City water profile

Water hardness in Shelter Island

Find official utility reports, understand hardness, and check the water system serving your home in Shelter Island, New York.

Utility-reported hardness

Not yet available

Check your provider and source →

State comparison: Unavailable
Evidence comparison rank: —
Matched utilities: 3
Active health records: 0

Your tap water

What does the utility report?

Match the utility name to your water bill. These results describe the utility’s water, not a test at your home. A ZIP can include several water systems.

Utility hardness unavailable in this index

Nearby river or groundwater samples cannot tell us the hardness coming out of your tap. Ask your water provider for total hardness as CaCO₃, or test it at home.

Find an official utility report →

Convert a hardness result →Test your tap →

Match the name on your water bill

Your utility’s measurements and compliance records

These are possible serving systems. A record for one system does not apply to every home in this ZIP. Confirm your provider before interpreting a measurement or notice. Federal records can lag current utility notices.

EPA snapshot: 2026Q2. Historical window begins Jan 1, 2021.

Shelter Island Heights Association

NY5103243 · Groundwater · 500 people served system-wide

The system names this served city; Census place overlap links the city to this ZCTA.

No active health-based record in this imported snapshot

Find this utility’s official report →

Measurements (2)

An action level is a regulatory trigger, not a pass/fail health boundary. A reported zero is the value in the source record and does not establish that lead is absent at your tap.

Lead (90th percentile)

EPA SDWIS Lead and Copper Rule samples

Below action level

Reported level: 0.0011 mg/L
Action level: 0.015 mg/L

7% of the listed benchmark

Monitoring period: Jan 1, 2021 to Dec 31, 2023

Copper (90th percentile)

EPA SDWIS Lead and Copper Rule samples

Above action level

Reported level: 1.85 mg/L
Action level: 1.3 mg/L

142% of the listed benchmark

Monitoring period: Jan 1, 2004 to Dec 31, 2006

Violation history (29)

Imported violation history for Shelter Island Heights Association
Rule	Status	Period
LEAD AND COPPER RULE REVISIONS	Resolved	Oct 17, 2024 to Jan 3, 2025
Di(2-ethylhexyl) adipate	Resolved	Jan 1, 2023 to Dec 31, 2023
Simazine	Resolved	Jan 1, 2023 to Dec 31, 2023
Di(2-ethylhexyl) phthalate	Resolved	Jan 1, 2023 to Dec 31, 2023
Picloram	Resolved	Jan 1, 2023 to Dec 31, 2023
Dinoseb	Resolved	Jan 1, 2023 to Dec 31, 2023
Atrazine	Resolved	Jan 1, 2023 to Dec 31, 2023
LASSO	Resolved	Jan 1, 2023 to Dec 31, 2023
Heptachlor epoxide	Resolved	Jan 1, 2023 to Dec 31, 2023
2,4,5-TP	Resolved	Jan 1, 2023 to Dec 31, 2023
HEXACHLOROBENZENE	Resolved	Jan 1, 2023 to Dec 31, 2023
Benzo(a)pyrene	Resolved	Jan 1, 2023 to Dec 31, 2023
Total Polychlorinated Biphenyls (PCB)	Resolved	Jan 1, 2023 to Dec 31, 2023
ETHYLENE DIBROMIDE	Resolved	Jan 1, 2023 to Dec 31, 2023
Pentachlorophenol	Resolved	Jan 1, 2023 to Dec 31, 2023
BHC-GAMMA	Resolved	Jan 1, 2023 to Dec 31, 2023
Toxaphene	Resolved	Jan 1, 2023 to Dec 31, 2023
Aldicarb sulfoxide	Resolved	Jan 1, 2023 to Dec 31, 2023
Heptachlor	Resolved	Jan 1, 2023 to Dec 31, 2023
Aldicarb	Resolved	Jan 1, 2023 to Dec 31, 2023
2,4-D	Resolved	Jan 1, 2023 to Dec 31, 2023
Endrin	Resolved	Jan 1, 2023 to Dec 31, 2023
Dalapon	Resolved	Jan 1, 2023 to Dec 31, 2023
Carbofuran	Resolved	Jan 1, 2023 to Dec 31, 2023
Chlordane	Resolved	Jan 1, 2023 to Dec 31, 2023
Hexachlorocyclopentadiene	Resolved	Jan 1, 2023 to Dec 31, 2023
OXAMYL	Resolved	Jan 1, 2023 to Dec 31, 2023
Aldicarb sulfone	Resolved	Jan 1, 2023 to Dec 31, 2023
Methoxychlor	Resolved	Jan 1, 2023 to Dec 31, 2023

West Neck Water District

NY5110623 · Groundwater · 100 people served system-wide

The system names this served city; Census place overlap links the city to this ZCTA.

No active health-based record in this imported snapshot

Find this utility’s official report →

Measurements (2)

An action level is a regulatory trigger, not a pass/fail health boundary. A reported zero is the value in the source record and does not establish that lead is absent at your tap.

Lead (90th percentile)

EPA SDWIS Lead and Copper Rule samples

Below action level

Reported level: 0.0013 mg/L
Action level: 0.015 mg/L

9% of the listed benchmark

Monitoring period: Jan 1, 2023 to Dec 31, 2025

Copper (90th percentile)

EPA SDWIS Lead and Copper Rule samples

Above action level

Reported level: 4.4 mg/L
Action level: 1.3 mg/L

338% of the listed benchmark

Monitoring period: Jul 1, 1993 to Dec 31, 1993

Violation history (0)

No record returned in this imported window. This is not a guarantee of tap-water safety.

Dering Harbor Water District

NY5103700 · Groundwater · 14 people served system-wide

The system names this served city; Census place overlap links the city to this ZCTA.

No active health-based record in this imported snapshot

Find this utility’s official report →

Measurements (1)

An action level is a regulatory trigger, not a pass/fail health boundary. A reported zero is the value in the source record and does not establish that lead is absent at your tap.

Lead (90th percentile)

EPA SDWIS Lead and Copper Rule samples

Below action level

Reported level: 0.0012 mg/L
Action level: 0.015 mg/L

8% of the listed benchmark

Monitoring period: Jan 1, 2023 to Dec 31, 2023

Violation history (0)

No record returned in this imported window. This is not a guarantee of tap-water safety.

City summary

What the indexed records say

Shelter Island has 1 published ZIP profile across Suffolk County. The regional-evidence median is 61 PPM. The city does not meet the stricter comparison standard.

Because only one ZIP is represented, the city median and range are the same local estimate. It should not be read as multiple independent samples across the community.

Hardness distribution

How local ZIP estimates compare

Soft0 ZIPs

Moderately hard1 ZIP

Hard0 ZIPs

Very hard0 ZIPs

1 of 1 ZIP profiles have a hardness estimate. Bars count ZIP profiles, not households or laboratory samples.

Evidence quality

Distance, dates, and confidence

Median nearest distance: 1.6 miles
Profiles with evidence: 1/1

Confidence labels

High: 1Moderate: 0Low: 0

Observation window: Sep 7, 2016 to Dec 2, 2025.

ZIP directory

Water reports in Shelter Island

Open a ZIP for site-level provenance and measurements.

ZIP code

11964

Moderately Hard

60.8 PPM

Nearest site: 1.6 mi
Confidence: High

View full ZIP evidence →

Practical next steps

Move from index to evidence

1. Open your ZIP. Check distance, dates, confidence, and the associated utility.
2. Read the current CCR. Confirm source water, detections, limits, ranges, and notices.
3. Use a measured hardness result. Confirm health concerns or treatment sizing with the right method.

Continue comparing

Other New York communities

Brookhaven

Suffolk County

41 PPM median

Islip

Suffolk County

38 PPM median

Riverhead

Suffolk County

48 PPM median

Smithtown

Suffolk County

36 PPM median

Southold

Suffolk County

54 PPM median

Croghan

Lewis County

61 PPM median

Search all 502 New York cities →

Questions people ask

About water in Shelter Island

Is the water hard?

Check the utility-reported result above when available. Nearby environmental samples cannot establish tap-water hardness. Ask your provider or test your tap.

Is the tap water safe?

Compliance history is utility-wide and cannot guarantee conditions at every tap. Check current notices and test when address-specific evidence is needed.

Do I need treatment?

Choose treatment only after confirming the problem at the property. A softener targets hardness; contaminant treatment requires a matching, verified performance claim.