Community Water System · PWS NY5103700
Dering Harbor Water District
Operator location Shelter Island Heights, New York - smaller served population (≤ 999) at 14 people served; 107 SDWIS violations on record from groundwater sources.
- 14
- People served (this PWS)
- 107
- EPA violations (this PWS)
- 2
- Health-based (this PWS)
- Untested
- UCMR5 (this PWS)
Dering Harbor Water District standing, high SDWIS violation third
14 people served (SDWIS) - smaller served population (≤ 999). Corpus terciles use 29,740 systems serving 500+ (the sitemap cohort). Health-based share 2% is middle-third health share (≤ 23%).
The verdict
Dering Harbor Water District sits in the upper third of the sitemap cohort by violation count (107), so the tables below sample a dense compliance trail rather than a near-clean ledger. Population served is smaller (14; smaller served population (≤ 999)), so each violation row represents a compact service footprint. Health-based share is 2% (middle-third health share (≤ 23%)). No UCMR5 PFAS test appears for this system in this extract.
- 107
- Total EPA violations on record
- 2%
- Health-based (MCL / treatment failure)
- 14
- People served by this PWS (SDWIS)
- N/A
- PFAS compounds detected (UCMR5)
Population ordinals match the sitemap cohort (systems serving 500+, population_served DESC). See methodology · corpus placement.
Based on EPA SDWIS violation history and UCMR5 PFAS testing only, not water taste, odor, infrastructure age, or contaminants outside the federally tracked set.
System Details
- System Type
- Community
- Owner Type
- Local
- Connections
- 37
- County
- Suffolk
- School/Daycare
- No
- MCL Violations
- 2
- Monitoring Violations
- 90
- Treatment Tech Violations
- 0
Violation History
Contaminant violations recorded by EPA.
| Contaminant | Category | Count | Latest |
|---|---|---|---|
| Consumer Confidence Rule | Other | 8 | 2008 |
| Dalapon | MR | 3 | 2004 |
| Di(2-ethylhexyl) adipate | MR | 3 | 2004 |
| Picloram | MR | 3 | 2004 |
| Dinoseb | MR | 3 | 2004 |
| Hexachlorocyclopentadiene | MR | 3 | 2004 |
| Carbofuran | MR | 3 | 2004 |
| Aldicarb | MR | 3 | 2004 |
| LASSO | MR | 3 | 2004 |
| Heptachlor epoxide | MR | 3 | 2004 |
| HEXACHLOROBENZENE | MR | 3 | 2004 |
| Benzo(a)pyrene | MR | 3 | 2004 |
| Total Polychlorinated Biphenyls (PCB) | MR | 3 | 2004 |
| Mercury | MR | 3 | 2014 |
| Endrin | MR | 3 | 2004 |
| Di(2-ethylhexyl) phthalate | MR | 3 | 2004 |
| Chlordane | MR | 3 | 2004 |
| BHC-GAMMA | MR | 3 | 2004 |
| Total Haloacetic Acids (HAA5) | MR | 3 | 2013 |
| Aldicarb sulfoxide | MR | 3 | 2004 |
| Pentachlorophenol | MR | 3 | 2004 |
| Methoxychlor | MR | 3 | 2004 |
| Heptachlor | MR | 3 | 2004 |
| OXAMYL | MR | 3 | 2004 |
| Simazine | MR | 3 | 2004 |
| ETHYLENE DIBROMIDE | MR | 3 | 2004 |
| Aldicarb sulfone | MR | 3 | 2004 |
| Toxaphene | MR | 3 | 2004 |
| Atrazine | MR | 3 | 2004 |
| 2,4,5-TP | MR | 3 | 2004 |
Violation Count vs. the National Corpus
Dering Harbor Water District has 107 recorded EPA violations, 75% of the 29,740 public water systems serving 500+ people nationwide carry fewer, and 25% carry more. 2% of this system's own violations are health-based (2 of 107), and it ranks unranked by population served among that same cohort.
EPA violations vs. the national water-system corpus
Public water systems serving 500+ people (EPA SDWIS)
107 Around the middle fewer violations than 25% of 29,740 water systems
the national water-system corpus, bucketed by value
Each bar is a band; taller bars hold more water systems. The dashed line + filled bar mark this entry. Hover or tap any bar for its full count and share, and where it sits relative to this entry.
Source EPA SDWIS · 2026-05-15
How many violations vs. how serious, among peer systems
Dering Harbor Water District plotted against 29 peer public water systems (500+ people served), by total violation count (x) and the share of those violations that are health-based (y). The crosshair sits at this sample's own median on each axis. A high violation count does not automatically mean a serious record: most monitoring and reporting violations are minor, not health-based.
Violation volume vs. health-based share
Population served record for Dering Harbor Water District
EPA SDWIS lists 14 people served and 37 connections for this PWS, confirm the service-area footprint on the federal report before comparing to municipal census totals.
Sources: EPA SDWIS · New York State Department of Health, Public Water Systems
Nationwide peers
107 violations · 14 served: nearest cross-state SDWIS matches.
Cross-state systems with comparable violation load
Nearest cross-state community systems (500+ served) by total SDWIS violations on record.
What to do with Dering Harbor Water District
Use this system's EPA-reported record as a starting filter, not a final verdict.
- See how every tracked system in New York compares on the same EPA violation measures. New York systems
- Check whether PFAS was detected at this system under UCMR5 testing. PFAS guide
- Find and compare another public water system by name or PWSID. Search systems
EPA SDWIS and UCMR5 figures are informational only, not a substitute for a certified lab test of your own tap water.