Chalmette Water Hardness & Quality Report (2026)

Chalmette, Louisiana, in Saint Bernard Parish — the Saint Bernard Parish seat adjacent to Meraux and Violet on the lower Mississippi River east of New Orleans, site of the Battle of New Orleans — receives its municipal water from Saint Bernard Parish Utilities, drawing from the Mississippi River at the Chalmette treatment plant (Saint Bernard Parish, southeast Louisiana).

The moderately soft 72.5 mg/L hardness and low TDS of 132.9 mg/L are lower than typical Mississippi River hardness (upstream Missouri-Iowa: 200-300+ mg/L), reflecting the dilution effect of the lower Mississippi below the major tributary confluences. By the time the Mississippi reaches southeast Louisiana, the Ohio River and Missouri River carbonate loading has been diluted by the vast drainage basin volume, and the Quaternary siliceous alluvial sand of the Mississippi deltaic plain contributes minimal additional hardness. The lower Mississippi's naturally soft delta supply produces the moderately soft Chalmette reading.

At 72.5 mg/L, Chalmette's water is moderately soft — light scale forms slowly in appliances, dishwashers remain efficient, and bathroom fixtures need occasional cleaning. Semi-annual descaling is appropriate. The PFAS level of 7.7 ppt warrants a certified drinking water filter — the Saint Bernard Parish industrial corridor (Chalmette Refinery complex — one of the most PFAS-contaminated refinery areas in Louisiana), and the lower Mississippi River PFAS legacy from upstream industrial discharges contribute to Chalmette's elevated readings.