Arsenic in Drinking Water in New York
What residents of New York need to know about arsenic in drinking water — including natural geological sources, private well risk, which utilities have documented violations, and how to remove arsenic from tap water.
Source: EPA SDWIS, New York State Department of Health, USGS · Last reviewed: 2025-01-01
Quick Answer
Is arsenic in drinking water a concern in New York?
Yes. New York has documented arsenic in private well water from crystalline bedrock geology across the Hudson Valley, Adirondacks, and Southern Tier. Approximately 20% of New York residents use private wells, and arsenic is one of the most commonly detected contaminants above health guidelines in those wells. The Adirondack region's arsenic-bearing metamorphic and igneous rocks and the Hudson Valley's Piedmont geology create widespread occurrence.
Where does arsenic come from in New York's water?
Crystalline bedrock — granites, gneisses, and metamorphic formations in the Adirondacks, Hudson Valley Piedmont, and Southern Tier — is the primary arsenic source in New York. Private wells drilled into this bedrock are the primary exposure pathway. The Taconic Highlands and Catskill region also have arsenic-bearing formations. Long Island's Coastal Plain sedimentary aquifers have lower arsenic risk, but the Nassau and Suffolk county groundwater faces other quality concerns.
What should New York residents know?
New York State DOH recommends private well testing for arsenic and provides a certified laboratory list. Arsenic testing is required at real estate transfer in many New York jurisdictions. Private well owners throughout the Hudson Valley, Adirondack foothills, Southern Tier, and rural upstate New York should test for arsenic. Standard pitcher filters do not remove arsenic.
Key Facts
| EPA MCL | 10 µg/L (10 ppb) |
| MCLG | Zero |
| Primary source | Crystalline bedrock (Adirondacks, Hudson Valley Piedmont, Southern Tier) — naturally arsenic-bearing |
| Private well concern | ~20% of NY residents on private wells — arsenic is a top priority contaminant |
| State regulator | New York State Department of Health |
| Health effects | Bladder, lung, skin cancer; cardiovascular; diabetes risk |
| Effective treatment | Reverse osmosis or activated alumina — pitcher filters do NOT remove arsenic |
Why Arsenic Matters in New York
New York's arsenic occurrence in private wells is tied to the same crystalline bedrock geology that makes New England wells high-risk. The Hudson Valley and Taconic Mountains share geology with Connecticut and Massachusetts where arsenic is a well-documented concern. New York DOH has conducted private well assessments and found arsenic to be a priority contaminant. The state's large number of rural private well households in the Hudson Valley, Catskills, Adirondack foothills, and Southern Tier means a significant population faces potential exposure.
New York Arsenic Program
New York DOH monitors arsenic under federal SDWIS and has documented arsenic in private wells across the Adirondacks, Hudson Valley, and western New York on crystalline and sedimentary rock. New York City's surface water supply has low arsenic, but private well owners statewide face natural arsenic risk. New York recommends private well testing every 3–5 years, including arsenic.
Largest New York Water Utilities
No arsenic violations on record in EPA SDWIS for New York utilities in our database. Browse the largest utilities to review their full water quality record.
How Does Arsenic Get Into Drinking Water?
Arsenic in drinking water is almost always naturally occurring — it leaches from arsenic-bearing rocks and minerals into groundwater over time. New England granite, Southwest volcanic geology, and Upper Midwest glacial aquifers are the primary high-risk formations. It has no taste, odor, or color.
Full arsenic overview — geology maps, health effects, all 50 statesWho Should Pay Closest Attention
Private well owners in Columbia, Greene, Ulster, Delaware, Dutchess, Putnam, and Westchester counties in the Hudson Valley, Adirondack foothills counties (Hamilton, Fulton, Herkimer, Hamilton), and Southern Tier counties face the highest arsenic risk.
Private well owners near mining districts or agricultural areas
Residents in states with documented volcanic or geothermal geology
Long-term consumers of water from small groundwater systems
Households in homes built before 1960 with older well casings
Residents whose well water has never been tested for arsenic
Anyone living in a state where bedrock wells are common
How to Check Your Situation in New York
- 1
Identify your water source. If you use a public utility, use the ZIP lookup on this page to find your system and check its compliance record.
- 2
If on public water, review your utility's most recent Consumer Confidence Report (CCR) for arsenic monitoring data. The MCL is 10 ppb — your report should show recent test results.
- 3
If on a private well, order an arsenic test from a New York State Department of Health-certified laboratory. A basic arsenic test costs $15–$40. The state agency website maintains a certified lab list.
- 4
Test your well at the tap — not just at the wellhead. The entire water distribution system within your home can affect water quality.
- 5
If your test shows arsenic above 5 ppb, install certified treatment immediately. If above 10 ppb, do not use the water for drinking or cooking until treatment is installed.
- 6
Retest after installing treatment to confirm it is working as certified. Replace filter media on the manufacturer's schedule — an exhausted filter may not perform as rated.
Treatment Options for Arsenic
Boiling does not remove arsenic — it concentrates it. Standard activated carbon filters (Brita, etc.) do not effectively remove arsenic. Certified treatment is required.
NSF/ANSI Standard 58 — Reverse Osmosis
RO systems certified to NSF/ANSI 58 remove 85–95% of arsenic. Under-sink installation. Most effective for removing multiple contaminants simultaneously. Replace membranes and pre-filters on schedule.
Activated Alumina Filters
Activated alumina is specifically designed for arsenic and fluoride removal. Point-of-use or whole-house options available. Must be certified by NSF International or WQA for arsenic reduction. Requires periodic media regeneration or replacement.
Iron/Manganese Oxidation Filters
Effective for arsenic in iron-rich well water, which is common in the Midwest and New England. Oxidation converts dissolved iron and arsenic to a form that can be filtered out. Best when arsenic is co-occurring with high iron levels.
What does NOT work for arsenic
Standard activated carbon filters (Brita, refrigerator filters, most pitcher filters) do NOT effectively remove arsenic. Boiling concentrates arsenic. Water softeners do not remove arsenic. Only use products with NSF certification specifically for arsenic reduction.
Take Action Now
If you use a private well in New York, test for arsenic — especially if you are in a region with granite, volcanic, or sedimentary geology. A basic arsenic test costs $15–$40 at a state-certified lab.
Public water users: check your utility's Consumer Confidence Report (CCR) for arsenic results. The EPA MCL is 10 ppb — any detection warrants attention.
If arsenic is detected above 10 ppb (or even below it, given MCLG is zero), install an NSF/ANSI 58-certified reverse osmosis system for drinking and cooking water.
Standard carbon filters do NOT remove arsenic — do not rely on a Brita or refrigerator filter for arsenic protection.
Frequently Asked Questions
Related Pages
Arsenic — National Overview
All U.S. utilities with arsenic records
New York State Overview
All utilities and water quality data
New York Well Water Guide
Testing, risks & certified labs for private wells
Reverse Osmosis Guide
Removes 85–95% of arsenic
Best Arsenic Filter Guide
What actually works (carbon doesn't)
PFAS in Drinking Water
The 'forever chemical' contamination overview
All Contaminants
Complete reference library
Data Sources & Provenance
All data on this page is sourced from official U.S. government or public datasets.
Find Your Utility
State Regulator
New York State Department of Health ↗