WaterVerge

Is Hempstead (T), NY Tap Water Safe to Drink?

Graded F — but Copper, 1,4-Dioxane and 3 more were detected above EPA limits. Here's what's in the water and how to remove it. What to do next ↓

274K residents served 8 water systems PWSID: NY2902830
Overall Score
39.8 / 100
Violations
3 active
Last Updated
May 2026
Source
Groundwater
#849 of 855 in New York Top 97% nationally
Public/Private
High data confidence
Reviewed by WaterVerge Editorial Team · Last updated May 2026
FGRADE
Water Quality Grade
39.8/100
waterverge.com
F 39.8/100

Hempstead (T), NY — Water Quality Report

Hempstead (T)'s drinking water received a grade of F (39.8 out of 100), indicating failing water quality. The city's 8 water systems serve approximately 274,305 residents using groundwater.

Lead levels were measured at 0.0 ppb (90th percentile), well within EPA limits. UCMR 5 testing detected 10 PFAS compounds, with levels exceeding EPA maximum contaminant levels in the water supply.

The system has 918 violations on record, including 9 health-based violations. 3 remain unresolved.

Data last updated: May 2026 · Source: EPA SDWIS, UCMR 5
Analysis

What to know about Hempstead (T)'s water

Hempstead (T) ranks #849 out of 855 cities in New York for water quality, placing it among the lowest-rated in the state.

Hempstead (T) relies on groundwater, which is generally less vulnerable to surface contamination but can be affected by naturally occurring minerals like arsenic and nitrate, as well as agricultural and industrial runoff.

Of particular concern: PFAS "forever chemical" levels exceed the 2024 EPA maximum contaminant levels. These synthetic compounds don't break down naturally and require specialized filtration such as reverse osmosis or granular activated carbon.

Hexavalent chromium (chromium-6) was detected at 3.90 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.

The system has seen 225 violations in the past five years, suggesting a pattern of compliance challenges that residents should monitor closely.

Quality Breakdown

Water quality score

See methodology →
39.8 out of 100 Grade F
A: 90-100
B: 74-89
C: 60-73
F: <50
How is this calculated?
Violations
0/45
F
Historical violation record including health-based and monitoring violations.
Lead & Copper
16/20
B
Lead at 0.0 ppb (90th percentile).
Contaminants
8.7/20
F
10 PFAS compounds detected.
Compliance
10/10
A
Monitoring and reporting compliance with EPA regulations.
Source Risk
5/5
A
Water source: Groundwater.
Water Safety

Is Hempstead (T), NY water safe to drink?

Concerns Identified

Hempstead (T)'s drinking water has significant quality concerns based on EPA testing data. With a grade of F (39.8/100), the system has issues across multiple categories. A water filter is recommended for all residents. The city's 8 water systems serve approximately 274,305 residents using groundwater (wells).

3
Active Violations
0.0 ppb
Lead (90th %ile)
10 compounds
PFAS Detected
10 events
Disaster History

Recent water quality updates for Hempstead (T)

A timeline of significant water quality events, violations, and data updates.

PFAS
10 PFAS "forever chemical" compounds detected

PFAS levels exceed EPA maximum contaminant levels. Reverse osmosis or activated carbon filtration recommended.

Update
Water quality data updated

Latest EPA compliance and testing data incorporated into Hempstead (T)'s water quality assessment. Grade: F (39.8/100).

Violation
56 drinking water violations recorded

Contaminants: Endrin, Di(2-ethylhexyl) phthalate, Dinoseb.

Violation
56 drinking water violations recorded

Contaminants: Aldicarb sulfone, HEXACHLOROBENZENE, Benzo(a)pyrene.

Violation
56 drinking water violations recorded

Contaminants: Endrin, BHC-GAMMA, Toxaphene.

Disaster
SEVERE STORM AND FLOODING

Federal disaster declaration (FEMA DR-4755). Flood event — may have impacted local water infrastructure.

Key contaminant findings

Based on the most recent EPA sampling data for Hempstead (T)'s water supply.

Lead Within Limits
Detected: 0.0 ppb Limit: 15 ppb (EPA Action Level)

Well within EPA limits.

Copper Exceeds Limit
Detected: 1.50 mg/L Limit: 1.3 mg/L (EPA Action Level)

Exceeds EPA action level. Copper can leach from household plumbing — flush taps for 30 seconds before drinking.

PFAS (10 compounds) Elevated
Detected: Highest: PFNA at 0.0190 µg/L Limit: 0.004 µg/L (EPA MCL)

PFAS "forever chemicals" exceed EPA maximum contaminant levels. Reverse osmosis or granular activated carbon filtration strongly recommended.

PFAS "forever chemicals" detected

UCMR 5 testing found 10 PFAS compounds in Hempstead (T)'s water supply. PFAS are synthetic chemicals that persist indefinitely in the environment and the human body.

Compound Level EPA MCL Status
PFNA 0.0190 µg/L 0.004 µg/L Within Limit
PFOA 0.0120 µg/L 0.004 µg/L Over MCL
PFPeA 0.0095 µg/L 0.004 µg/L Within Limit
PFHxA 0.0074 µg/L 0.004 µg/L Within Limit

Violation history

Hempstead (T)'s water system has 918 total violations on record, including 9 health-based violations. 3 remain unresolved. 225 violations were issued in the last 5 years.

MRMONMCL
Most recent violations:
Jan 2025 Endrin Resolved
Jan 2025 Di(2-ethylhexyl) phthalate Resolved
Jan 2025 Dinoseb Resolved
Jan 2025 Hexachlorocyclopentadiene Resolved
Jan 2025 Aldicarb sulfoxide Resolved

Flood & environmental risk

Nassau County has experienced 10 federally declared disasters since 2005. Flooding and severe storms can overwhelm water treatment plants, cause sewage overflows, and introduce agricultural runoff, bacteria, and sediment into drinking water supplies. Local water sources include Alley Creek, East Meadow Brook, Hempstead Lake, Valley Stream, Conselyeas Pond Tributary.

SEVERE STORM AND FLOODING
Flood FEMA DR-4755
REMNANTS OF HURRICANE IDA
Hurricane FEMA DR-4615
REMNANTS OF HURRICANE IDA
Hurricane FEMA DR-3572

Where does Hempstead (T)'s water come from?

Hempstead (T)'s drinking water comes from groundwater (wells), supplied by 8 water systems serving approximately 274,305 people. Groundwater is generally less susceptible to surface contamination but can contain naturally occurring contaminants like arsenic, radon, and nitrate. Nearby water bodies include Alley Creek (river), East Meadow Brook (river), Hempstead Lake (lake), Valley Stream (river), Conselyeas Pond Tributary (river).

What Hempstead (T) residents can do

Install a water filter

Recommended: Reverse osmosis system. This addresses the specific contaminants found in Hempstead (T)'s water.

Request your utility's CCR

Your water utility is required to publish an annual Consumer Confidence Report (CCR) with detailed testing results. Ask for the latest copy or check your utility's website.

Monitor alerts during storms

Hempstead (T)'s area has a history of flooding. After severe weather, watch for boil water advisories from your local utility.

Data: EPA SDWIS, UCMR 5 (PFAS), FEMA, NOAA. Last updated May 2026.

Contaminant Alerts

Top contaminants to know

View all ↓
Lead (90th percentile)
Inorganic / Heavy Metal
Safe
0.0 ppb
EPA Action Level: 15 ppb · 0% of limit
Safe Level
Copper (90th percentile)
Inorganic
Over Limit
1.50 mg/L
EPA Action Level: 1.3 mg/L · +15% over limit
Exceeds Limit
PFNA
PFAS / Forever Chemical
Near MCL
0.0190 µg/L
EPA MCL: 0.004 µg/L · +20% over limit
Detected
HAA5 (Disinfection Byproducts)
Disinfection Byproduct
Safe
1.0 µg/L
EPA MCL: 60 µg/L · 2% of limit
Within LimitUCMR 4 DataHAA6Br: 1.3 µg/LHAA9: 1.5 µg/L
Chromium-6 (Hexavalent Chromium)
Inorganic
Detected
3.90 µg/L
CA MCL (no federal MCL): 10 µg/L · 39% of limit
DetectedUCMR 3 Data
Strontium
Inorganic
Detected
306.0 µg/L
EPA Health Ref Level: 1,500 µg/L · 20% of limit
DetectedUCMR 3 Data
1,4-Dioxane
Organic
Over HA
10.00 µg/L
EPA Health Advisory: 0.35 µg/L · +20% over limit
Over Health AdvisoryUCMR 3 Data
Manganese
Inorganic
Over SMCL
213.0 µg/L
EPA Secondary MCL: 50 µg/L · +20% over limit
Over SMCLUCMR 4 Data
Perchlorate
Inorganic
Over CA MCL
14.00 µg/L
CA MCL (no federal MCL): 6 µg/L · +20% over limit
Over CA MCLUCMR 1 Data (2001–2005)
Vanadium
Inorganic
Detected
0.87 µg/L
EPA Short-term HA: 21 µg/L · 4% of limit
DetectedUCMR 3 Data
Chlorate
Disinfection Byproduct
Over HA
680.0 µg/L
EPA Lifetime HA: 210 µg/L · +20% over limit
Over Health AdvisoryUCMR 3 Data
Cobalt
Inorganic
Detected
2.60 µg/L
No federal limit: N/A µg/L · 50% of limit
DetectedNo federal MCLUCMR 3 Data
PFAS Testing

Forever chemicals overview

National PFAS report →
30
Compounds tested
10
Detected
2
Exceed EPA MCL
4.72
Hazard Index
PFOS max: 0.0069 µg/L PFOA max: 0.0120 µg/L
Compliance Record

Violation summary

918
Total violations
9
Health-based
3
Active / unresolved
Jan 2025
Most recent violation
Compliance Record

Violations & advisories

918 Total
3 Active
9 Health-based
915 Resolved
Violations by category
Synthetic Organic Chemicals
729
Volatile Organic Chemicals
160
Nitrate Rule
11
Total Coliform Rule
11
Stage 2 Disinfectants and Disinfection Byproducts Rule
2
Active
Compliance Violation
Monitoring 0
Active
Compliance Violation
Monitoring 0
Active
Compliance Violation
Monitoring 0
Jan 2025 Resolved
Endrin
Monitoring & Reporting
Monitoring & Reporting Resolved Mar 2025
Jan 2025 Resolved
Di(2-ethylhexyl) phthalate
Monitoring & Reporting
Monitoring & Reporting Resolved Mar 2025
Jan 2025 Resolved
Dinoseb
Monitoring & Reporting
Monitoring & Reporting Resolved Mar 2025
Jan 2025 Resolved
Hexachlorocyclopentadiene
Monitoring & Reporting
Monitoring & Reporting Resolved Mar 2025
Jan 2025 Resolved
Aldicarb sulfoxide
Monitoring & Reporting
Monitoring & Reporting Resolved Mar 2025
Jan 2025 Resolved
Aldicarb sulfone
Monitoring & Reporting
Monitoring & Reporting Resolved Mar 2025
Jan 2025 Resolved
OXAMYL
Monitoring & Reporting
Monitoring & Reporting Resolved Mar 2025
Jan 2025 Resolved
LASSO
Monitoring & Reporting
Monitoring & Reporting Resolved Mar 2025
Jan 2025 Resolved
2,4,5-TP
Monitoring & Reporting
Monitoring & Reporting Resolved Mar 2025
Jan 2025 Resolved
HEXACHLOROBENZENE
Monitoring & Reporting
Monitoring & Reporting Resolved Mar 2025
Jan 2025 Resolved
Pentachlorophenol
Monitoring & Reporting
Monitoring & Reporting Resolved Mar 2025
Jan 2025 Resolved
Total Polychlorinated Biphenyls (PCB)
Monitoring & Reporting
Monitoring & Reporting Resolved Mar 2025
Jan 2025 Resolved
Carbofuran
Monitoring & Reporting
Monitoring & Reporting Resolved Mar 2025
Jan 2025 Resolved
Atrazine
Monitoring & Reporting
Monitoring & Reporting Resolved Mar 2025
Jan 2025 Resolved
LASSO
Monitoring & Reporting
Monitoring & Reporting Resolved Mar 2025
Jan 2025 Resolved
2,4-D
Monitoring & Reporting
Monitoring & Reporting Resolved Mar 2025
Jan 2025 Resolved
HEXACHLOROBENZENE
Monitoring & Reporting
Monitoring & Reporting Resolved Mar 2025
Showing 20 of 918 violations
Environmental Risk

Drought conditions

D1 — moderate drought

Nassau County is currently in D1 (moderate drought) per the U.S. Drought Monitor (week of May 5, 2026). Drought can elevate disinfection-byproduct (TTHM/HAA5) levels and taste/odor issues as utilities draw from lower reservoirs.

12.8%
Months in D2+ (last 30y)

Source: U.S. Drought Monitor, updated weekly by NDMC, USDA, and NOAA.

Environmental Risk

Flood & disaster history

10
Declared disasters
Jan 2024
Most recent
Hurricane
Most common type

Nassau County has experienced 10 federally declared disasters since 2005. Flooding and severe weather can compromise water treatment infrastructure and introduce contaminants into drinking water supplies.

Jan 2024
SEVERE STORM AND FLOODING
Flood FEMA #4755
Sep 2021
REMNANTS OF HURRICANE IDA
Hurricane FEMA #4615
Sep 2021
REMNANTS OF HURRICANE IDA
Hurricane FEMA #3572
Aug 2021
HURRICANE HENRI
Hurricane FEMA #3565
Oct 2020
TROPICAL STORM ISAIAS
Hurricane FEMA #4567
Oct 2012
HURRICANE SANDY
Hurricane FEMA #4085

Recommended water filters

Based on contaminants detected in Hempstead (T)'s water supply, we recommend the following filter types.

🧪
For PFAS
Reverse Osmosis or Activated Carbon Block
PFAS compounds exceed EPA maximum contaminant levels
🔧
For Copper
Reverse Osmosis or KDF Filter
Copper exceeds the EPA action level of 1.3 mg/L

Full contaminants report

Contaminant Detected Level EPA Limit Unit Category Status
Lead (90th percentile) 0.0 15 ppb Inorganic Safe
Copper (90th percentile) 1.50 1.3 mg/L Inorganic Over Limit
11Cl-PF3OUdS ND HI µg/L PFAS Not Detected
4:2 FTS ND HI µg/L PFAS Not Detected
6:2 FTS 0.006 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 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 0.007 HI µg/L PFAS Detected
PFBS 0.004 HI µg/L PFAS 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 0.003 HI µg/L PFAS Detected
PFHpS ND HI µg/L PFAS Not Detected
PFHxA 0.007 HI µg/L PFAS Detected
PFHxS 0.004 HI µg/L PFAS Detected
PFMBA ND HI µg/L PFAS Not Detected
PFMPA ND HI µg/L PFAS Not Detected
PFNA 0.019 HI µg/L PFAS Detected
PFOA 0.012 0.004 µg/L PFAS Over MCL
PFOS 0.007 0.004 µg/L PFAS Over MCL
PFPeA 0.009 HI µg/L PFAS 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.

Lead level trend (90th percentile)

EPA action level: 15 ppb
Lead has decreased by 9.0 ppb from 1992 (12.0 ppb) to 2025 (3.0 ppb).

Copper level (90th percentile)

Latest reading: 1.500 mg/L (1992)

EPA action level: 1.3 mg/L

Contaminant Rankings

See how Hempstead (T) compares by contaminant

Explore where Hempstead (T) ranks among all New York cities for specific contaminants.

Infrastructure

Water source & infrastructure

Primary Source
Groundwater
Operator
Public/Private
Population Served
274,305
Water Systems
8
Water Source

Where Hempstead (T)'s water comes from

Groundwater

Hempstead (T)'s drinking water is drawn from underground aquifers through wells.

Groundwater is naturally filtered through rock and soil layers, generally requiring less treatment than surface water. However, it can contain naturally occurring contaminants like arsenic, radon, and minerals.

Agricultural activity, septic systems, and industrial operations near well fields can introduce nitrates, pesticides, and volatile organic compounds.

The system is operated by public/private ownership and serves approximately 274,305 people through 8 water systems.

Local Hydrology

Water bodies near Hempstead (T)

Hempstead (T) is located near 5 notable water bodies. These water bodies contribute to the regional watershed and may indirectly affect groundwater quality.

Alley Creek
river
East Meadow Brook
river
Hempstead Lake
lake
Valley Stream
river
Conselyeas Pond Tributary
river
Infrastructure

Water systems serving Hempstead (T)

System Name PWSID Population Source
WA OF WESTERN NASSAU NY2902830 120,000 GW
MANHASSET LAKEVILLE WD NY2902836 43,000 GW
PORT WASHINGTON WD NY2912267 34,000 GW
WA OF GREAT NECK NORTH NY2902841 31,400 GW
WESTBURY WD NY2902856 20,500 GW
ALBERTSON WD NY2902815 13,500 GW
CARLE PLACE WD NY2902818 9,005 GW
SANDS POINT (V) NY2902852 2,900 GW
Regional Comparison

How Hempstead (T) compares

Full New York rankings →

Hempstead (T)'s score of 39.8/100 is below the average of 74/100 among major New York cities. 10 of 10 nearby cities score higher.

Hempstead (T) (this city)
39.8
New York avg
74
City Profile

About Hempstead (T), NY

Wikipedia →

New Hyde Park is a village within the Towns of Hempstead and North Hempstead in Nassau County, on Long Island, in New York, United States. It is the anchor community of the Greater New Hyde Park area. The population was 10,257 at the time of the 2020 census.

Economic Profile
$144,375
Median Income
$695,880
Median Home Value
$1,658/mo
Median Rent
4.3%
Unemployment
Community
41.7
Median Age
4,661
People / sq mi
48%
College Educated
83.1%
Homeownership
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Frequently asked questions

Is Hempstead (T), NY tap water safe to drink?

Hempstead (T)'s water quality earned a grade of F (39.8/100). Significant issues have been found. A water filter is strongly recommended. The city ranks #849 out of 855 cities tested in New York.

What contaminants are in Hempstead (T)'s water?

Lead was measured at 0.0 ppb (90th percentile). 10 PFAS compounds were detected. 918 violations are on record.

How is Hempstead (T)'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 Hempstead (T)?

PFAS compounds exceed EPA limits — a reverse osmosis or activated carbon filter is recommended.

Where does Hempstead (T)'s water come from?

Hempstead (T)'s water is sourced from Groundwater. The city has 8 water systems serving approximately 274,305 residents.

What health violations has Hempstead (T)'s water system had?

Hempstead (T) has 9 health-based violations on record. The most recent violation was recorded in January 2025. Health-based violations mean the water exceeded EPA maximum contaminant levels (MCLs) for a regulated substance. 3 violations remain unresolved.

Is Hempstead (T)'s groundwater at risk of contamination?

Hempstead (T) uses groundwater, which can be affected by naturally occurring contaminants like arsenic, radon, and nitrate, as well as agricultural runoff and industrial activity. The system has 918 violations on record that may relate to groundwater quality. Groundwater systems are generally less susceptible to surface contamination but should be monitored for emerging contaminants like PFAS.

Why does Hempstead (T) have so many PFAS compounds in its water?

10 different PFAS "forever chemical" compounds were detected in Hempstead (T)'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. Some levels exceed the 2024 EPA maximum contaminant levels — a reverse osmosis or NSF-certified activated carbon filter is strongly recommended.

How does Hempstead (T)'s water compare to other cities?

Hempstead (T) ranks #849 out of 855 cities in New York (better than 1% of state cities) and #15216 out of 15744 cities nationally (3th percentile). The grade of F reflects the combined assessment of violation history, lead and copper levels, PFAS contamination, and regulatory compliance.