Is Twisp, WA Tap Water Safe to Drink?
Graded A with no contaminants above EPA limits. Here's everything we tested and how Twisp ranks. What to do next ↓
93.5/100
waterverge.com Twisp, WA — Water Quality Report
Twisp's drinking water received a grade of A (93.5 out of 100), indicating excellent water quality. The city's 1 water system serves approximately 1,044 residents using groundwater.
Lead levels were measured at 1.1 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 42 violations on record, including 6 health-based violations. All violations have been resolved.
What to know about Twisp's water
Twisp ranks #13 out of 294 cities in Washington for water quality, placing it one of the best in the state.
Twisp relies on groundwater, which is generally less vulnerable to surface contamination but can be affected by naturally occurring minerals like arsenic and nitrate, as well as agricultural and industrial runoff.
As a small community water system, Twisp may have fewer resources for advanced treatment technologies and infrastructure upgrades compared to larger utilities.
Water quality score
See methodology →Is Twisp, WA water safe to drink?
Based on EPA testing data, Twisp's tap water is generally safe to drink. The water system earned a grade of A (93.5/100), meeting federal drinking water standards across key contaminant categories. The city's 1 water system serves approximately 1,044 residents using groundwater (wells).
Recent water quality updates for Twisp
A timeline of significant water quality events, violations, and data updates.
Latest EPA compliance and testing data incorporated into Twisp's water quality assessment. Grade: A (93.5/100).
Federal disaster declaration (FEMA DR-4650). Flood event — may have impacted local water infrastructure.
Contaminants: Nitrate.
Contaminants: Revised Total Coliform Rule.
Contaminants: Nitrate.
Federal disaster declaration (FEMA DR-3227). Coastal Storm event — may have impacted local water infrastructure.
Key contaminant findings
Based on the most recent EPA sampling data for Twisp's water supply.
Well within EPA limits.
Violation history
Twisp's water system has 42 total violations on record, including 6 health-based violations. All violations have been resolved. 2 violations were issued in the last 5 years.
Flood & environmental risk
Okanogan County has experienced 4 federally declared disasters since 1972. 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 Chewuch River, Methow River, Twisp River.
Where does Twisp's water come from?
Twisp's drinking water comes from groundwater (wells), supplied by 1 water system serving approximately 1,044 people. Groundwater is generally less susceptible to surface contamination but can contain naturally occurring contaminants like arsenic, radon, and nitrate. Nearby water bodies include Chewuch River (river), Methow River (river), Twisp River (river).
What Twisp residents can do
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.
Twisp'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
Drought conditions
D1 — moderate droughtOkanogan County is currently in D1 (moderate 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
Okanogan County has experienced 4 federally declared disasters since 1972. Flooding and severe weather can compromise water treatment infrastructure and introduce contaminants into drinking water supplies.
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. | 1.1 | 15 | ppb | Inorganic | Safe |
Lead level trend (90th percentile)
See how Twisp compares by contaminant
Explore where Twisp ranks among all Washington cities for specific contaminants.
Water source & infrastructure
Where Twisp's water comes from
Twisp's drinking water is drawn from underground aquifers through wells.
Groundwater is naturally filtered through rock and soil layers, generally requiring less treatment than surface water. However, it can contain naturally occurring contaminants like arsenic, radon, and minerals.
Agricultural activity, septic systems, and industrial operations near well fields can introduce nitrates, pesticides, and volatile organic compounds.
The system is operated by local government ownership and serves approximately 1,044 people through 1 water system.
Water bodies near Twisp
Twisp is located near 3 notable water bodies. These water bodies contribute to the regional watershed and may indirectly affect groundwater quality.
Water systems serving Twisp
| System Name | PWSID | Population | Source |
|---|---|---|---|
| TWISP TOWN OF | WA5390050 | 1,044 | GW |
How Twisp compares
Full Washington rankings →Twisp's score of 93.5/100 is above the average of 53/100 among major Washington cities. It outscores 10 of 10 nearby cities.
Nearby cities
View Washington rankings →About Twisp, WA
Learn more about your water
Guides and resources related to Twisp's water quality findings.
Explore water quality across Okanogan
Frequently asked questions
Is Twisp, WA tap water safe to drink?
Twisp's water quality earned a grade of A (93.5/100). The water generally meets EPA standards and is considered safe for consumption. The city ranks #13 out of 294 cities tested in Washington.
What contaminants are in Twisp's water?
Lead was measured at 1.1 ppb (90th percentile). 42 violations are on record.
How is Twisp'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 Twisp?
Based on current data, basic filtration should suffice for additional peace of mind.
Where does Twisp's water come from?
Twisp's water is sourced from Groundwater. The city has 1 water system serving approximately 1,044 residents.
What health violations has Twisp's water system had?
Twisp has 6 health-based violations on record. The most recent violation was recorded in January 2022. Health-based violations mean the water exceeded EPA maximum contaminant levels (MCLs) for a regulated substance. All health violations have been resolved.
Is Twisp's groundwater at risk of contamination?
Twisp uses groundwater, which can be affected by naturally occurring contaminants like arsenic, radon, and nitrate, as well as agricultural runoff and industrial activity. The system has 42 violations on record that may relate to groundwater quality. Groundwater systems are generally less susceptible to surface contamination but should be monitored for emerging contaminants like PFAS.
How does Twisp's water compare to other cities?
Twisp ranks #13 out of 294 cities in Washington (better than 96% of state cities) and #823 out of 15744 cities nationally (95th percentile). The grade of A reflects the combined assessment of violation history, lead and copper levels, PFAS contamination, and regulatory compliance.
Does Twisp's small water system affect quality?
Twisp's system serves approximately 1,044 residents. Small community water systems (under 3,300 people) may have fewer financial resources for infrastructure upgrades and advanced treatment technologies. However, they are held to the same EPA drinking water standards as larger systems. This system has 42 violations on record.