MARIANAPOLIS PREP SCHOOL - ST JOHNS
PWS ID: CT1410051 · THOMPSON, Connecticut 06277
MARIANAPOLIS PREP SCHOOL - ST JOHNS serves 128 people in THOMPSON, Connecticut using Groundwater water sources. It has 424 recorded EPA violations, including 43 health-based violations. No PFAS contamination was detected in UCMR5 testing.
Water Quality Snapshot: MARIANAPOLIS PREP SCHOOL - ST JOHNS
MARIANAPOLIS PREP SCHOOL - ST JOHNS is a private-owned community water system that delivers drinking water to 128 residents in THOMPSON, Connecticut (Windham County) through 1 service connections. Its water is drawn from groundwater sources. EPA's Safe Drinking Water Information System records 424 total violations for this system , of which 43 (10%) are health-based — meaning a contaminant exceeded an EPA Maximum Contaminant Level or a required treatment technique failed. A further 321 monitoring and reporting violations are on file. The most recent violation on record dates to 2024.
The most frequently cited contaminant at this system is Coliform (TCR), recorded in 53 violations (MR). This system has not yet been sampled under EPA's UCMR5 PFAS monitoring program, so no PFAS detection data is available here.
Across Connecticut, EPA tracks 2,332 public water systems serving 2,886,005 people, with 206,662 cumulative violations and 21,779 health-based violations on record. About 94% of systems in the state carry at least one violation, and state-wide the average per system is 88.6 violations. MARIANAPOLIS PREP SCHOOL - ST JOHNS's 424 violations sit above the Connecticut average. Statewide, 40 of 63 UCMR5-tested systems have reported PFAS detections (63.5%). All figures above are sourced directly from EPA SDWIS and UCMR5 public data releases and are updated as EPA publishes new reporting cycles.
System Details
- System Type
- Community
- Owner Type
- Private
- Connections
- 1
- County
- Windham
- School/Daycare
- No
- MCL Violations
- 42
- Monitoring Violations
- 321
- Treatment Tech Violations
- 1
Violation History
Contaminant violations recorded by EPA.
| Contaminant | Category | Count | Latest |
|---|---|---|---|
| Coliform (TCR) | MR | 53 | 2006 |
| Chlorine | MR | 43 | 2007 |
| Coliform (TCR) | MCL | 42 | 2007 |
| Consumer Confidence Rule | Other | 23 | 2019 |
| Gross Alpha, Excl. Radon and U | MR | 18 | 2006 |
| Combined Radium (-226 and -228) | MR | 18 | 2006 |
| Combined Uranium | MR | 18 | 2006 |
| Public Notice | Other | 7 | 2008 |
| BHC-GAMMA | MR | 4 | 2007 |
| Toxaphene | MR | 4 | 2007 |
| Aldicarb sulfoxide | MR | 4 | 2007 |
| Carbofuran | MR | 4 | 2007 |
| Atrazine | MR | 4 | 2007 |
| LASSO | MR | 4 | 2007 |
| 2,4-D | MR | 4 | 2007 |
| 2,4,5-TP | MR | 4 | 2007 |
| Pentachlorophenol | MR | 4 | 2007 |
| Chlordane | MR | 4 | 2007 |
| Diquat | MR | 4 | 2007 |
| Di(2-ethylhexyl) phthalate | MR | 4 | 2007 |
| Dinoseb | MR | 4 | 2007 |
| HEXACHLOROBENZENE | MR | 4 | 2007 |
| Benzo(a)pyrene | MR | 4 | 2007 |
| Heptachlor | MR | 4 | 2007 |
| ETHYLENE DIBROMIDE | MR | 4 | 2007 |
| 1,2-DIBROMO-3-CHLOROPROPANE | MR | 4 | 2007 |
| Picloram | MR | 4 | 2007 |
| Dalapon | MR | 4 | 2007 |
| Aldicarb | MR | 4 | 2007 |
| OXAMYL | MR | 4 | 2007 |
Verify This Water System
The figures above are aggregated from EPA's public databases. To verify the underlying records — or to file a complaint, request a Consumer Confidence Report, or check current monitoring status — go directly to the federal and state regulators that enforce the Safe Drinking Water Act for MARIANAPOLIS PREP SCHOOL - ST JOHNS.
EPA SDWIS — Federal Reports
EPA's Safe Drinking Water Information System (SDWIS) holds the federal compliance record for every regulated public water system. Open the system-level report by PWS ID:
View PWS ID CT1410051 on SDWISSource: EPA SDWIS Federal Reports Search
Connecticut Drinking Water Authority
Connecticut's primacy agency administers the Safe Drinking Water Act locally. Search EPA SDWIS for the current state contact, or use the state's public health or environment department portal.
Find CT regulator via EPA SDWISViolation Timeline
Each row links to the EPA SDWIS public record for verification. Cross-reference the contaminant code on EPA's federal report to see violation dates, return-to-compliance status, and enforcement actions.
| Year (latest) | Contaminant | Category | Count | EPA Record |
|---|---|---|---|---|
| 2024 | LEAD AND COPPER RULE REVISIONS | TT | 1 | SDWIS / CT1410051 / 5200 |
| 2024 | LEAD AND COPPER RULE REVISIONS | RPT | 1 | SDWIS / CT1410051 / 5200 |
| 2019 | Consumer Confidence Rule | Other | 23 | SDWIS / CT1410051 / 7000 |
| 2018 | Revised Total Coliform Rule | MON | 4 | SDWIS / CT1410051 / 8000 |
| 2008 | Public Notice | Other | 7 | SDWIS / CT1410051 / 7500 |
| 2007 | Chlorine | MR | 43 | SDWIS / CT1410051 / 0999 |
| 2007 | Coliform (TCR) | MCL | 42 | SDWIS / CT1410051 / 3100 |
| 2007 | BHC-GAMMA | MR | 4 | SDWIS / CT1410051 / 2010 |
| 2007 | Toxaphene | MR | 4 | SDWIS / CT1410051 / 2020 |
| 2007 | Aldicarb sulfoxide | MR | 4 | SDWIS / CT1410051 / 2043 |
| 2007 | Carbofuran | MR | 4 | SDWIS / CT1410051 / 2046 |
| 2007 | Atrazine | MR | 4 | SDWIS / CT1410051 / 2050 |
| 2007 | LASSO | MR | 4 | SDWIS / CT1410051 / 2051 |
| 2007 | 2,4-D | MR | 4 | SDWIS / CT1410051 / 2105 |
| 2007 | 2,4,5-TP | MR | 4 | SDWIS / CT1410051 / 2110 |
How MARIANAPOLIS PREP SCHOOL - ST JOHNS Compares
Cross-reference this system's record against state averages and the federal MCL framework for context.
| Metric | MARIANAPOLIS PREP SCHOOL - ST JOHNS | Connecticut avg | Federal benchmark |
|---|---|---|---|
| Total violations | 424 | 88.6 | SDWA compliance — any non-zero count is a recorded breach |
| Health-based violations | 43 | 9.3 | Indicates a contaminant exceeded a federal MCL |
| PFAS detection | None | 63.5% | EPA final rule (2024): PFOA/PFOS MCL = 4.0 ppt |
| Population served | 128 | 1,238 | Sizing context for compliance burden |
Sources: EPA SDWIS and EPA National Primary Drinking Water Regulations (40 CFR Part 141). State averages computed across 2,332 regulated public water systems in Connecticut.
Federal MCL reference — Safe Drinking Water Act thresholds ▼
| Contaminant | Federal MCL / Action Level | Note |
|---|---|---|
| Lead | 0 mg/L (Action Level: 0.015 mg/L) | Lead and Copper Rule treatment technique |
| Arsenic | 0.010 mg/L (10 ppb) | Health-based MCL since 2006 |
| Total Coliform | Treatment technique (RTCR) | Indicator organism, monitoring trigger |
| PFOA / PFOS (PFAS) | 4.0 ppt each (final 2024 rule) | Compliance deadline 2029 |
| Nitrate (as N) | 10 mg/L | Acute health risk for infants |
Frequently Asked Questions
Is MARIANAPOLIS PREP SCHOOL - ST JOHNS water safe to drink? ▼
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What type of violations does MARIANAPOLIS PREP SCHOOL - ST JOHNS have? ▼
Has PFAS been detected in MARIANAPOLIS PREP SCHOOL - ST JOHNS water? ▼
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Related Data for Connecticut
Read our methodology — how this data is sourced, computed, and verified.