Community Water System · PWS 090400001
Topawa Intertie
Operator location Sells, EPA Region 9 — Tribal Water Systems - lower-third violation load (≤ 21 violations) with 17 EPA violations; groundwater source; 1,318 served (PWS-level, not municipal population).
- 1,318
- People served (this PWS)
- 17
- EPA violations (this PWS)
- 1
- Health-based (this PWS)
- Untested
- UCMR5 (this PWS)
Topawa Intertie standing, low SDWIS violation third
17 EPA SDWIS violations on record - lower-third violation load (≤ 21 violations). Corpus terciles use 29,740 systems serving 500+ (the sitemap cohort). Health-based share 6% is middle-third health share (≤ 23%). Population rank #17,023 of 29,740 among systems serving 500+.
The verdict
Topawa Intertie is in the lower third by violation count (17; lower-third violation load (≤ 21 violations)). A low count does not mean the system is unmonitored - monitoring and reporting violations still appear in SDWIS. Population served is mid-pack at 1,318 (mid served population (≤ 3,309)). Health-based share is 6% (middle-third health share (≤ 23%)). No UCMR5 PFAS test appears for this system in this extract.
- #17,023 of 29,740
- Population · /systems
- #77 of 129
- Population · 09
- 17
- Total EPA violations on record
- 6%
- 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
- 292
- School/Daycare
- No
- MCL Violations
- 1
- Monitoring Violations
- 13
- Treatment Tech Violations
- 0
Violation History
Contaminant violations recorded by EPA.
| Contaminant | Category | Count | Latest |
|---|---|---|---|
| Nitrate | MR | 2 | 2005 |
| Cadmium | MR | 1 | 2004 |
| Arsenic | MR | 1 | 2004 |
| Barium | MR | 1 | 2004 |
| Chromium | MR | 1 | 2004 |
| Fluoride | MR | 1 | 2004 |
| Selenium | MR | 1 | 2004 |
| TTHM | MR | 1 | 2004 |
| Total Haloacetic Acids (HAA5) | MR | 1 | 2004 |
| E. COLI | MR | 1 | 2019 |
| Asbestos | MR | 1 | 2004 |
| Mercury | MR | 1 | 2004 |
| Coliform (TCR) | MCL | 1 | 2000 |
Violation Count vs. the National Corpus
Topawa Intertie has 17 recorded EPA violations, 28% of the 29,740 public water systems serving 500+ people nationwide carry fewer, and 71% carry more. 6% of this system's own violations are health-based (1 of 17), and it ranks #17,023 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)
17 Lower than most fewer violations than 71% 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
SDWIS compliance record for Topawa Intertie
17 violations on record for 090400001; use EPA SDWIS to confirm return-to-compliance dates and monitoring categories.
Sources: EPA SDWIS
Nationwide peers
17 violations · 1,318 served: nearest cross-state SDWIS matches.
Cross-state systems with similarly light violation ledgers
Nearest cross-state community systems (500+ served) by total SDWIS violations on record.
Cross-state systems near this population served
Nearest cross-state systems by EPA SDWIS population_served (same 500+ sitemap gate).
What to do with Topawa Intertie
Use this system's EPA-reported record as a starting filter, not a final verdict.
- See how every tracked system in EPA Region 9 — Tribal Water Systems compares on the same EPA violation measures. EPA Region 9 — 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.