Jefferson Water Hardness & Quality Report (2026)

Jefferson, Louisiana, in Jefferson Parish — a Jefferson Parish unincorporated community adjacent to Metairie and Kenner in the west New Orleans metro suburbs — receives its water from the Jefferson Parish Water System, drawing from the Mississippi River through the southeast Louisiana distribution.

The hard 162 mg/L hardness and TDS of 426 mg/L reflect the Jefferson Parish Mississippi River supply's hard character — the Quaternary Gulf Coastal plain alluvium and Holocene Mississippi Delta sediment contribute calcareous and sulfate mineral content from the vast Mississippi River drainage of calcareous Midwest and Great Plains formations (compare Metairie LA: 159/418 in Jefferson Parish comparable; Kenner LA: 164/433 in Jefferson Parish comparable; Jefferson consistent hard from the same Jefferson Parish Mississippi River Quaternary alluvial supply). The Mississippi watershed at Jefferson Parish — Quaternary Gulf Coastal plain alluvium (slightly calcareous — primary hardness contributor), Holocene Mississippi Delta sediment (calcareous — secondary contributor), and Holocene Mississippi alluvium (calcareous — TDS contributor).

At 162 mg/L with TDS 426, Jefferson's water is hard — scale builds in appliances. Quarterly descaling is appropriate. The PFAS level of 13.7 ppt is very high — a certified filter with PFAS removal is strongly recommended — Jefferson Parish is one of the most PFAS-contaminated water systems in Louisiana due to industrial corridor sources along the Mississippi River. Review the Jefferson Parish Water Quality Report annually.