Non-Transient Non-Community Water System · PWS CT0610563
Haddam-Killingworth High School
Operator location Killingworth, Connecticut - 25% of 85 violations are health-based (upper-third health share (> 23%)); groundwater source; 642 served per SDWIS.
- 642
- People served (this PWS)
- 85
- EPA violations (this PWS)
- 21
- Health-based (this PWS)
- Untested
- UCMR5 (this PWS)
Haddam-Killingworth High School standing, high SDWIS violation third
25% of 85 recorded violations are health-based - upper-third health share (> 23%). Corpus terciles use 29,740 systems serving 500+ (the sitemap cohort). Health-based share 25% is upper-third health share (> 23%). Population rank #25,450 of 29,740 among systems serving 500+.
The verdict
Haddam-Killingworth High School sits in the upper third of the sitemap cohort by violation count (85), so the tables below sample a dense compliance trail rather than a near-clean ledger. Population served is smaller (642; smaller served population (≤ 999)), so each violation row represents a compact service footprint. Health-based share is 25% - most of this ledger is MCL or treatment-technique exceedance. No UCMR5 PFAS test appears for this system in this extract.
- #25,450 of 29,740
- Population · /systems
- #144 of 184
- Population · CT
- 85
- Total EPA violations on record
- 25%
- 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
- Non-Transient Non-Community
- Owner Type
- Local
- Connections
- 1
- County
- Middlesex
- School/Daycare
- Yes
- MCL Violations
- 17
- Monitoring Violations
- 58
- Treatment Tech Violations
- 4
Violation History
Contaminant violations recorded by EPA.
| Contaminant | Category | Count | Latest |
|---|---|---|---|
| Coliform (TCR) | MCL | 17 | 2013 |
| E. COLI | MR | 8 | 2016 |
| Revised Total Coliform Rule | MON | 8 | 2017 |
| Coliform (TCR) | MR | 7 | 2011 |
| Revised Total Coliform Rule | TT | 4 | 2018 |
| Lead and Copper Rule | MR | 4 | 2014 |
| Revised Total Coliform Rule | RPT | 4 | 2018 |
| Methoxychlor | MR | 1 | 2005 |
| Dalapon | MR | 1 | 2005 |
| Glyphosate | MR | 1 | 2005 |
| Di(2-ethylhexyl) phthalate | MR | 1 | 2005 |
| Aldicarb sulfoxide | MR | 1 | 2005 |
| Aldicarb sulfone | MR | 1 | 2005 |
| Atrazine | MR | 1 | 2005 |
| Heptachlor | MR | 1 | 2005 |
| 2,4-D | MR | 1 | 2005 |
| Pentachlorophenol | MR | 1 | 2005 |
| 1,2-DIBROMO-3-CHLOROPROPANE | MR | 1 | 2005 |
| Chlordane | MR | 1 | 2005 |
| Toxaphene | MR | 1 | 2005 |
| OXAMYL | MR | 1 | 2005 |
| Endrin | MR | 1 | 2005 |
| Di(2-ethylhexyl) adipate | MR | 1 | 2005 |
| 2,4,5-TP | MR | 1 | 2005 |
| Heptachlor epoxide | MR | 1 | 2005 |
| Dinoseb | MR | 1 | 2005 |
| Diquat | MR | 1 | 2005 |
| Total Polychlorinated Biphenyls (PCB) | MR | 1 | 2005 |
| Aldicarb | MR | 1 | 2005 |
| HEXACHLOROBENZENE | MR | 1 | 2005 |
Violation Count vs. the National Corpus
Haddam-Killingworth High School has 85 recorded EPA violations, 70% of the 29,740 public water systems serving 500+ people nationwide carry fewer, and 30% carry more. 25% of this system's own violations are health-based (21 of 85), and it ranks #25,450 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)
85 Around the middle fewer violations than 30% 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
Health-based violations on Haddam-Killingworth High School
21 health-based rows in the tables above map to MCL or treatment-technique exceedances, verify each contaminant code on the federal SDWIS report for CT0610563.
Sources: EPA SDWIS
Nationwide peers
85 violations · 642 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 smaller service footprints
Nearest cross-state systems by EPA SDWIS population_served (same 500+ sitemap gate).
What to do with Haddam-Killingworth High School
Use this system's EPA-reported record as a starting filter, not a final verdict.
- See how every tracked system in Connecticut compares on the same EPA violation measures. Connecticut 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.