Slidell, LA vs Jefferson, LA

When comparing tap water quality between Slidell, LA and Jefferson, LA, Jefferson currently holds a substantial 31-point lead in average WaterQ score, with a score of 96 out of 100 versus 65 for Slidell. Slidell, LA carries a C grade while Jefferson, LA carries an A. A WaterQ score reflects an aggregate of EPA-reported violations, monitoring data, and compliance history across all public water systems serving each city, so a higher score generally indicates fewer recent violations and a stronger compliance record, though it does not guarantee that every tap in the city tests identically.

Jefferson, LA is the larger of the two, with 369,089 more residents than Slidell, yet both cities are served by the same number of public water systems (2). This means the difference in population is handled by systems of different scale rather than a different count of utilities — larger systems generally serve more connections and may have more monitoring requirements under the Safe Drinking Water Act.

For residents of either Slidell or Jefferson, the most useful next step is to look up the specific water system that serves your address, since city-wide averages combine results from every system in the area. Visit the Slidell or Jefferson city pages below for a breakdown of local systems, recent violations, and contaminant-specific data, or browse WaterQ's contaminants directory to learn what each measured substance means for health.