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WaterVerge

Water quality report · updated Jul 2026

Is Gaston, OR Tap Water Safe to Drink?

Graded D — but Copper was detected above EPA limits. Here's what's in the water and how to remove it. What to do ↓

1 contaminant over a legal limit
1.4 ppb lead, 90th percentile · low
32 unresolved violations
3K people served by 3 water systems

PWSID OR4100313 · moderate data confidence · private utility

Reviewed by WaterVerge Editorial Team · Last updated July 2026
D 45 / 100

#158 of 213Oregon cities
How we grade →

01The verdict: is Gaston water safe?

Gaston's drinking water has significant quality concerns based on EPA testing data. With a grade of D (45/100), the system has issues across multiple categories. A water filter is recommended for all residents. The city's 3 water systems serve approximately 3,325 residents using surface water (rivers, lakes, or reservoirs).

The concern

Copper is over its legal limit

Measured at 2.19 mg/L against the EPA Action Level of 1.3 mg/L. The ledger below shows how far over — and which filter removes it.

See the measurement ↓
The good news

Lead is well under the limit

90th-percentile lead is 1.4 ppb — beneath the 15 ppb federal action level and under the 5 ppb watch threshold.

See the trend ↓
Keep watching

44 violations in the last five years

Recent compliance history is the best predictor of future problems — the year-by-year record is below.

See the record ↓

Gaston's drinking water received a grade of D (45 out of 100), indicating poor water quality. The city's 3 water systems serve approximately 3,325 residents using purchased surface water.

Lead levels were measured at 1.4 ppb (90th percentile), well within EPA limits. This system has not yet been tested for PFAS under the EPA UCMR 5 program. The system has 268 violations on record, including 13 health-based violations. 32 remain unresolved.

Gaston ranks #158 out of 213 cities in Oregon for water quality, placing it below average in the state. The city draws from surface water sources, which are more susceptible to seasonal runoff and agricultural contamination, requiring extensive multi-barrier treatment including coagulation, filtration, and disinfection. The system has seen 44 violations in the past five years, suggesting a pattern of compliance challenges that residents should monitor closely.

How the 45/100 breaks down Methodology →
ViolationsHistorical violation record including health-based and monitoring violations.
0 / 45F
Lead & CopperLead at 1.4 ppb (90th percentile).
16 / 20B
ContaminantsPFAS + legacy contaminant analysis.
17 / 20B
ComplianceMonitoring and reporting compliance with EPA regulations.
8 / 10B
Source RiskWater source: Purchased surface water.
4 / 5B

02What's in Gaston's water

Every contaminant flagged in Gaston, on one shared scale: distance to its own legal limit. The red line is the limit — anything past it is out of compliance, and the closer a bar gets, the less headroom the system has.

2 detections · sorted by % of legal limit
Over the limit Elevated — watch Within limits
0 50% LEGAL LIMIT 150%

Over Limit — EPA Action Level: 1.3 mg/L

Exceeds the EPA action level. Copper leaches from household plumbing — flush taps for 30 seconds before drinking, and consider a certified filter.
Exceeds Limit What to do →
2 contaminants tested under EPA SDWIS, LCR and UCMR programs · 2 detected · not yet tested for PFAS under UCMR 5

Full contaminants report

Contaminant Detected Level EPA Limit Unit Category Status
Lead (90th percentile) 1.4 15 ppb Inorganic Safe
Copper (90th percentile) 2.19 1.3 mg/L Inorganic Over Limit
Data source: EPA SDWIS, UCMR 5, local utility CCR.

03Gaston's ten-year track record

Each box is one year. A green check means no EPA violations; a numbered badge counts that year's violations — red if any were health-based, amber if they were monitoring or paperwork issues. The system has 268 violations on record, including 13 health-based violations. 32 remain unresolved.

1 of the last ten years was clean. The numbered years had EPA violations — red when any were health-based, amber when they were paperwork or missed-testing issues.

4 health-based in 10 yrs 123 monitoring & paperwork 16 still unresolved
UpdateWater quality data updatedLatest EPA compliance and testing data incorporated into Gaston's water quality assessment. Grade: D (45/100).
Violation1 drinking water violation recordedContaminants: Groundwater Rule.Resolved
Violation2 drinking water violations recordedContaminants: Groundwater Rule, Revised Total Coliform Rule.Resolved
Violation6 drinking water violations recorded1 health-based. Contaminants: TTHM, Total Haloacetic Acids (HAA5), Consumer Confidence Rule.Open
DisasterHURRICANE KATRINA EVACUATIONFederal disaster declaration (FEMA DR-3228). Coastal Storm event — may have impacted local water infrastructure.
DisasterHIGH WINDS, SEVERE STORMS AND FLOODINGFederal disaster declaration (FEMA DR-1099). Flood event — may have impacted local water infrastructure.
Lead, 90th percentileppb · lower is better
05101520EPA action level · 15 ppb1993 — 9 ppb1994 — 3 ppb1995 — 11 ppb1996 — 9 ppb1997 — 5 ppb2003 — 1 ppb2004 — 3 ppb2005 — 5 ppb2010 — 4.5 ppb2013 — 8 ppb2014 — 2 ppb2016 — 7 ppb2017 — 5 ppb2020 — 1 ppb2021 — 2 ppb2024 — 1.3 ppb2026 — 0 ppb9019931997201020172026

Down 9 ppb since 1993. Latest reading: 0 ppb (2026) — 0% of the action level. Sampled at higher-risk homes (90th percentile).

Copper, 90th percentilemg/L · lower is better
0123EPA action level · 1.3 mg/L1994 — 1.4 mg/L2013 — 2.2 mg/L1.42.219942013

Up 0.80 mg/L since 1994. The latest reading (2.2 mg/L, 2013) is over the action level. Sampled at higher-risk homes (90th percentile).

04Where Gaston's water comes from

Gaston's drinking water comes primarily from surface water sources such as rivers, lakes, or reservoirs.

Source

Purchased Surface Water

Rivers, lakes, or reservoirs — more exposed to runoff, agriculture, and seasonal swings than groundwater.

Treatment

Wholesale supplier

Multi-barrier treatment: coagulation, sedimentation, filtration, and disinfection to meet EPA standards.

Distribution

3 systems

3 water systems, operated under private ownership.

Delivery

3,325 people

Residents served across Gaston's service area.

Surface water systems require multi-stage treatment including coagulation, sedimentation, filtration, and disinfection to meet EPA Safe Drinking Water Act standards. These sources can be impacted by seasonal changes, stormwater runoff, upstream agriculture, and industrial discharge. The system is operated by private ownership and serves approximately 3,325 people through 3 water systems.

System namePWSIDPopulationSource
LA WATER CO-OP OR4100313 2,500 Purchased Surface Water
GASTON, CITY OF OR4100312 625 Purchased Surface Water
LAURELWOOD WATER USERS OR4100315 200 Groundwater

Water bodies near Gaston

Wapato Canal · stream Wapato Creek · river Scoggins · river Tualatin River · river Scoggins Creek · river

As a surface-water system, these water bodies may directly influence Gaston's drinking water supply.

05Pressure on Gaston's watershed

Outside forces that shape what reaches the treatment plant. None of these is a verdict on the tap by itself — but each adds pressure worth knowing about.

Industrial discharge

Present — monitored

5 facilities within 10 miles reported 1 lb released to surface water in the latest EPA Toxics Release Inventory. Proximity doesn't equal tap contamination — treatment and hydrology decide — but it's pressure on the watershed.

TTM TECHNOLOGIES N.A. LLC — copper and copper compounds 0 lb · 6.2 mi
WESTAK OF OREGON — copper compounds 0 lb · 7.0 mi
STIMSON LUMBER CO. - GASTON — lead 0 lb · 3.2 mi
+ 2 more facilities

Flood & storm history

Recurring — declared disasters

5 federal disaster declarations on record for Washington County. Flooding and severe storms can overwhelm treatment plants, cause sewage overflows, and push runoff into supplies.

HURRICANE KATRINA EVACUATION Sep 2005 · DR-3228
HIGH WINDS, SEVERE STORMS AND FLOODING Feb 1996 · DR-1099
SEVERE STORMS, SNOWMELT & FLOODING Jan 1974 · DR-413

06How Gaston compares

Scores for nearby Oregon cities on one line, with the average marked.

Gaston (this city)
45 · D
Salem
43.6 · F
Bend
41 · F
Beaverton
40.7 · F
Portland
39.4 · F
Eugene
28 · F

dashed line = Oregon average (42/100)

Gaston scores 45/100on par with the Oregon average of 42/100. It outscores 9 of 10 nearby cities. Full Oregon rankings →

Washington water quality rankings
Compare all cities in the county — grades, violations, and contaminant data side by side.

07What to do at home

Steps matched to what testing actually found in Gaston's water — not generic advice.

Because of copper

Filter drinking & cooking water

NSF-certified water filter. Copper exceeds the EPA action level of 1.3 mg/L

Compare tested filters →
Know your report

Read your utility's annual report

Every utility must publish a yearly Consumer Confidence Report with its own testing results. It pairs well with the independent data on this page.

How to read a CCR →
Stay informed

Watch for Gaston alerts

This area has a history of flood declarations — after severe weather, watch for boil-water advisories from the utility, and check the live alerts on this page.

All water alerts →

Frequently asked questions

Is Gaston, OR tap water safe to drink?

Gaston's water quality earned a grade of D (45/100). Significant issues have been found. A water filter is strongly recommended. The city ranks #158 out of 213 cities tested in Oregon.

What contaminants are in Gaston's water?

Lead was measured at 1.4 ppb (90th percentile). 268 violations are on record.

How is Gaston's water quality grade calculated?

The grade is based on four factors: violation history (40%), lead and copper levels (25%), PFAS contamination (25%), and regulatory compliance (10%). The score is also adjusted based on how complete the available data is. See our methodology page for full details.

Do I need a water filter in Gaston?

Based on current data, basic filtration should suffice for additional peace of mind.

Where does Gaston's water come from?

Gaston's water is sourced from Purchased surface water. The city has 3 water systems serving approximately 3,325 residents.

What health violations has Gaston's water system had?

Gaston has 13 health-based violations on record. The most recent violation was recorded in December 2025. Health-based violations mean the water exceeded EPA maximum contaminant levels (MCLs) for a regulated substance. 32 violations remain unresolved.

How does Gaston's water compare to other cities?

Gaston ranks #158 out of 213 cities in Oregon (better than 26% of state cities) and #13955 out of 15382 cities nationally (9th percentile). The grade of D reflects the combined assessment of violation history, lead and copper levels, PFAS contamination, and regulatory compliance.

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About Gaston, OR: Median household income $91,000 · median age 41.7 · 75% homeowners · 10.8% college educated. Service area: 1 ZIP code across Washington.
Show ZIP codes 97119
Sources: EPA SDWIS & ECHO · UCMR 3–5 · Lead & Copper Rule samples · EPA TRI · U.S. Drought Monitor · FEMA declarations. Data last updated Jul 2026. Analysis by the WaterVerge Editorial Team · methodology.