WaterVerge

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

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

20K residents served 1 water system PWSID: NY2902822
Overall Score
85.8 / 100
Violations
None active
Last Updated
May 2026
Source
Groundwater
#428 of 855 in New York Top 32% nationally
Public/Private
High data confidence
Reviewed by WaterVerge Editorial Team · Last updated May 2026
A-GRADE
Water Quality Grade
85.8/100
waterverge.com
A- 85.8/100

Hempstead (T), NY — Water Quality Report

Hempstead (T)'s drinking water received a grade of A- (85.8 out of 100), indicating good water quality. The city's 1 water system serves approximately 20,000 residents using groundwater.

Lead levels were measured at 0.0 ppb (90th percentile), well within EPA limits. PFAS testing under UCMR 5 found no detectable forever chemicals.

The system has 33 violations on record, including 5 health-based violations. All violations have been resolved.

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

What to know about Hempstead (T)'s water

Hempstead (T) ranks #428 out of 855 cities in New York for water quality, placing it mid-range 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.

Hexavalent chromium (chromium-6) was detected at 0.39 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 28 violations in the past five years, suggesting a pattern of compliance challenges that residents should monitor closely.

Quality Breakdown

Water quality score

See methodology →
85.8 out of 100 Grade A-
A: 90-100
B: 74-89
C: 60-73
F: <50
How is this calculated?
Violations
33.1/45
C
Historical violation record including health-based and monitoring violations.
Lead & Copper
20/20
A
Lead at 0.0 ppb (90th percentile).
Contaminants
17.7/20
B
No 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?

Generally Safe

Based on EPA testing data, Hempstead (T)'s tap water is generally safe to drink. The water system earned a grade of A- (85.8/100), meeting federal drinking water standards across key contaminant categories. The city's 1 water system serves approximately 20,000 residents using groundwater (wells).

28
Violations (5yr)
0.0 ppb
Lead (90th %ile)
None
PFAS Detected
10 events
Disaster History

Recent water quality updates for Hempstead (T)

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

Update
Water quality data updated

Latest EPA compliance and testing data incorporated into Hempstead (T)'s water quality assessment. Grade: A- (85.8/100).

Disaster
SEVERE STORM AND FLOODING

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

Violation
28 drinking water violations recorded

Contaminants: BHC-GAMMA, Methoxychlor, Toxaphene.

Disaster
REMNANTS OF HURRICANE IDA

Federal disaster declaration (FEMA DR-4615). Hurricane event — may have impacted local water infrastructure.

Violation
1 drinking water violation recorded

1 health-based. Contaminants: Coliform (TCR).

Violation
1 drinking water violation recorded

1 health-based. Contaminants: Coliform (TCR).

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.

Violation history

Hempstead (T)'s water system has 33 total violations on record, including 5 health-based violations. All violations have been resolved. 28 violations were issued in the last 5 years.

MRMCL
Most recent violations:
Jan 2022 BHC-GAMMA Resolved
Jan 2022 Methoxychlor Resolved
Jan 2022 Toxaphene Resolved
Jan 2022 Dalapon Resolved
Jan 2022 Picloram 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 1 water system serving approximately 20,000 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

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
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
0.39 µg/L
CA MCL (no federal MCL): 10 µg/L · 4% of limit
DetectedUCMR 3 Data
Strontium
Inorganic
Detected
58.0 µg/L
EPA Health Ref Level: 1,500 µg/L · 4% of limit
DetectedUCMR 3 Data
1,4-Dioxane
Organic
Over HA
1.50 µg/L
EPA Health Advisory: 0.35 µg/L · +20% over limit
Over Health AdvisoryUCMR 3 Data
Manganese
Inorganic
Over SMCL
69.4 µg/L
EPA Secondary MCL: 50 µg/L · +20% over limit
Over SMCLUCMR 4 Data
Vanadium
Inorganic
Detected
0.20 µg/L
EPA Short-term HA: 21 µg/L · 1% of limit
DetectedUCMR 3 Data
Chlorate
Disinfection Byproduct
Over HA
870.0 µg/L
EPA Lifetime HA: 210 µg/L · +20% over limit
Over Health AdvisoryUCMR 3 Data
Cobalt
Inorganic
Detected
84.00 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
0
Detected
0
Exceed EPA MCL
Compliance Record

Violation summary

33
Total violations
5
Health-based
0
Active / unresolved
Jan 2022
Most recent violation
Compliance Record

Violations & advisories

33 Total
0 Active
5 Health-based
33 Resolved
Violations by category
Synthetic Organic Chemicals
28
Total Coliform Rule
5
Jan 2022 Resolved
BHC-GAMMA
Monitoring & Reporting
Monitoring & Reporting Resolved Jun 2023
Jan 2022 Resolved
Methoxychlor
Monitoring & Reporting
Monitoring & Reporting Resolved Jun 2023
Jan 2022 Resolved
Toxaphene
Monitoring & Reporting
Monitoring & Reporting Resolved Jun 2023
Jan 2022 Resolved
Dalapon
Monitoring & Reporting
Monitoring & Reporting Resolved Jun 2023
Jan 2022 Resolved
Picloram
Monitoring & Reporting
Monitoring & Reporting Resolved Jun 2023
Jan 2022 Resolved
Dinoseb
Monitoring & Reporting
Monitoring & Reporting Resolved Jun 2023
Jan 2022 Resolved
Hexachlorocyclopentadiene
Monitoring & Reporting
Monitoring & Reporting Resolved Jun 2023
Jan 2022 Resolved
Aldicarb sulfone
Monitoring & Reporting
Monitoring & Reporting Resolved Jun 2023
Jan 2022 Resolved
Carbofuran
Monitoring & Reporting
Monitoring & Reporting Resolved Jun 2023
Jan 2022 Resolved
Aldicarb
Monitoring & Reporting
Monitoring & Reporting Resolved Jun 2023
Jan 2022 Resolved
LASSO
Monitoring & Reporting
Monitoring & Reporting Resolved Jun 2023
Jan 2022 Resolved
Heptachlor
Monitoring & Reporting
Monitoring & Reporting Resolved Jun 2023
Jan 2022 Resolved
2,4-D
Monitoring & Reporting
Monitoring & Reporting Resolved Jun 2023
Jan 2022 Resolved
Pentachlorophenol
Monitoring & Reporting
Monitoring & Reporting Resolved Jun 2023
Jan 2022 Resolved
Total Polychlorinated Biphenyls (PCB)
Monitoring & Reporting
Monitoring & Reporting Resolved Jun 2023
Jan 2022 Resolved
Chlordane
Monitoring & Reporting
Monitoring & Reporting Resolved Jun 2023
Jan 2022 Resolved
Endrin
Monitoring & Reporting
Monitoring & Reporting Resolved Jun 2023
Jan 2022 Resolved
Di(2-ethylhexyl) phthalate
Monitoring & Reporting
Monitoring & Reporting Resolved Jun 2023
Jan 2022 Resolved
Simazine
Monitoring & Reporting
Monitoring & Reporting Resolved Jun 2023
Jan 2022 Resolved
ETHYLENE DIBROMIDE
Monitoring & Reporting
Monitoring & Reporting Resolved Jun 2023
Showing 20 of 33 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

Full contaminants report

Contaminant Detected Level EPA Limit Unit Category Status
Lead (90th percentile) 0.0 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 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.

Lead level trend (90th percentile)

EPA action level: 15 ppb
Lead has decreased by 5.0 ppb from 1992 (5.0 ppb) to 2023 (0.0 ppb).
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
20,000
Water Systems
1
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 20,000 people through 1 water system.

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
FRANKLIN SQUARE WD NY2902822 20,000 GW
Regional Comparison

How Hempstead (T) compares

Full New York rankings →

Hempstead (T)'s score of 85.8/100 is above the average of 74/100 among major New York cities. It outscores 9 of 10 nearby cities.

Hempstead (T) (this city)
85.8
New York avg
74
City Profile

About Hempstead (T), NY

Wikipedia →

Franklin Square is a hamlet and census-designated place (CDP) within the Town of Hempstead in Nassau County, on Long Island, in New York, United States. The population was 30,903 at the time of the 2020 census.

Economic Profile
$136,225
Median Income
$619,770
Median Home Value
$2,068/mo
Median Rent
3.9%
Unemployment
Community
40.7
Median Age
4,286
People / sq mi
38%
College Educated
83.6%
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 A- (85.8/100). The water generally meets EPA standards and is considered safe for consumption. The city ranks #428 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). No PFAS compounds were detected. 33 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)?

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

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

Hempstead (T)'s water is sourced from Groundwater. The city has 1 water system serving approximately 20,000 residents.

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

Hempstead (T) has 5 health-based violations on record. The most recent violation was recorded in January 2022. Health-based violations mean the water exceeded EPA maximum contaminant levels (MCLs) for a regulated substance. All health violations have been resolved.

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 33 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.

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

Hempstead (T) ranks #428 out of 855 cities in New York (better than 50% of state cities) and #5073 out of 15744 cities nationally (68th percentile). The grade of A- reflects the combined assessment of violation history, lead and copper levels, PFAS contamination, and regulatory compliance.