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WaterVerge

Water quality report · updated Jul 2026

Is Larchmont (V), NY Tap Water Safe to Drink?

Graded A-, with 3 unresolved violations on record. See what was cited — and what it means for your tap. What to do ↓

0 contaminants over a legal limit
4.9 ppb lead, 90th percentile · low
3 unresolved violations
6K people served by 1 water system

PWSID NY5903433 · high data confidence · local government utility

Reviewed by WaterVerge Editorial Team · Last updated July 2026
A 88.1 / 100

#322 of 810New York cities
How we grade →

01The verdict: is Larchmont (V) water safe?

Larchmont (V)'s drinking water has significant quality concerns based on EPA testing data. With a grade of A- (88.1/100), the system has issues across multiple categories. A water filter is recommended for all residents. The city's 1 water system serves approximately 6,485 residents using surface water (rivers, lakes, or reservoirs).

The concern

3 unresolved violations on record

EPA records show open compliance items for this system. Most are administrative, but unresolved items are worth watching.

See what was cited ↓
The good news

Lead is well under the limit

90th-percentile lead is 4.9 ppb — beneath the 15 ppb federal action level and under the 5 ppb watch threshold.

See the trend ↓
Keep watching

2 violations in the last five years

Recent compliance history is the best predictor of future problems — the year-by-year record is below.

See the record ↓

Larchmont (V)'s drinking water received a grade of A- (88.1 out of 100), indicating good water quality. The city's 1 water system serves approximately 6,485 residents using purchased surface water.

Lead levels were measured at 4.9 ppb (90th percentile), well within EPA limits. PFAS testing under UCMR 5 found no detectable forever chemicals. The system has 5 violations on record, including 0 health-based violations. 3 remain unresolved.

Larchmont (V) ranks #322 out of 810 cities in New York for water quality, placing it mid-range 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.

How the 88.1/100 breaks down Methodology →
ViolationsHistorical violation record including health-based and monitoring violations.
43.1 / 45A
Lead & CopperLead at 4.9 ppb (90th percentile).
18 / 20A
ContaminantsNo PFAS compounds detected.
20 / 20A
ComplianceMonitoring and reporting compliance with EPA regulations.
3 / 10F
Source RiskWater source: Purchased surface water.
4 / 5B

02What's in Larchmont (V)'s water

Every contaminant flagged in Larchmont (V), 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.

1 detection · sorted by % of legal limit
Over the limit Elevated — watch Within limits
0 50% LEGAL LIMIT 150%
31 contaminants tested under EPA SDWIS, LCR and UCMR programs · 1 detected

Full contaminants report

Contaminant Detected Level EPA Limit Unit Category Status
Lead (90th percentile) 4.9 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 ND HI µg/L PFAS Not 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 ND HI µg/L PFAS Not 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 ND HI µg/L PFAS Not 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.

03Larchmont (V)'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 5 violations on record, including 0 health-based violations. 3 remain unresolved.

9 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 monitoring & paperwork
UpdateWater quality data updatedLatest EPA compliance and testing data incorporated into Larchmont (V)'s water quality assessment. Grade: A- (88.1/100).
DisasterSEVERE STORM AND FLOODINGFederal disaster declaration (FEMA DR-4755). Flood event — may have impacted local water infrastructure.
DisasterREMNANTS OF HURRICANE IDAFederal disaster declaration (FEMA DR-4615). Hurricane event — may have impacted local water infrastructure.
Violation2 drinking water violations recordedContaminants: TTHM, Total Haloacetic Acids (HAA5).Resolved
Violation1 drinking water violation recordedContaminants: Consumer Confidence Rule.Open
Violation1 drinking water violation recordedContaminants: Consumer Confidence Rule.Open
Lead, 90th percentileppb · lower is better
0204060EPA action level · 15 ppb1992 — 51 ppb2000 — 11 ppb2001 — 12 ppb2002 — 7 ppb2003 — 14 ppb2004 — 5 ppb2005 — 5.6 ppb2006 — 9.8 ppb2009 — 13 ppb2011 — 12 ppb2012 — 14 ppb2014 — 15 ppb2017 — 5.7 ppb2020 — 7.7 ppb2023 — 6 ppb2026 — 4.9 ppb514.919922003200920172026

Down 46 ppb since 1992. Latest reading: 4.9 ppb (2026) — 33% of the action level. Sampled at higher-risk homes (90th percentile).

04Where Larchmont (V)'s water comes from

Larchmont (V)'s drinking water comes primarily from surface water sources such as rivers, lakes, or reservoirs.

Source

Purchased Surface Water

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

Treatment

Wholesale supplier

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

Distribution

1 system

1 water system, operated under local government ownership.

Delivery

6,485 people

Residents served across Larchmont (V)'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 6,485 people through 1 water system.

System namePWSIDPopulationSource
LARCHMONT VILLAGE NY5903433 6,485 Purchased Surface Water

Water bodies near Larchmont (V)

Byram River · river Bronx River · river

As a surface-water system, these water bodies may directly influence Larchmont (V)'s drinking water supply.

05Pressure on Larchmont (V)'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.

Flood & storm history

Recurring — declared disasters

10 federal disaster declarations on record for Westchester County. Flooding and severe storms can overwhelm treatment plants, cause sewage overflows, and push runoff into supplies.

SEVERE STORM AND FLOODING Jan 2024 · DR-4755
REMNANTS OF HURRICANE IDA Sep 2021 · DR-4615
REMNANTS OF HURRICANE IDA Sep 2021 · DR-3572

Drought

D2 — severe drought

Westchester County is in D2 (severe drought) per the U.S. Drought Monitor (week of Jul 2026). Drought can raise disinfection-byproduct levels and taste/odor issues as utilities draw from lower reservoirs.

Current streak at D2+ severity4 wks
Weeks at D2+ in the last 5 years4 wks
Months in D2+ over the last 30 years11.6%

06How Larchmont (V) compares

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

New York (C)
89 · A-
Larchmont (V) (this city)
88.1 · A-
Smithtown (T)
84.8 · B+
Islip (T)
71.8 · B-

dashed line = New York average (78/100)

Larchmont (V) scores 88.1/100above the New York average of 78/100. It outscores 8 of 10 nearby cities. Full New York rankings →

Westchester 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 Larchmont (V)'s water — not generic advice.

Extra protection

A basic carbon filter still helps

Larchmont (V)'s water meets federal standards, but a simple carbon filter improves taste and adds a margin of safety against short-term issues.

Compare tested filters →
Because lead was detected

Flush taps & check your service line

Lead leaches from pipes as water sits. Run cold water 30 seconds before drinking (especially mornings), and ask the utility whether your address still has a lead service line.

Lead risks explained →
Stay informed

Watch for Larchmont (V) alerts

This area has a history of flood declarations — after severe weather, watch for boil-water advisories from the utility, and check the live alerts on this page.

All water alerts →

Frequently asked questions

Is Larchmont (V), NY tap water safe to drink?

Larchmont (V)'s water quality earned a grade of A- (88.1/100). The water generally meets EPA standards and is considered safe for consumption. The city ranks #322 out of 810 cities tested in New York.

What contaminants are in Larchmont (V)'s water?

Lead was measured at 4.9 ppb (90th percentile). No PFAS compounds were detected. 5 violations are on record.

How is Larchmont (V)'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 Larchmont (V)?

Based on current data, basic filtration should suffice for additional peace of mind.

Where does Larchmont (V)'s water come from?

Larchmont (V)'s water is sourced from Purchased surface water. The city has 1 water system serving approximately 6,485 residents.

How does Larchmont (V)'s water compare to other cities?

Larchmont (V) ranks #322 out of 810 cities in New York (better than 60% of state cities) and #3607 out of 15382 cities nationally (77th percentile). The grade of A- reflects the combined assessment of violation history, lead and copper levels, PFAS contamination, and regulatory compliance.

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About Larchmont (V), NY: Larchmont is a village located within the Town of Mamaroneck in Westchester County, New York. Larchmont is a suburb of New York City, located approximately 18 miles (29 km) northeast of Midtown Manhattan. As of the 2020 census, Larchmont had a population of 6,630. In February 2019, Bloomberg ranked Larchmont as the 15th wealthiest place in the United States and the third wealthiest in New York. Median household income $220,714 · median home value $1,353,103 · median age 37.7 · 73.3% homeowners · 80% college educated. Wikipedia → 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.