Skip to main content
WaterVerge

Water quality report · updated Jul 2026

Is Napoleonville, LA Tap Water Safe to Drink?

Graded A- — but Chlorate was detected above EPA limits. Here's what's in the water and how to remove it. What to do ↓

1 contaminant over a legal limit
2.0 ppb lead, 90th percentile · low
5 unresolved violations
21K people served by 1 water system

PWSID LA1007001 · high data confidence · local government utility

Reviewed by WaterVerge Editorial Team · Last updated July 2026
A 85 / 100

#69 of 309Louisiana cities
How we grade →

01The verdict: is Napoleonville water safe?

Napoleonville's drinking water has significant quality concerns based on EPA testing data. With a grade of A- (85/100), the system has issues across multiple categories. A water filter is recommended for all residents. The city's 1 water system serves approximately 21,366 residents using surface water (rivers, lakes, or reservoirs).

The concern

Chlorate is over its legal limit

Measured at 500.0 µg/L against the EPA Lifetime HA of 210 µg/L. The ledger below shows how far over — and which filter removes it.

See the measurement ↓
The good news

Lead is well under the limit

90th-percentile lead is 2.0 ppb — beneath the 15 ppb federal action level and under the 5 ppb watch threshold.

See the trend ↓
Keep watching

lithium is approaching its limit

Measured at 15.7000 µg/L — 120% of the 0.004 µg/L limit. Within the rules, but with less headroom than you'd want.

See the ledger ↓

Napoleonville's drinking water received a grade of A- (85 out of 100), indicating good water quality. The city's 1 water system serves approximately 21,366 residents using surface water.

Lead levels were measured at 2.0 ppb (90th percentile), well within EPA limits. UCMR 5 testing detected 3 PFAS compounds in the water supply. The system has 33 violations on record, including 27 health-based violations. 5 remain unresolved.

Napoleonville ranks #69 out of 309 cities in Louisiana for water quality, placing it above average in the state. The city draws from surface water sources, which are more susceptible to seasonal runoff and agricultural contamination, requiring extensive multi-barrier treatment including coagulation, filtration, and disinfection. PFAS compounds were detected in testing, though levels remain within current EPA limits. Residents seeking extra precaution may consider an activated carbon or reverse osmosis filter. Haloacetic acid (HAA5) levels were elevated at 44.8 µg/L in UCMR 4 testing, though below the 60 µg/L EPA limit. Activated carbon filtration can help reduce these disinfection byproducts. Hexavalent chromium (chromium-6) was detected at 0.08 µg/L in UCMR 3 testing. While below California's 10 µg/L limit and with no federal MCL set, residents sensitive to this contaminant may consider reverse osmosis filtration.

How the 85/100 breaks down Methodology →
ViolationsHistorical violation record including health-based and monitoring violations.
37.6 / 45B
Lead & CopperLead at 2.0 ppb (90th percentile).
20 / 20A
Contaminants3 PFAS compounds detected.
15.4 / 20B
ComplianceMonitoring and reporting compliance with EPA regulations.
8 / 10B
Source RiskWater source: Surface water.
4 / 5B

02What's in Napoleonville's water

Every contaminant flagged in Napoleonville, on one shared scale: distance to its own legal limit. The red line is the limit — anything past it is out of compliance, and the closer a bar gets, the less headroom the system has.

10 detections · sorted by % of legal limit
Over the limit Elevated — watch Within limits
0 50% LEGAL LIMIT 150%
lithium PFAS / Forever Chemical
15.7000 µg/L 120% of limit
Chlorate Disinfection Byproduct
500.0 µg/L 120% of limit
1,4-Dioxane Organic
0.12 µg/L 34% of limit
Lithium Inorganic
15.7 µg/L 26% of limit
Strontium Inorganic
186.0 µg/L 12% of limit
Vanadium Inorganic
2.00 µg/L 10% of limit
Molybdenum Inorganic
1.80 µg/L 5% of limit
39 contaminants tested under EPA SDWIS, LCR and UCMR programs · 12 detected Contaminants without a federal MCL are shown against the strictest state or advisory level named in each row.

Full contaminants report

Contaminant Detected Level EPA Limit Unit Category Status
Lead (90th percentile) 2.0 15 ppb Inorganic Safe
11Cl-PF3OUdS ND HI µg/L PFAS Not Detected
4:2 FTS ND HI µg/L PFAS Not Detected
6:2 FTS 0.015 HI µg/L PFAS Detected
8:2 FTS ND HI µg/L PFAS Not Detected
9Cl-PF3ONS ND HI µg/L PFAS Not Detected
ADONA ND HI µg/L PFAS Not Detected
HFPO-DA ND 0.01 µg/L PFAS Not Detected
lithium 15.700 HI µg/L PFAS Detected
NEtFOSAA ND HI µg/L PFAS Not Detected
NFDHA ND HI µg/L PFAS Not Detected
NMeFOSAA ND HI µg/L PFAS Not Detected
PFBA 0.006 HI µg/L PFAS Detected
PFBS ND HI µg/L PFAS Not Detected
PFDA ND HI µg/L PFAS Not Detected
PFDoA ND HI µg/L PFAS Not Detected
PFEESA ND HI µg/L PFAS Not Detected
PFHpA ND HI µg/L PFAS Not Detected
PFHpS ND HI µg/L PFAS Not Detected
PFHxA ND HI µg/L PFAS Not Detected
PFHxS ND HI µg/L PFAS Not Detected
PFMBA ND HI µg/L PFAS Not Detected
PFMPA ND HI µg/L PFAS Not Detected
PFNA ND HI µg/L PFAS Not Detected
PFOA ND 0.004 µg/L PFAS Not Detected
PFOS ND 0.004 µg/L PFAS Not Detected
PFPeA ND HI µg/L PFAS Not Detected
PFPeS ND HI µg/L PFAS Not Detected
PFTA ND HI µg/L PFAS Not Detected
PFTrDA ND HI µg/L PFAS Not Detected
PFUnA ND HI µg/L PFAS Not Detected
Data source: EPA SDWIS, UCMR 5, local utility CCR.

03Napoleonville's ten-year track record

Each box is one year. A green check means no EPA violations; a numbered badge counts that year's violations — red if any were health-based, amber if they were monitoring or paperwork issues. The system has 33 violations on record, including 27 health-based violations. 5 remain unresolved.

8 of the last ten years were clean. The numbered years had EPA violations — red when any were health-based, amber when they were paperwork or missed-testing issues.

2 health-based in 10 yrs 1 monitoring & paperwork
PFAS3 PFAS "forever chemical" compounds detectedDetected at levels within current EPA limits. PFAS persist indefinitely in the environment.
UpdateWater quality data updatedLatest EPA compliance and testing data incorporated into Napoleonville's water quality assessment. Grade: A- (85/100).
Violation1 drinking water violation recorded1 health-based. Contaminants: Total Haloacetic Acids (HAA5).Resolved
Violation1 drinking water violation recorded1 health-based. Contaminants: Total Haloacetic Acids (HAA5).Resolved
Violation1 drinking water violation recordedContaminants: Revised Total Coliform Rule.Resolved
Lead, 90th percentileppb · lower is better
0102030EPA action level · 15 ppb1992 — 4 ppb1993 — 1 ppb2001 — 1 ppb2004 — 22 ppb2007 — 2 ppb2008 — 2 ppb2011 — 2 ppb2014 — 2 ppb2017 — 2 ppb2020 — 0 ppb2023 — 2 ppb4219922004201120202023

Down 2 ppb since 1992. Latest reading: 2 ppb (2023) — 13% of the action level. Sampled at higher-risk homes (90th percentile).

04Where Napoleonville's water comes from

Napoleonville's drinking water comes primarily from surface water sources such as rivers, lakes, or reservoirs.

Source

Surface Water

Rivers, lakes, or reservoirs — more exposed to runoff, agriculture, and seasonal swings than groundwater.

Treatment

Local treatment

Multi-barrier treatment: coagulation, sedimentation, filtration, and disinfection to meet EPA standards.

Distribution

1 system

1 water system (1 wholesaler), operated under local government ownership.

Delivery

21,366 people

Residents served across Napoleonville's service area.

Surface water systems require multi-stage treatment including coagulation, sedimentation, filtration, and disinfection to meet EPA Safe Drinking Water Act standards. These sources can be impacted by seasonal changes, stormwater runoff, upstream agriculture, and industrial discharge. The system is operated by local government ownership and serves approximately 21,366 people through 1 water system.

System namePWSIDPopulationSource
ASSUMPTION PARISH WW DISTRICT 1 LA1007001 21,366 Surface Water

Water bodies near Napoleonville

Bayou Lafourche At Napoleonville · river

As a surface-water system, these water bodies may directly influence Napoleonville's drinking water supply.

05Pressure on Napoleonville's watershed

Outside forces that shape what reaches the treatment plant. None of these is a verdict on the tap by itself — but each adds pressure worth knowing about.

Industrial discharge

Present — monitored

3 facilities within 10 miles reported 0 lb released to surface water in the latest EPA Toxics Release Inventory. Proximity doesn't equal tap contamination — treatment and hydrology decide — but it's pressure on the watershed.

KOCH METHANOL ST. JAMES LLC 0 lb · 9.8 mi
ENTERPRISE PRODUCTS OPERATING 0 lb · 6.8 mi
THE DOW CHEMICAL CO GRAND BAYOU OPERATIONS 0 lb · 4.9 mi

06How Napoleonville compares

Scores for nearby Louisiana cities on one line, with the average marked.

Jefferson
85.8 · A-
Napoleonville (this city)
85 · A-
Baton Rouge
43.2 · F
Shreveport
36.5 · F
Lafayette
35.1 · F
New Orleans
34.1 · F

dashed line = Louisiana average (53/100)

Napoleonville scores 85/100above the Louisiana average of 53/100. It outscores 9 of 10 nearby cities. Full Louisiana rankings →

Assumption Parish water quality rankings
Compare all cities in the county — grades, violations, and contaminant data side by side.

07What to do at home

Steps matched to what testing actually found in Napoleonville's water — not generic advice.

Because of pfas

Filter drinking & cooking water

Activated carbon or reverse osmosis filter. 3 PFAS compounds detected

Compare tested filters →
Know your report

Read your utility's annual report

Every utility must publish a yearly Consumer Confidence Report with its own testing results. It pairs well with the independent data on this page.

How to read a CCR →
Stay informed

Watch for Napoleonville alerts

We refresh EPA data monthly and surface new violations, advisories, and boil-water notices for your county on this page.

All water alerts →

Frequently asked questions

Is Napoleonville, LA tap water safe to drink?

Napoleonville's water quality earned a grade of A- (85/100). The water generally meets EPA standards and is considered safe for consumption. The city ranks #69 out of 309 cities tested in Louisiana.

What contaminants are in Napoleonville's water?

Lead was measured at 2.0 ppb (90th percentile). 3 PFAS compounds were detected. 33 violations are on record.

How is Napoleonville's water quality grade calculated?

The grade is based on four factors: violation history (40%), lead and copper levels (25%), PFAS contamination (25%), and regulatory compliance (10%). The score is also adjusted based on how complete the available data is. See our methodology page for full details.

Do I need a water filter in Napoleonville?

PFAS compounds have been detected. A filter with activated carbon can help reduce exposure.

Where does Napoleonville's water come from?

Napoleonville's water is sourced from Surface water. The city has 1 water system serving approximately 21,366 residents.

What health violations has Napoleonville's water system had?

Napoleonville has 27 health-based violations on record. The most recent violation was recorded in October 2019. Health-based violations mean the water exceeded EPA maximum contaminant levels (MCLs) for a regulated substance. 5 violations remain unresolved.

Why does Napoleonville have so many PFAS compounds in its water?

3 different PFAS "forever chemical" compounds were detected in Napoleonville's water supply during UCMR 5 testing. PFAS contamination often originates from proximity to military installations (AFFF firefighting foam), airports, industrial manufacturing sites, or wastewater treatment facilities. While detected, current levels are within EPA limits. An activated carbon filter can further reduce exposure.

How does Napoleonville's water compare to other cities?

Napoleonville ranks #69 out of 309 cities in Louisiana (better than 78% of state cities) and #5502 out of 15382 cities nationally (64th percentile). The grade of A- reflects the combined assessment of violation history, lead and copper levels, PFAS contamination, and regulatory compliance.

Share this reportHelp others learn about their water quality
WhatsAppXFacebookLinkedInEmail
About Napoleonville, LA: Median household income $19,189 · median age 35.8 · 42% homeowners · 0.8% college educated. Service area: 1 ZIP code across Assumption Parish.
Show ZIP codes 70390
Sources: EPA SDWIS & ECHO · UCMR 3–5 · Lead & Copper Rule samples · EPA TRI · U.S. Drought Monitor · FEMA declarations. Data last updated Jul 2026. Analysis by the WaterVerge Editorial Team · methodology.