Community Water System · PWS TX1012913
Harris County MUD 321
Operator location Houston, Texas - 0% of 33 violations are health-based (lower-third health share (≤ 1%)); surface water source; 882 served per SDWIS.
- 882
- People served (this PWS)
- 33
- EPA violations (this PWS)
- 0
- Health-based (this PWS)
- Untested
- UCMR5 (this PWS)
Harris County MUD 321 standing, mid SDWIS violation third
0% of 33 recorded violations are health-based - lower-third health share (≤ 1%). Corpus terciles use 29,740 systems serving 500+ (the sitemap cohort). Health-based share 0% is lower-third health share (≤ 1%). Population rank #21,384 of 29,740 among systems serving 500+.
The verdict
Harris County MUD 321 lands in the middle third by violation volume (33), large enough for peer comparisons without matching the fleet's heaviest ledgers. Population served is smaller (882; smaller served population (≤ 999)), so each violation row represents a compact service footprint. Health-based share is only 0% - almost all of this trail is monitoring or reporting. No UCMR5 PFAS test appears for this system in this extract.
- #21,384 of 29,740
- Population · /systems
- #2,410 of 3,040
- Population · TX
- 33
- Total EPA violations on record
- 0%
- 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
- Local
- Connections
- 294
- County
- Harris
- School/Daycare
- No
- MCL Violations
- 0
- Monitoring Violations
- 25
- Treatment Tech Violations
- 0
Violation History
Contaminant violations recorded by EPA.
| Contaminant | Category | Count | Latest |
|---|---|---|---|
| Lead and Copper Rule | MR | 13 | 2016 |
| Revised Total Coliform Rule | MON | 4 | 2023 |
| Public Notice | Other | 4 | 2015 |
| Total Haloacetic Acids (HAA5) | MR | 4 | 2013 |
| TTHM | MR | 4 | 2013 |
Violation Count vs. the National Corpus
Harris County MUD 321 has 33 recorded EPA violations, 45% of the 29,740 public water systems serving 500+ people nationwide carry fewer, and 54% carry more. 0% of this system's own violations are health-based (0 of 33), and it ranks #21,384 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)
33 Lower than most fewer violations than 54% 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 Harris County MUD 321
0 health-based rows in the tables above map to MCL or treatment-technique exceedances, verify each contaminant code on the federal SDWIS report for TX1012913.
Sources: EPA SDWIS · Texas Commission on Environmental Quality (TCEQ) - Drinking Water Watch
Nationwide peers
33 violations · 882 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 Harris County MUD 321
Use this system's EPA-reported record as a starting filter, not a final verdict.
- See how every tracked system in Texas compares on the same EPA violation measures. Texas 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.