Community Water System · PWS 063500116
San Ildefonso Pueblo
Operator location Santa Fe, EPA Region 6 — Tribal Water Systems - 36% of 56 violations are health-based (upper-third health share (> 23%)); groundwater source; 608 served per SDWIS.
- 608
- People served (this PWS)
- 56
- EPA violations (this PWS)
- 20
- Health-based (this PWS)
- Untested
- UCMR5 (this PWS)
San Ildefonso Pueblo standing, mid SDWIS violation third
36% of 56 recorded violations are health-based - upper-third health share (> 23%). Corpus terciles use 29,740 systems serving 500+ (the sitemap cohort). Health-based share 36% is upper-third health share (> 23%). Population rank #25,987 of 29,740 among systems serving 500+.
The verdict
San Ildefonso Pueblo lands in the middle third by violation volume (56), large enough for peer comparisons without matching the fleet's heaviest ledgers. Population served is smaller (608; smaller served population (≤ 999)), so each violation row represents a compact service footprint. Health-based share is 36% - most of this ledger is MCL or treatment-technique exceedance. No UCMR5 PFAS test appears for this system in this extract.
- #25,987 of 29,740
- Population · /systems
- #53 of 54
- Population · 06
- 56
- Total EPA violations on record
- 36%
- 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
- Native American
- Connections
- 257
- School/Daycare
- No
- MCL Violations
- 2
- Monitoring Violations
- 22
- Treatment Tech Violations
- 18
Violation History
Contaminant violations recorded by EPA.
| Contaminant | Category | Count | Latest |
|---|---|---|---|
| Coliform (TCR) | MR | 16 | 2008 |
| Groundwater Rule | TT | 16 | 2018 |
| Consumer Confidence Rule | Other | 9 | 2005 |
| Lead and Copper Rule | MR | 2 | 2008 |
| Total Haloacetic Acids (HAA5) | MR | 2 | 2015 |
| Stage 1 Disinfectants and Disinfection Byproducts Rule | TT | 2 | 2019 |
| Coliform (TCR) | MCL | 2 | 1997 |
| TTHM | MR | 2 | 2015 |
| Public Notice | Other | 1 | 2013 |
Violation Count vs. the National Corpus
San Ildefonso Pueblo has 56 recorded EPA violations, 60% of the 29,740 public water systems serving 500+ people nationwide carry fewer, and 40% carry more. 36% of this system's own violations are health-based (20 of 56), and it ranks #25,987 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)
56 Around the middle fewer violations than 40% 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 San Ildefonso Pueblo
20 health-based rows in the tables above map to MCL or treatment-technique exceedances, verify each contaminant code on the federal SDWIS report for 063500116.
Sources: EPA SDWIS
Nationwide peers
56 violations · 608 served: nearest cross-state SDWIS matches.
Cross-state systems near this violation count
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 San Ildefonso Pueblo
Use this system's EPA-reported record as a starting filter, not a final verdict.
- See how every tracked system in EPA Region 6 — Tribal Water Systems compares on the same EPA violation measures. EPA Region 6 — Tribal Water Systems 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.