Non-Transient Non-Community Water System · PWS CA1000280
Sierra High School
Operator location Tollhouse, California - smaller served population (≤ 999) at 720 people served; 16 SDWIS violations on record from groundwater sources.
- 720
- People served (this PWS)
- 16
- EPA violations (this PWS)
- 1
- Health-based (this PWS)
- Untested
- UCMR5 (this PWS)
Sierra High School standing, low SDWIS violation third
720 people served (SDWIS) - smaller served population (≤ 999). Corpus terciles use 29,740 systems serving 500+ (the sitemap cohort). Health-based share 6% is middle-third health share (≤ 23%). Population rank #23,937 of 29,740 among systems serving 500+.
The verdict
Sierra High School is in the lower third by violation count (16; 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 smaller (720; smaller served population (≤ 999)), so each violation row represents a compact service footprint. Health-based share is 6% (middle-third health share (≤ 23%)). No UCMR5 PFAS test appears for this system in this extract.
- #23,937 of 29,740
- Population · /systems
- #1,383 of 1,701
- Population · CA
- 16
- 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
- Non-Transient Non-Community
- Owner Type
- Local
- Connections
- 26
- County
- Fresno
- School/Daycare
- Yes
- MCL Violations
- 0
- Monitoring Violations
- 10
- Treatment Tech Violations
- 1
Violation History
Contaminant violations recorded by EPA.
| Contaminant | Category | Count | Latest |
|---|---|---|---|
| Coliform (TCR) | MR | 2 | 2008 |
| Total Haloacetic Acids (HAA5) | MR | 2 | 2016 |
| TTHM | MR | 2 | 2016 |
| Nitrate | MR | 2 | 2021 |
| Stage 2 Disinfectants and Disinfection Byproducts Rule | Other | 2 | 2016 |
| Revised Total Coliform Rule | MON | 2 | 2020 |
| LEAD AND COPPER RULE REVISIONS | RPT | 1 | 2024 |
| LEAD AND COPPER RULE REVISIONS | TT | 1 | 2024 |
Violation Count vs. the National Corpus
Sierra High School has 16 recorded EPA violations, 26% of the 29,740 public water systems serving 500+ people nationwide carry fewer, and 72% carry more. 6% of this system's own violations are health-based (1 of 16), and it ranks #23,937 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)
16 Lower than most fewer violations than 72% 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
Population served record for Sierra High School
EPA SDWIS lists 720 people served and 26 connections for this PWS, confirm the service-area footprint on the federal report before comparing to municipal census totals.
Sources: EPA SDWIS · California State Water Resources Control Board, Division of Drinking Water
Nationwide peers
16 violations · 720 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 with smaller service footprints
Nearest cross-state systems by EPA SDWIS population_served (same 500+ sitemap gate).
What to do with Sierra High School
Use this system's EPA-reported record as a starting filter, not a final verdict.
- See how every tracked system in California compares on the same EPA violation measures. California 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.