Community Water System · PWS 083090050
Assiniboine & Sioux Rural Water System
Operator location Poplar, EPA Region 8 — Tribal Water Systems - 61% of 18 violations are health-based (upper-third health share (> 23%)); surface water source; 1,726 served per SDWIS.
- 1,726
- People served (this PWS)
- 18
- EPA violations (this PWS)
- 11
- Health-based (this PWS)
- Untested
- UCMR5 (this PWS)
Assiniboine & Sioux Rural Water System standing, low SDWIS violation third
61% of 18 recorded violations are health-based - upper-third health share (> 23%). Corpus terciles use 29,740 systems serving 500+ (the sitemap cohort). Health-based share 61% is upper-third health share (> 23%). Population rank #14,785 of 29,740 among systems serving 500+.
The verdict
Assiniboine & Sioux Rural Water System is in the lower third by violation count (18; 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 1,726 (mid served population (≤ 3,309)). Health-based share is 61% - most of this ledger is MCL or treatment-technique exceedance. No UCMR5 PFAS test appears for this system in this extract.
- #14,785 of 29,740
- Population · /systems
- #25 of 55
- Population · 08
- 18
- Total EPA violations on record
- 61%
- 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
- Federal
- Connections
- 245
- School/Daycare
- No
- MCL Violations
- 0
- Monitoring Violations
- 7
- Treatment Tech Violations
- 11
Violation History
Contaminant violations recorded by EPA.
| Contaminant | Category | Count | Latest |
|---|---|---|---|
| Interim Enhanced Surface Water Treatment Rule | TT | 6 | 2013 |
| CARBON, TOTAL | TT | 5 | 2015 |
| Total Haloacetic Acids (HAA5) | MR | 3 | 2025 |
| TTHM | MR | 3 | 2025 |
| Revised Total Coliform Rule | MON | 1 | 2018 |
Violation Count vs. the National Corpus
Assiniboine & Sioux Rural Water System has 18 recorded EPA violations, 29% of the 29,740 public water systems serving 500+ people nationwide carry fewer, and 70% carry more. 61% of this system's own violations are health-based (11 of 18), and it ranks #14,785 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)
18 Lower than most fewer violations than 70% 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 Assiniboine & Sioux Rural Water System
11 health-based rows in the tables above map to MCL or treatment-technique exceedances, verify each contaminant code on the federal SDWIS report for 083090050.
Sources: EPA SDWIS
Nationwide peers
18 violations · 1,726 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 Assiniboine & Sioux Rural Water System
Use this system's EPA-reported record as a starting filter, not a final verdict.
- See how every tracked system in EPA Region 8 — Tribal Water Systems compares on the same EPA violation measures. EPA Region 8 — 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.