Is Index Water Dept water safe to drink?

Index Water Dept (PWS ID: WA5335600) has 130 recorded violations in the EPA SDWIS database. No PFAS contamination was detected in UCMR5 testing. EPA SDWIS lists this system's service population as 420 people using Groundwater sources.

How many people does Index Water Dept serve?

EPA SDWIS reports that Index Water Dept serves 420 people (this public water system's service population, not the municipal population of Index or any other city). It is a Local-owned system using Groundwater water sources with 129 service connections. The operator address is listed in Index, Washington.

What type of violations does Index Water Dept have?

Index Water Dept has 130 total violations: 18 health-based violations (MCL exceedances or treatment failures), 110 monitoring/reporting violations, and 0 treatment technique violations. Health-based violations indicate contaminant levels exceeded EPA safe limits.

Has PFAS been detected in Index Water Dept water?

No PFAS testing data is available for Index Water Dept under the EPA's UCMR5 monitoring program.

What water source does Index Water Dept use?

Index Water Dept uses Groundwater as its primary water source. It is classified as a Community Water System (CWS), serving residential populations year-round.

Where does this data come from?

All data comes from the EPA Safe Drinking Water Information System (SDWIS) and the UCMR5 PFAS monitoring program. SDWIS tracks compliance for all public water systems regulated under the Safe Drinking Water Act.

How does Index Water Dept's violation count compare nationally?

Index Water Dept has 130 recorded EPA SDWIS violations, fewer than 21% of the 29,740 public water systems serving 500 or more people nationwide (the same sitemap cohort used for the corpus-placement ranking above). 78% of that cohort has fewer violations than Index Water Dept. A system can have zero recorded violations and still be actively monitored, and a high violation count often reflects a system that reports thoroughly, not necessarily one with worse water.

States → Washington

Community Water System · PWS WA5335600

Index Water Dept

Operator location Index, Washington - smaller served population (≤ 999) at 420 people served; 130 SDWIS violations on record from groundwater sources.

Compiled by PlainWater · May 15, 2026

420
People served (this PWS) Smaller third of systems: 130
EPA violations (this PWS) Upper third of systems: 18
Health-based (this PWS) Middle third by health-based share: Untested
UCMR5 (this PWS) No UCMR5 result

Follow published updates (RSS)

Index Water Dept standing, high SDWIS violation third

420 people served (SDWIS) - smaller served population (≤ 999). Corpus terciles use 29,740 systems serving 500+ (the sitemap cohort). Health-based share 14% is middle-third health share (≤ 23%).

The verdict

Index Water Dept sits in the upper third of the sitemap cohort by violation count (130), so the tables below sample a dense compliance trail rather than a near-clean ledger. Population served is smaller (420; smaller served population (≤ 999)), so each violation row represents a compact service footprint. Health-based share is 14% (middle-third health share (≤ 23%)). No UCMR5 PFAS test appears for this system in this extract.

130
Total EPA violations on record: 14%
Health-based (MCL / treatment failure): 420
People served by this PWS (SDWIS): N/A
PFAS compounds detected (UCMR5)

Population ordinals match the sitemap cohort (systems serving 500+, population_served DESC). See methodology · corpus placement.

Water Safety Score

15/100

Index Water Dept

Based on EPA SDWIS violation history and UCMR5 PFAS testing only, not water taste, odor, infrastructure age, or contaminants outside the federally tracked set.

Health-based violations F

EPA SDWIS health-based violations on record (MCL, MRDL, treatment technique)

Monitoring & reporting violations F

112

Non-health SDWIS violations (monitoring, reporting, and other compliance)

PFAS contamination N/A

Not UCMR5-tested

Highest PFAS compound level detected in UCMR5 testing

System Details

System Type: Community
Owner Type: Local
Connections: 129
County: Snohomish
School/Daycare: No
MCL Violations: 18
Monitoring Violations: 110
Treatment Tech Violations: 0

Violation History

Contaminant violations recorded by EPA.

Contaminant	Category	Count	Latest
Coliform (TCR)	MCL	18	1998
Nitrate	MR	14	2013
Lead and Copper Rule	MR	13	2022
Coliform (TCR)	MR	4	2000
Barium	MR	3	2005
Chromium	MR	3	2005
Fluoride	MR	3	2005
Mercury	MR	3	2005
Selenium	MR	3	2005
Arsenic	MR	3	2005
Cadmium	MR	3	2005
Nickel	MR	2	2005
Antimony, Total	MR	2	2005
cis-1,2-Dichloroethylene	MR	2	2017
o-Dichlorobenzene	MR	2	2017
1,1-Dichloroethylene	MR	2	2017
1,2-Dichloroethane	MR	2	2017
Carbon tetrachloride	MR	2	2017
CHLOROBENZENE	MR	2	2017
Benzene	MR	2	2017
Ethylbenzene	MR	2	2017
p-Dichlorobenzene	MR	2	2017
trans-1,2-Dichloroethylene	MR	2	2017
1,1,1-Trichloroethane	MR	2	2017
Toluene	MR	2	2017
Revised Total Coliform Rule	MON	2	2024
Thallium, Total	MR	2	2005
Trichloroethylene	MR	2	2017
Styrene	MR	2	2017
Tetrachloroethylene	MR	2	2017

Violation Count vs. the National Corpus

Index Water Dept has 130 recorded EPA violations, 78% of the 29,740 public water systems serving 500+ people nationwide carry fewer, and 21% carry more. 14% of this system's own violations are health-based (18 of 130), and it ranks unranked by population served among that same cohort.

EPA violations vs. the national water-system corpus

Public water systems serving 500+ people (EPA SDWIS)

130 Higher than most more violations than 78% 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

How many violations vs. how serious, among peer systems

Index Water Dept plotted against 29 peer public water systems (500+ people served), by total violation count (x) and the share of those violations that are health-based (y). The crosshair sits at this sample's own median on each axis. A high violation count does not automatically mean a serious record: most monitoring and reporting violations are minor, not health-based.

30 public water systems (500+ people served), EPA SDWIS current release.

How to read this

Each dot is one public water system; the highlighted dot is Index Water Dept. A system to the right has more recorded violations; a system higher up has a larger share of those violations classified health-based rather than monitoring or reporting.

Rare but serious: few violations, but most of them are health-based.
Frequent, mostly paperwork: many violations, but mostly monitoring or reporting, not health-based.
Clean record: below-median on both counts, the tinted corner.

View all 30 systems as a list

City of Ballinger: 372 violations, 85% health-based
Nooksack Valley Water Association: 16 violations, 31% health-based
Montgomery Co RWD 12: 7 violations, 29% health-based
Irvin Water District #6: 11 violations, 27% health-based
Ticonderoga WD: 47 violations, 26% health-based
Pine Valley Plantation: 37 violations, 24% health-based
McLouth, City Of: 29 violations, 17% health-based
Kipling Oaks 1: 25 violations, 16% health-based
South Deerfield Water Supply District: 96 violations, 16% health-based
Sunset Ridge Water District: 82 violations, 15% health-based
Orange Water Dept: 136 violations, 14% health-based
Index Water Dept: 130 violations, 14% health-based (this system)
Mount Pleasant Water Sys #1: 167 violations, 11% health-based
Lake Gibson Estates: 42 violations, 2% health-based
Benson Culinary Improvement District: 212 violations, 1% health-based
Conemaugh Twp Muni Auth: 567 violations, 1% health-based
Miccosukee Service Plaza: 0 violations, 0% health-based
Brazoria - Fort Bend Counties MUD 3: 0 violations, 0% health-based
Tanglewilde Thompson Place 600: 2 violations, 0% health-based
Center Water Co: 5 violations, 0% health-based
Spring Mills Elem School/Hvs: 9 violations, 0% health-based
Great Bend Industrial Park: 14 violations, 0% health-based
Glen Park Village: 19 violations, 0% health-based
Camp Is-Sho-Da: 22 violations, 0% health-based
Hamilton: 33 violations, 0% health-based
Town of Welaka: 54 violations, 0% health-based
Township of Blairstown Dpw: 61 violations, 0% health-based
McIntosh Water & Fire Pro Authority: 71 violations, 0% health-based
Clarkdale Municipal Water System: 114 violations, 0% health-based
Eureka Water Association: 273 violations, 0% health-based

Population served record for Index Water Dept

EPA SDWIS lists 420 people served and 129 connections for this PWS, confirm the service-area footprint on the federal report before comparing to municipal census totals.

EPA SDWIS · PWS WA5335600 WA primacy agency

Sources: EPA SDWIS · Washington State Department of Health, Office of Drinking Water

Nationwide peers

130 violations · 420 served: nearest cross-state SDWIS matches.

Cross-state systems with comparable violation load

Nearest cross-state community systems (500+ served) by total SDWIS violations on record.

4 peers

What to do with Index Water Dept

Use this system's EPA-reported record as a starting filter, not a final verdict.

See how every tracked system in Washington compares on the same EPA violation measures. Washington 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.

Data sourced from EPA SDWIS and UCMR5 PFAS monitoring data. See our methodology for details. Retrieved and formatted by PlainWater

Compiled by PlainWater, Drinking Water Quality Editorial Process · May 15, 2026

Every figure on PlainWater is rendered directly from EPA SDWIS drinking-water data, no number is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error.