPG). This ranges from 40 PPM in Monroe to 180 PPM in Thibodaux.
Do I need a water softener in Louisiana?
It depends on your city. 7% of Louisiana cities in our database (1 of 15) have hardness above 120 PPM where a softener provides measurable benefit. Check your specific city above.
Which Louisiana city has the softest water?
Monroe has the softest water in Louisiana at 40 PPM (2.3 GPG). No water softener is needed at this level.
What causes hard water in Louisiana?
Hard water in Louisiana is caused by dissolved calcium and magnesium from the local geology. Regional geology varies, with some areas having limestone bedrock that adds minerals and others with granite or sandstone that produces softer water.