Is Smithtown (T), NY Tap Water Safe to Drink?
Graded C — but 1,4-Dioxane, Manganese and 3 more were detected above EPA limits. Here's what's in the water and how to remove it. What to do next ↓
60.9/100
waterverge.com Smithtown (T), NY — Water Quality Report
Smithtown (T)'s drinking water received a grade of C (60.9 out of 100), indicating fair water quality. The city's 4 water systems serve approximately 1,105,797 residents using groundwater.
Lead levels were measured at 1.3 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 95 violations on record, including 3 health-based violations. 10 remain unresolved.
What to know about Smithtown (T)'s water
Smithtown (T) ranks #751 out of 855 cities in New York for water quality, placing it among the lowest-rated in the state.
Smithtown (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 5.59 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.
As a major metropolitan system serving over 1.1M residents, Smithtown (T) faces large-scale infrastructure challenges including aging pipes and the complexity of treating water across a vast distribution network.
The system has seen 31 violations in the past five years, suggesting a pattern of compliance challenges that residents should monitor closely.
Water quality score
See methodology →Is Smithtown (T), NY water safe to drink?
Smithtown (T)'s drinking water has significant quality concerns based on EPA testing data. With a grade of C (60.9/100), the system has issues across multiple categories. A water filter is recommended for all residents. The city's 4 water systems serve approximately 1,105,797 residents using groundwater (wells).
Recent water quality updates for Smithtown (T)
A timeline of significant water quality events, violations, and data updates.
PFAS levels exceed EPA maximum contaminant levels. Reverse osmosis or activated carbon filtration recommended.
Latest EPA compliance and testing data incorporated into Smithtown (T)'s water quality assessment. Grade: C (60.9/100).
Contaminants: Endrin, BHC-GAMMA, Methoxychlor.
Contaminants: Radium-226, Radium-228.
Federal disaster declaration (FEMA DR-4615). Hurricane event — may have impacted local water infrastructure.
Federal disaster declaration (FEMA DR-3572). Hurricane event — may have impacted local water infrastructure.
Key contaminant findings
Based on the most recent EPA sampling data for Smithtown (T)'s water supply.
Well within EPA limits.
PFAS "forever chemicals" exceed EPA maximum contaminant levels. Reverse osmosis or granular activated carbon filtration strongly recommended.
The "Erin Brockovich" chemical. There is no federal MCL, but California has set a limit of 10 µg/L. Reverse osmosis filtration is effective at removing hexavalent chromium.
PFAS "forever chemicals" detected
UCMR 5 testing found 10 PFAS compounds in Smithtown (T)'s water supply. PFAS are synthetic chemicals that persist indefinitely in the environment and the human body.
Violation history
Smithtown (T)'s water system has 95 total violations on record, including 3 health-based violations. 10 remain unresolved. 31 violations were issued in the last 5 years.
Flood & environmental risk
Suffolk County has experienced 10 federally declared disasters since 1999. 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 Connetquot Bk Nr Central Islip, Carlls River.
Where does Smithtown (T)'s water come from?
Smithtown (T)'s drinking water comes from groundwater (wells), supplied by 4 water systems serving approximately 1,105,797 people. Groundwater is generally less susceptible to surface contamination but can contain naturally occurring contaminants like arsenic, radon, and nitrate. Nearby water bodies include Connetquot Bk Nr Central Islip (river), Carlls River (river).
What Smithtown (T) residents can do
Recommended: Reverse osmosis system. This addresses the specific contaminants found in Smithtown (T)'s water.
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.
Smithtown (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.
Top contaminants to know
View all ↓Forever chemicals overview
National PFAS report →Violation summary
Violations & advisories
Drought conditions
D1 — moderate droughtSuffolk 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.
Source: U.S. Drought Monitor, updated weekly by NDMC, USDA, and NOAA.
Flood & disaster history
Suffolk County has experienced 10 federally declared disasters since 1999. Flooding and severe weather can compromise water treatment infrastructure and introduce contaminants into drinking water supplies.
Recommended water filters
Based on contaminants detected in Smithtown (T)'s water supply, we recommend the following filter types.
Full contaminants report
| Contaminant | Detected Level | EPA Limit | Unit | Category | Status |
|---|---|---|---|---|---|
| Lead (90th percentile) LeadHeavy Metal A toxic heavy metal that can leach into drinking water from older pipes, solder, and fixtures. No amount of lead in water is considered safe. Health EffectsBrain and nervous system damage in children, kidney damage, high blood pressure, and reproductive problems in adults. EPA Limit15 ppb action level Common SourcesCorrosion of lead pipes, lead solder, brass faucets, and household plumbing. | 1.3 | 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 6:2 FTSPFAS A fluorotelomer sulfonate commonly found at sites contaminated with aqueous film-forming foam (AFFF) used in firefighting. Health EffectsPotential liver toxicity and endocrine disruption. Less studied but identified as a contaminant of concern. EPA LimitNo individual MCL (not yet regulated) Common SourcesFirefighting foam (AFFF), airports, military bases, and industrial facilities. | 0.024 | 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 HFPO-DA (GenX)PFAS A replacement for PFOA in manufacturing, marketed as safer but still a persistent "forever chemical." Also known as GenX. Health EffectsLiver and kidney effects, reproductive toxicity, immune system effects, and potential cancer risk. EPA Limit10 ppt MCL Common SourcesFluoropolymer manufacturing (used as PFOA replacement), industrial wastewater discharge. | ND | 0.01 | µg/L | PFAS | Not Detected |
| lithium LithiumInorganic A naturally occurring alkali metal found in groundwater. Monitored under UCMR 5 to assess occurrence in drinking water. Health EffectsKidney effects at high doses. Low-level exposure effects under study; some research suggests neurological effects. EPA LimitNo MCL (monitoring only under UCMR 5) Common SourcesNatural mineral deposits, geothermal water, and industrial discharge. | 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 PFBAPFAS One of the shortest-chain PFAS compounds. Very mobile in water and difficult to remove with standard filtration. Health EffectsThyroid effects, potential developmental toxicity. Shorter half-life in body than long-chain PFAS. EPA LimitNo individual MCL (not yet regulated) Common SourcesDegradation of longer-chain PFAS, industrial discharge, and firefighting foam. | 0.122 | HI | µg/L | PFAS | Detected |
| PFBS PFBSPFAS A short-chain PFAS used as a replacement for PFOS. While it clears the body faster than long-chain PFAS, it still persists in the environment. Health EffectsThyroid effects, reproductive and developmental toxicity, kidney effects. EPA LimitPart of Hazard Index (1.0) Common SourcesIndustrial discharge, firefighting foam, and as a replacement chemical in manufacturing. | 0.005 | 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 PFHpAPFAS A medium-chain PFAS compound found in various environmental samples. Less studied than PFOA/PFOS but still considered a contaminant of concern. Health EffectsLiver effects, potential developmental toxicity, and endocrine disruption. EPA LimitPart of Hazard Index (1.0) Common SourcesDegradation of longer-chain PFAS, industrial discharge, and contaminated water sources. | 0.010 | HI | µg/L | PFAS | Detected |
| PFHpS | ND | HI | µg/L | PFAS | Not Detected |
| PFHxA PFHxAPFAS A short-chain PFAS replacement chemical widely used after manufacturers phased out longer-chain PFAS. Very commonly detected in water. Health EffectsLiver and kidney effects, potential thyroid disruption. Considered less toxic than long-chain PFAS but still persistent. EPA LimitNo individual MCL (not yet regulated) Common SourcesIndustrial processes, firefighting foam (AFFF), food packaging, and textile treatment. | 0.043 | HI | µg/L | PFAS | Detected |
| PFHxS PFHxSPFAS A medium-chain PFAS found in firefighting foam and consumer products. It has a long half-life in the human body, similar to long-chain PFAS. Health EffectsImmune system effects, thyroid disruption, and potential reproductive and developmental harm. EPA LimitPart of Hazard Index (1.0) Common SourcesFirefighting foam (AFFF), waterproof textiles, food packaging, and industrial discharge. | 0.011 | HI | µg/L | PFAS | Detected |
| PFMBA | ND | HI | µg/L | PFAS | Not Detected |
| PFMPA | ND | HI | µg/L | PFAS | Not Detected |
| PFNA PFNAPFAS A long-chain PFAS compound used in manufacturing fluoropolymers. It bioaccumulates in the body and is very persistent in the environment. Health EffectsDevelopmental effects, liver toxicity, immune suppression, and potential cancer risk. EPA LimitPart of Hazard Index (1.0) Common SourcesFluoropolymer manufacturing, industrial emissions, and contaminated water sources. | 0.006 | HI | µg/L | PFAS | Detected |
| PFOA PFOAPFAS A long-chain PFAS ("forever chemical") once widely used in nonstick coatings and firefighting foam. It persists in the body and environment for years. Health EffectsLinked to kidney and testicular cancer, thyroid disease, elevated cholesterol, and reproductive issues. EPA Limit4.0 ppt MCL Common SourcesIndustrial discharge, firefighting foam (AFFF), nonstick cookware manufacturing, and contaminated groundwater. | 0.006 | 0.004 | µg/L | PFAS | Over MCL |
| PFOS PFOSPFAS A long-chain PFAS compound historically used in stain-resistant coatings and firefighting foam. One of the most studied and persistent PFAS chemicals. Health EffectsLiver damage, immune system suppression, thyroid disruption, increased cholesterol, and potential cancer risk. EPA Limit4.0 ppt MCL Common SourcesFirefighting foam (AFFF), industrial sites, stain-resistant fabric treatments, and contaminated groundwater. | 0.017 | 0.004 | µg/L | PFAS | Over MCL |
| PFPeA PFPeAPFAS A short-chain PFAS compound commonly detected in drinking water. One of the most frequently found PFAS in UCMR 5 monitoring. Health EffectsLess studied than PFOA/PFOS. Potential liver and thyroid effects. Research is ongoing. EPA LimitNo individual MCL (not yet regulated) Common SourcesIndustrial discharge, firefighting foam degradation, and consumer products. | 0.039 | 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 |
Lead level trend (90th percentile)
See how Smithtown (T) compares by contaminant
Explore where Smithtown (T) ranks among all New York cities for specific contaminants.
Water source & infrastructure
Where Smithtown (T)'s water comes from
Smithtown (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 local government ownership and serves approximately 1,105,797 people through 4 water systems.
Water bodies near Smithtown (T)
Smithtown (T) is located near 2 notable water bodies. These water bodies contribute to the regional watershed and may indirectly affect groundwater quality.
Water systems serving Smithtown (T)
| System Name | PWSID | Population | Source |
|---|---|---|---|
| SUFFOLK COUNTY WATER AUTHORITY | NY5110526 | 1,100,000 | GW |
| BROOKHAVEN NATIONAL LABORATORY | NY5111891 | 3,500 | GW |
| SEAVIEW WATER COMPANY | NY5110600 | 1,400 | GW |
| CALVERTON HILLS OWNERS ASSOCIATION | NY5112134 | 897 | GW |
How Smithtown (T) compares
Full New York rankings →Smithtown (T)'s score of 60.9/100 is below the average of 76/100 among major New York cities. It outscores 1 of 10 nearby cities. 9 of 10 nearby cities score higher.
Nearby cities
View New York rankings →Compare Smithtown (T) water quality
Head-to-head reports vs other large US cities — grades, lead, PFAS, and Superfund / TRI proximity.
- Smithtown (T) vs New York (C), NY
- Smithtown (T) vs Smithtown (T), NY
- Smithtown (T) vs Smithtown (T), NY
- Smithtown (T) vs Smithtown (T), NY
- Smithtown (T) vs Smithtown (T), NY
About Smithtown (T), NY
Wikipedia →Hauppauge is a hamlet and census-designated place (CDP) in the towns of Islip and Smithtown in western Suffolk County, New York, on Long Island. The population was 20,803 at the time of the 2020 census.
Learn more about your water
Guides and resources related to Smithtown (T)'s water quality findings.
Explore water quality across Suffolk
Frequently asked questions
Is Smithtown (T), NY tap water safe to drink?
Smithtown (T)'s water quality earned a grade of C (60.9/100). Some concerns have been identified. Consider a water filter for an extra layer of protection. The city ranks #751 out of 855 cities tested in New York.
What contaminants are in Smithtown (T)'s water?
Lead was measured at 1.3 ppb (90th percentile). 10 PFAS compounds were detected. 95 violations are on record.
How is Smithtown (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 Smithtown (T)?
PFAS compounds exceed EPA limits — a reverse osmosis or activated carbon filter is recommended.
Where does Smithtown (T)'s water come from?
Smithtown (T)'s water is sourced from Groundwater. The city has 4 water systems serving approximately 1,105,797 residents.
What health violations has Smithtown (T)'s water system had?
Smithtown (T) has 3 health-based violations on record. The most recent violation was recorded in January 2023. Health-based violations mean the water exceeded EPA maximum contaminant levels (MCLs) for a regulated substance. 10 violations remain unresolved.
Is Smithtown (T)'s groundwater at risk of contamination?
Smithtown (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 95 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 Smithtown (T) have so many PFAS compounds in its water?
10 different PFAS "forever chemical" compounds were detected in Smithtown (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 Smithtown (T)'s water compare to other cities?
Smithtown (T) ranks #751 out of 855 cities in New York (better than 12% of state cities) and #12031 out of 15744 cities nationally (24th percentile). The grade of C reflects the combined assessment of violation history, lead and copper levels, PFAS contamination, and regulatory compliance.