Is Riddle, OR Tap Water Safe to Drink?
Graded F, with 74 unresolved violations on record. See what was cited — and what it means for your tap. What to do next ↓
42/100
waterverge.com Riddle, OR — Water Quality Report
Riddle's drinking water received a grade of F (42 out of 100), indicating failing water quality. The city's 5 water systems serve approximately 2,014 residents using surface water.
Lead levels were measured at 10.0 ppb (90th percentile), which is within EPA limits but above recommended levels. This system has not yet been tested for PFAS under the EPA UCMR 5 program.
The system has 785 violations on record, including 55 health-based violations. 74 remain unresolved.
What to know about Riddle's water
Riddle ranks #191 out of 213 cities in Oregon for water quality, placing it among the lowest-rated 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.
While lead levels are within EPA limits, they are above the recommended 5 ppb threshold that health organizations consider ideal. A point-of-use filter adds an extra layer of protection.
As a small community water system, Riddle may have fewer resources for advanced treatment technologies and infrastructure upgrades compared to larger utilities.
The system has seen 58 violations in the past five years, suggesting a pattern of compliance challenges that residents should monitor closely.
Water quality score
See methodology →Is Riddle, OR water safe to drink?
Riddle's drinking water has significant quality concerns based on EPA testing data. With a grade of F (42/100), the system has issues across multiple categories. A water filter is recommended for all residents. The city's 5 water systems serve approximately 2,014 residents using surface water (rivers, lakes, or reservoirs).
Recent water quality updates for Riddle
A timeline of significant water quality events, violations, and data updates.
Latest EPA compliance and testing data incorporated into Riddle's water quality assessment. Grade: F (42/100).
Contaminants: Total Haloacetic Acids (HAA5), TTHM, Consumer Confidence Rule.
Contaminants: Surface Water Treatment Rule, Interim Enhanced Surface Water Treatment Rule.
Contaminants: Consumer Confidence Rule.
Federal disaster declaration (FEMA DR-4452). Flood event — may have impacted local water infrastructure.
Federal disaster declaration (FEMA DR-4055). Flood event — may have impacted local water infrastructure.
Key contaminant findings
Based on the most recent EPA sampling data for Riddle's water supply.
Within EPA limits but above the American Academy of Pediatrics recommended level of 1 ppb. An NSF 53-certified filter provides additional protection.
Violation history
Riddle's water system has 785 total violations on record, including 55 health-based violations. 74 remain unresolved. 58 violations were issued in the last 5 years.
Flood & environmental risk
Douglas County has experienced 8 federally declared disasters since 1964. Flooding and severe storms can overwhelm water treatment plants, cause sewage overflows, and introduce agricultural runoff, bacteria, and sediment into drinking water supplies. Local water sources include S Umpqua River, Cow Creek.
Where does Riddle's water come from?
Riddle's drinking water comes from surface water (rivers, lakes, or reservoirs), supplied by 5 water systems serving approximately 2,014 people. Surface water sources are more susceptible to contamination from runoff, industrial discharge, and algal blooms, requiring extensive treatment. Nearby water bodies include S Umpqua River (river), Cow Creek (river).
What Riddle residents can do
Recommended: NSF-certified water filter. This addresses the specific contaminants found in Riddle's water.
Your water utility is required to publish an annual Consumer Confidence Report (CCR) with detailed testing results. Ask for the latest copy or check your utility's website.
Run cold water for 30 seconds before drinking, especially in the morning. Lead and copper leach from household plumbing when water sits in pipes.
Riddle's area has a history of flooding. After severe weather, watch for boil water advisories from your local utility.
Data: EPA SDWIS, UCMR 5 (PFAS), FEMA, NOAA. Last updated May 2026.
Top contaminants to know
View all ↓Violation summary
Violations & advisories
Top industrial polluters within 10 miles of Riddle
Industrial polluters nearby
Reported releases to surface water by facilities near Riddle, ranked by pounds discharged annually.
| Facility | Top chemical | To surface water (lbs/yr) | Distance |
|---|---|---|---|
ROSEBURG FOREST PRODUCTS CO. - RIDDLE PLYWOOD #4 RIDDLE, OR97469 | — | — | 1.2 mi |
ROSEBURG FOREST PRODUCTS CO-EWP FACILITY RIDDLE, OR97469 | — | — | 2.5 mi |
Source: EPA Toxic Release Inventory (TRI) 2023
Superfund sites within 10 miles of Riddle
Superfund sites nearby
Federally tracked hazardous-waste sites on the EPA National Priorities List. Proximity does not necessarily indicate tap-water contamination — the connection depends on hydrology and treatment.
- FORMOSA MINE6.9 mi
Source: EPA Superfund National Priorities List
Drought conditions
D2 — severe droughtDouglas County is currently in D2 (severe drought) per the U.S. Drought Monitor (week of May 5, 2026). Drought can elevate disinfection-byproduct (TTHM/HAA5) levels and taste/odor issues as utilities draw from lower reservoirs.
Source: U.S. Drought Monitor, updated weekly by NDMC, USDA, and NOAA.
Flood & disaster history
Douglas County has experienced 8 federally declared disasters since 1964. Flooding and severe weather can compromise water treatment infrastructure and introduce contaminants into drinking water supplies.
Recommended water filters
Based on contaminants detected in Riddle's water supply, we recommend the following filter types.
Full contaminants report
| Contaminant | Detected Level | EPA Limit | Unit | Category | Status |
|---|---|---|---|---|---|
| Lead (90th percentile) LeadHeavy Metal A toxic heavy metal that can leach into drinking water from older pipes, solder, and fixtures. No amount of lead in water is considered safe. Health EffectsBrain and nervous system damage in children, kidney damage, high blood pressure, and reproductive problems in adults. EPA Limit15 ppb action level Common SourcesCorrosion of lead pipes, lead solder, brass faucets, and household plumbing. | 10.0 | 15 | ppb | Inorganic | Safe |
Lead level trend (90th percentile)
See how Riddle compares by contaminant
Explore where Riddle ranks among all Oregon cities for specific contaminants.
Water source & infrastructure
Where Riddle's water comes from
Riddle's drinking water comes primarily from surface water sources such as rivers, lakes, or reservoirs.
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 local government ownership and serves approximately 2,014 people through 5 water systems.
Water bodies near Riddle
Riddle is located near 2 notable water bodies. As a surface water system, these water bodies may directly influence the city's drinking water supply.
Water systems serving Riddle
| System Name | PWSID | Population | Source |
|---|---|---|---|
| RIDDLE, CITY OF | OR4100706 | 1,224 | SW |
| SOUTH UMPQUA WATER ASSOCIATION | OR4100705 | 575 | SWP |
| DIAMOND LAKE LODGE/RESORT | OR4192104 | 90 | GW |
| LAWSON ACRES WATER ASSOCIATION | OR4100707 | 75 | SWP |
| WINCHESTER RIDGE | OR4101565 | 50 | GW |
How Riddle compares
Full Oregon rankings →Riddle's score of 42/100 is on par with the average of 42/100 among major Oregon cities. It outscores 6 of 10 nearby cities.
Nearby cities
View Oregon rankings →About Riddle, OR
Wikipedia →Riddle is a city in Douglas County, Oregon, United States. As of the 2020 census, Riddle had a population of 1,214.
Learn more about your water
Guides and resources related to Riddle's water quality findings.
Explore water quality across Douglas
Frequently asked questions
Is Riddle, OR tap water safe to drink?
Riddle's water quality earned a grade of F (42/100). Significant issues have been found. A water filter is strongly recommended. The city ranks #191 out of 213 cities tested in Oregon.
What contaminants are in Riddle's water?
Lead was measured at 10.0 ppb (90th percentile). 785 violations are on record.
How is Riddle'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 Riddle?
While lead levels are within EPA limits, a filter adds extra protection. Based on current data, basic filtration should suffice for additional peace of mind.
Where does Riddle's water come from?
Riddle's water is sourced from Surface water. The city has 5 water systems serving approximately 2,014 residents.
What health violations has Riddle's water system had?
Riddle has 55 health-based violations on record. The most recent violation was recorded in October 2025. Health-based violations mean the water exceeded EPA maximum contaminant levels (MCLs) for a regulated substance. 74 violations remain unresolved.
How does Riddle's water compare to other cities?
Riddle ranks #191 out of 213 cities in Oregon (better than 10% of state cities) and #14895 out of 15744 cities nationally (5th percentile). The grade of F reflects the combined assessment of violation history, lead and copper levels, PFAS contamination, and regulatory compliance.