Community Water System · PWS NY5903442
New Castle/Stanwood W.D.
Operator location Chappaqua, New York - larger served population (> 3,309) at 17,116 people served; 105 SDWIS violations on record from surface water sources.
- 17,116
- People served (this PWS)
- 105
- EPA violations (this PWS)
- 4
- Health-based (this PWS)
- No PFAS
- UCMR5 (this PWS)
New Castle/Stanwood W.D. standing, high SDWIS violation third
17,116 people served (SDWIS) - larger served population (> 3,309). Corpus terciles use 29,740 systems serving 500+ (the sitemap cohort). Health-based share 4% is middle-third health share (≤ 23%). UCMR5: UCMR5 tested, none detected. Population rank #3,086 of 29,740 among systems serving 500+.
The verdict
New Castle/Stanwood W.D. sits in the upper third of the sitemap cohort by violation count (105), so the tables below sample a dense compliance trail rather than a near-clean ledger. Population served is large (17,116; larger served population (> 3,309)), so household exposure scale sits behind the violation mix. Health-based share is 4% (middle-third health share (≤ 23%)). UCMR5 tested this system and reported no PFAS above the minimum reporting level.
- #3,086 of 29,740
- Population · /systems
- #107 of 1,204
- Population · NY
- 105
- Total EPA violations on record
- 4%
- Health-based (MCL / treatment failure)
Population ordinals match the sitemap cohort (systems serving 500+, population_served DESC). See methodology · corpus placement.
System Details
- System Type
- Community
- Owner Type
- Local
- Connections
- 5,183
- County
- Westchester
- School/Daycare
- No
- MCL Violations
- 4
- Monitoring Violations
- 95
- Treatment Tech Violations
- 0
Violation History
Contaminant violations recorded by EPA.
| Contaminant | Category | Count | Latest |
|---|---|---|---|
| TTHM | MR | 8 | 2018 |
| Total Haloacetic Acids (HAA5) | MR | 8 | 2018 |
| Beryllium, Total | MR | 5 | 2002 |
| Selenium | MR | 5 | 2002 |
| Thallium, Total | MR | 5 | 2002 |
| Cadmium | MR | 5 | 2002 |
| Nitrate-Nitrite | MR | 5 | 2002 |
| Barium | MR | 5 | 2002 |
| Chromium | MR | 5 | 2002 |
| Fluoride | MR | 5 | 2002 |
| Nickel | MR | 5 | 2002 |
| Nitrite | MR | 5 | 2002 |
| Mercury | MR | 5 | 2002 |
| CYANIDE | MR | 5 | 2002 |
| Antimony, Total | MR | 5 | 2002 |
| Nitrate | MR | 5 | 2002 |
| Arsenic | MR | 5 | 2002 |
| Coliform (TCR) | MR | 4 | 2007 |
| Coliform (TCR) | MCL | 4 | 2009 |
Violation Count vs. the National Corpus
New Castle/Stanwood W.D. has 105 recorded EPA violations, 74% of the 29,740 public water systems serving 500+ people nationwide carry fewer, and 26% carry more. 4% of this system's own violations are health-based (4 of 105), and it ranks #3,086 of 29,740 by population served among that same cohort.
EPA violations vs. the national water-system corpus
Public water systems serving 500+ people (EPA SDWIS)
105 Around the middle fewer violations than 26% 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
PFAS Testing Results (UCMR5)
Results from EPA's Fifth Unregulated Contaminant Monitoring Rule. 0 of 116 samples detected PFAS.
| Contaminant | Date | Result | MRL | Status |
|---|---|---|---|---|
| 9Cl-PF3ONS | 9/12/2023 | <2.00 ppt | 2.00 ppt | Not Detected |
| 11Cl-PF3OUdS | 9/12/2023 | <5.00 ppt | 5.00 ppt | Not Detected |
| PFBS | 9/12/2023 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFHpA | 9/12/2023 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFUnA | 9/12/2023 | <2.00 ppt | 2.00 ppt | Not Detected |
| PFNA | 9/12/2023 | <4.00 ppt | 4.00 ppt | Not Detected |
| PFOS | 9/12/2023 | <4.00 ppt | 4.00 ppt | Not Detected |
| PFOA | 9/12/2023 | <4.00 ppt | 4.00 ppt | Not Detected |
| PFDA | 9/12/2023 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFDoA | 9/12/2023 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFHxA | 9/12/2023 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFHxS | 9/12/2023 | <3.00 ppt | 3.00 ppt | Not Detected |
| 8:2 FTS | 9/12/2023 | <5.00 ppt | 5.00 ppt | Not Detected |
| PFBA | 9/12/2023 | <5.00 ppt | 5.00 ppt | Not Detected |
| PFHpS | 9/12/2023 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFPeS | 9/12/2023 | <4.00 ppt | 4.00 ppt | Not Detected |
| NFDHA | 9/12/2023 | <20.00 ppt | 20.00 ppt | Not Detected |
| PFEESA | 9/12/2023 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFMBA | 9/12/2023 | <3.00 ppt | 3.00 ppt | Not Detected |
| HFPO-DA | 9/12/2023 | <5.00 ppt | 5.00 ppt | Not Detected |
| PFMPA | 9/12/2023 | <4.00 ppt | 4.00 ppt | Not Detected |
| ADONA | 9/12/2023 | <3.00 ppt | 3.00 ppt | Not Detected |
| 4:2 FTS | 9/12/2023 | <3.00 ppt | 3.00 ppt | Not Detected |
| 6:2 FTS | 9/12/2023 | <5.00 ppt | 5.00 ppt | Not Detected |
| PFTA | 9/12/2023 | <8.00 ppt | 8.00 ppt | Not Detected |
| PFTrDA | 9/12/2023 | <7.00 ppt | 7.00 ppt | Not Detected |
| NEtFOSAA | 9/12/2023 | <5.00 ppt | 5.00 ppt | Not Detected |
| NMeFOSAA | 9/12/2023 | <6.00 ppt | 6.00 ppt | Not Detected |
| PFPeA | 9/12/2023 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFBA | 6/20/2023 | <5.00 ppt | 5.00 ppt | Not Detected |
| HFPO-DA | 6/20/2023 | <5.00 ppt | 5.00 ppt | Not Detected |
| ADONA | 6/20/2023 | <3.00 ppt | 3.00 ppt | Not Detected |
| 9Cl-PF3ONS | 6/20/2023 | <2.00 ppt | 2.00 ppt | Not Detected |
| PFUnA | 6/20/2023 | <2.00 ppt | 2.00 ppt | Not Detected |
| 6:2 FTS | 6/20/2023 | <5.00 ppt | 5.00 ppt | Not Detected |
| PFPeS | 6/20/2023 | <4.00 ppt | 4.00 ppt | Not Detected |
| PFDA | 6/20/2023 | <3.00 ppt | 3.00 ppt | Not Detected |
| 4:2 FTS | 6/20/2023 | <3.00 ppt | 3.00 ppt | Not Detected |
| 8:2 FTS | 6/20/2023 | <5.00 ppt | 5.00 ppt | Not Detected |
| PFMPA | 6/20/2023 | <4.00 ppt | 4.00 ppt | Not Detected |
| PFPeA | 6/20/2023 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFMBA | 6/20/2023 | <3.00 ppt | 3.00 ppt | Not Detected |
| NFDHA | 6/20/2023 | <20.00 ppt | 20.00 ppt | Not Detected |
| PFHxA | 6/20/2023 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFHpS | 6/20/2023 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFOA | 6/20/2023 | <4.00 ppt | 4.00 ppt | Not Detected |
| PFEESA | 6/20/2023 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFTrDA | 6/20/2023 | <7.00 ppt | 7.00 ppt | Not Detected |
| 11Cl-PF3OUdS | 6/20/2023 | <5.00 ppt | 5.00 ppt | Not Detected |
| PFOS | 6/20/2023 | <4.00 ppt | 4.00 ppt | Not Detected |
Population served record for New Castle/Stanwood W.D.
EPA SDWIS lists 17,116 people served and 5,183 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
105 violations · 17,116 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.
Cross-state systems with similar served population
Nearest cross-state systems by EPA SDWIS population_served (same 500+ sitemap gate).
What to do with New Castle/Stanwood W.D.
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.