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HILLTOP IMPROVEMENT DISTRICT

PWS ID: OR4100237 · COTTAGE GROVE, Oregon 97424

HILLTOP IMPROVEMENT DISTRICT serves 45 people in COTTAGE GROVE, Oregon using Groundwater water sources. It has 615 recorded EPA violations, including 67 health-based violations. No PFAS contamination was detected in UCMR5 testing.

Water Quality Snapshot: HILLTOP IMPROVEMENT DISTRICT

HILLTOP IMPROVEMENT DISTRICT is a private-owned community water system that delivers drinking water to 45 residents in COTTAGE GROVE, Oregon (Lane County) through 19 service connections. Its water is drawn from groundwater sources. EPA's Safe Drinking Water Information System records 615 total violations for this system , of which 67 (11%) are health-based — meaning a contaminant exceeded an EPA Maximum Contaminant Level or a required treatment technique failed. A further 533 monitoring and reporting violations are on file. The most recent violation on record dates to 2023.

The most frequently cited contaminant at this system is Coliform (TCR), recorded in 149 violations (MR). This system has not yet been sampled under EPA's UCMR5 PFAS monitoring program, so no PFAS detection data is available here.

Across Oregon, EPA tracks 2,518 public water systems serving 4,005,242 people, with 206,659 cumulative violations and 20,339 health-based violations on record. About 99% of systems in the state carry at least one violation, and state-wide the average per system is 82.1 violations. HILLTOP IMPROVEMENT DISTRICT's 615 violations sit above the Oregon average. Statewide, 30 of 125 UCMR5-tested systems have reported PFAS detections (24%). All figures above are sourced directly from EPA SDWIS and UCMR5 public data releases and are updated as EPA publishes new reporting cycles.

Population Served
45
Total Violations
615
Health-Based Violations
67
Water Source
Groundwater

System Details

System Type
Community
Owner Type
Private
Connections
19
County
Lane
School/Daycare
No
MCL Violations
67
Monitoring Violations
533
Treatment Tech Violations
0

Violation History

Contaminant violations recorded by EPA.

Contaminant Category Count Latest
Coliform (TCR) MR 149 2009
Arsenic MCL 35 2010
Coliform (TCR) MCL 32 2009
Diquat MR 6 1996
Endrin MR 6 1996
ETHYLENE DIBROMIDE MR 6 1996
Heptachlor epoxide MR 6 1996
HEXACHLOROBENZENE MR 6 1996
Hexachlorocyclopentadiene MR 6 1996
Methoxychlor MR 6 1996
Di(2-ethylhexyl) phthalate MR 6 1996
Picloram MR 6 1996
Simazine MR 6 1996
Toxaphene MR 6 1996
OXAMYL MR 6 1996
1,1-Dichloroethylene MR 6 1996
1,1,1-Trichloroethane MR 6 1996
1,1,2-Trichloroethane MR 6 1996
1,2-Dichloropropane MR 6 1996
1,2,4-Trichlorobenzene MR 6 1996
cis-1,2-Dichloroethylene MR 6 1996
CHLOROBENZENE MR 6 1996
Styrene MR 6 1996
Tetrachloroethylene MR 6 1996
Toluene MR 6 1996
Trichloroethylene MR 6 1996
Barium MR 6 1996
Cadmium MR 6 1996
Chromium MR 6 1996
Selenium MR 6 1996

Verify This Water System

The figures above are aggregated from EPA's public databases. To verify the underlying records — or to file a complaint, request a Consumer Confidence Report, or check current monitoring status — go directly to the federal and state regulators that enforce the Safe Drinking Water Act for HILLTOP IMPROVEMENT DISTRICT.

Federal Source of Truth

EPA SDWIS — Federal Reports

EPA's Safe Drinking Water Information System (SDWIS) holds the federal compliance record for every regulated public water system. Open the system-level report by PWS ID:

View PWS ID OR4100237 on SDWIS

Source: EPA SDWIS Federal Reports Search

State Regulator

Oregon Drinking Water Authority

Oregon's primacy agency administers the Safe Drinking Water Act locally. Search EPA SDWIS for the current state contact, or use the state's public health or environment department portal.

Find OR regulator via EPA SDWIS

Violation Timeline

Each row links to the EPA SDWIS public record for verification. Cross-reference the contaminant code on EPA's federal report to see violation dates, return-to-compliance status, and enforcement actions.

Year (latest) Contaminant Category Count EPA Record
2023 Consumer Confidence Rule Other 5 SDWIS / OR4100237 / 7000
2023 Lead and Copper Rule MR 4 SDWIS / OR4100237 / 5000
2011 Public Notice Other 4 SDWIS / OR4100237 / 7500
2010 Arsenic MCL 35 SDWIS / OR4100237 / 1005
2009 Coliform (TCR) MR 149 SDWIS / OR4100237 / 3100
2009 Coliform (TCR) MCL 32 SDWIS / OR4100237 / 3100
1998 Nitrate MR 6 SDWIS / OR4100237 / 1040
1996 Diquat MR 6 SDWIS / OR4100237 / 2032
1996 Endrin MR 6 SDWIS / OR4100237 / 2005
1996 ETHYLENE DIBROMIDE MR 6 SDWIS / OR4100237 / 2946
1996 Heptachlor epoxide MR 6 SDWIS / OR4100237 / 2067
1996 HEXACHLOROBENZENE MR 6 SDWIS / OR4100237 / 2274
1996 Hexachlorocyclopentadiene MR 6 SDWIS / OR4100237 / 2042
1996 Methoxychlor MR 6 SDWIS / OR4100237 / 2015
1996 Di(2-ethylhexyl) phthalate MR 6 SDWIS / OR4100237 / 2039

How HILLTOP IMPROVEMENT DISTRICT Compares

Cross-reference this system's record against state averages and the federal MCL framework for context.

Metric HILLTOP IMPROVEMENT DISTRICT Oregon avg Federal benchmark
Total violations 615 82.1 SDWA compliance — any non-zero count is a recorded breach
Health-based violations 67 8.1 Indicates a contaminant exceeded a federal MCL
PFAS detection None 24% EPA final rule (2024): PFOA/PFOS MCL = 4.0 ppt
Population served 45 1,591 Sizing context for compliance burden

Sources: EPA SDWIS and EPA National Primary Drinking Water Regulations (40 CFR Part 141). State averages computed across 2,518 regulated public water systems in Oregon.

Federal MCL reference — Safe Drinking Water Act thresholds ▼
Contaminant Federal MCL / Action Level Note
Lead 0 mg/L (Action Level: 0.015 mg/L) Lead and Copper Rule treatment technique
Arsenic 0.010 mg/L (10 ppb) Health-based MCL since 2006
Total Coliform Treatment technique (RTCR) Indicator organism, monitoring trigger
PFOA / PFOS (PFAS) 4.0 ppt each (final 2024 rule) Compliance deadline 2029
Nitrate (as N) 10 mg/L Acute health risk for infants

Frequently Asked Questions

Is HILLTOP IMPROVEMENT DISTRICT water safe to drink? ▼
HILLTOP IMPROVEMENT DISTRICT (PWS ID: OR4100237) has 615 recorded violations in the EPA SDWIS database. No PFAS contamination was detected in UCMR5 testing. This system serves 45 people using Groundwater sources.
How many people does HILLTOP IMPROVEMENT DISTRICT serve? ▼
HILLTOP IMPROVEMENT DISTRICT serves 45 people in COTTAGE GROVE, Oregon. It is a Private-owned system using Groundwater water sources with 19 service connections.
What type of violations does HILLTOP IMPROVEMENT DISTRICT have? ▼
HILLTOP IMPROVEMENT DISTRICT has 615 total violations: 67 health-based violations (MCL exceedances or treatment failures), 533 monitoring/reporting violations, and 0 treatment technique violations. Health-based violations indicate contaminant levels exceeded EPA safe limits.
Has PFAS been detected in HILLTOP IMPROVEMENT DISTRICT water? ▼
No PFAS testing data is available for HILLTOP IMPROVEMENT DISTRICT under the EPA's UCMR5 monitoring program.
What water source does HILLTOP IMPROVEMENT DISTRICT use? ▼
HILLTOP IMPROVEMENT DISTRICT 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.

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Data Sources: EPA Safe Drinking Water Information System (SDWIS), Q4 2025. This data is provided for informational purposes only.

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

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