What is COLIPHAGE in drinking water?

COLIPHAGE averages 4.2 violations per affected system (2,523 total / 601 systems) in the EPA SDWIS extract.

How many water systems have COLIPHAGE violations?

601 systems sit in the mid footprint band (mid footprint (≤ 8,691 systems)).

Are COLIPHAGE violations dangerous?

In this extract, 0% are health-based. Recorded findings are monitoring/reporting class, not MCL exceedances.

Where does COLIPHAGE sit in the national contaminant ledger?

#95 of 157 indexable contaminants by violation volume - middle-third volume (≤ 49,133 violations), mid load (≤ 5.8 violations per affected system).

Where does this contaminant data come from?

EPA Safe Drinking Water Information System (SDWIS) quarterly extracts. Counts are cumulative compliance records, not a live risk score for a single tap.

Contaminants →

EPA SDWIS

COLIPHAGE in Drinking Water

Compiled by PlainWater · May 15, 2026

4.2 violations per affected system (2,523 across 601) - mid load (≤ 5.8 violations per affected system).

Browse all SDWIS contaminants →

EPA contaminant code: 3028

Total Violations

2,523

Systems Affected

601

Health-Based %

Violations / System

4.2

COLIPHAGE standing, mid-volume SDWIS third

COLIPHAGE lands in the middle third by violation volume (2,523), large enough for peer comparisons but not one of the handful of analytes that dominate the fleet-wide SDWIS ledger. Load sits mid-pack at 4.2 violations per affected system (mid load (≤ 5.8 violations per affected system)). None of the recorded COLIPHAGE violations in this extract are classified health-based; the trail is procedural. Among 157 indexable contaminants, this page is #95 by violation volume. Utilities listed below are ranked by cumulative violation count for this analyte; pair that with population served to gauge household exposure scale.

Nationwide similar contaminants

Nearest by violation volume

Chloramine (2,449) Cryptosporidium (2,446) Stage 2 Disinfectants and Disinfection Byproducts Rule (3,102) Chlorite (3,255)

Nearest by systems affected

Gross Beta Particle Activity (792 systems) Long Term 2 Enhanced Surface Water Treatment Rule (871 systems) Coliform (Pre-TCR) (174 systems) Bromate (140 systems)

COLIPHAGE: monitoring/reporting trail

0% health-based · 100.0% monitoring/reporting across 2,523 records.

Health-based (0%) Monitoring/Reporting (100.0%)

Most Affected Water Systems

System	State	Violations	Population
Coos Golf Club	OR	44	30
Diamond Lake Gas Station	OR	40	45
Sprague River Water Assn	OR	34	60
Dundee, City Of	OR	32	2,960
Monrovia North	OR	29	175
Surprise Valley RV Park	OR	28	45
Bigfoot Acres	OR	28	60
Sunshine Plaza	OR	28	200
Flying Eagle Market & Video	OR	28	100
Salmon Run Golf Course	OR	28	100
Maple Elsie Water Service	OR	27	100
Prineville, City Of	OR	26	11,000
Labish Village Wtr Commission	OR	24	452
Area 61	OR	23	260
Oakridge, City Of	OR	21	3,310
Coe Bonneville Dam	OR	21	109
Country View Mh Estates	OR	20	132
Lutheran Retreat	OR	20	35
Umpqua Ranch Coop	OR	19	161
Laurel Ridge MHP	OR	19	70
Foley Lakes Mobile Home Park	OR	18	300
Camp Cooper Bsa	OR	18	25
Coe Cottage Grove	OR	18	750
Westhills Country Store	OR	17	75
Trappist Abbey	OR	16	29
Dairy Creek Tavern	OR	16	50
Sunset Hwy Bar & Grill	OR	15	50
Bridge Water District	OR	14	150
Country Garden Estates MHP	OR	14	175
Columbia Hills HOA	OR	14	84

Context: understanding water quality data · is my water safe?

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

Disclaimer: This information is provided for informational purposes only and does not constitute professional advice. Data is sourced from the EPA Safe Drinking Water Information System (SDWIS). Consult a qualified professional before making decisions based on this data.

Read our methodology - how this data is sourced, computed, and verified.

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