Clark County, Washington has about 527,269 residents (Census 2024 estimate) and 25 community water systems in EPA records. The largest local system is Vancouver City of, serving about 373,047 people from groundwater.
✓ 0 of 6 largest systems with health-based violationsPFAS detected at 4 of 6 sampled systemsHardness 55–130 mg/L, varies by area
Public-record figures, not a test of your tap. Not 100% accurate or guaranteed. Confirm with a water test, your utility or a qualified pro before you buy or act.
How hard is Clark County water?
Vancouver City ofMeasured (utility report, 2025) · High confidence
55–130 mg/L(varies by area; no single average published)
Public-record figures, not a test of your tap. Not 100% accurate or guaranteed. Confirm with a water test, your utility or a qualified pro before you buy or act.
At this hardness most homes don't need a softener. Confirm with a test strip if you see scale.
Largest water systems in Clark County
The 6 biggest of 25 community water systems on EPA records for this county. Service areas don't follow county lines; your water bill names your provider.
Vancouver City of
WA5391200 · serves about 373,047 people · Groundwater
✓ No health-based violations✓ Lead below action levelPFAS detected (7 types)
Lead 90th percentile: 2.2 ppb (period starting 2021-01-01) Older result. Action level: 15 ppb (drops to 10 ppb on Nov 1, 2027).
PFOS: highest sample 18.6 ppt (16 of 20 samples); federal limit 4.0 ppt as a running annual average
PFOA: highest sample 11.5 ppt (10 of 20 samples); federal limit 4.0 ppt as a running annual average
PFBS: highest sample 7.6 ppt (14 of 20 samples); no individual limit; counted in EPA's PFAS mixture (hazard index) limit
PFPeA: highest sample 7.4 ppt (8 of 20 samples); no federal limit
PFHxA: highest sample 7.3 ppt (8 of 20 samples); no federal limit
PFHxS: highest sample 6.6 ppt (16 of 20 samples); federal limit 10.0 ppt as a running annual average, also counted in EPA's PFAS mixture (hazard index) limit (currently in effect; EPA has proposed removing it)
PFHpA: highest sample 3 ppt (1 of 20 samples); no federal limit
WA5313333 · serves about 153,526 people · Groundwater
✓ No health-based violations✓ Lead below action levelPFAS detected (5 types)
Lead 90th percentile: 1.8 ppb (period starting 2023-01-01) Older result. Action level: 15 ppb (drops to 10 ppb on Nov 1, 2027).
PFOS: highest sample 8.4 ppt (1 of 20 samples); federal limit 4.0 ppt as a running annual average
PFOA: highest sample 8 ppt (1 of 20 samples); federal limit 4.0 ppt as a running annual average
PFHxS: highest sample 5.3 ppt (1 of 20 samples); federal limit 10.0 ppt as a running annual average, also counted in EPA's PFAS mixture (hazard index) limit (currently in effect; EPA has proposed removing it)
PFBS: highest sample 4.1 ppt (1 of 20 samples); no individual limit; counted in EPA's PFAS mixture (hazard index) limit
PFHxA: highest sample 3.3 ppt (1 of 20 samples); no federal limit
Public-record figures, not a test of your tap. Not 100% accurate or guaranteed. Confirm with a water test, your utility or a qualified pro before you buy or act.
A PFAS detection is not a violation. Federal limits (4 ppt for PFOA and PFOS) apply to running annual averages, with compliance required by 2029. In May 2026 EPA proposed extending the PFOA/PFOS deadline to 2031 and removing other PFAS limits; not final as of 2026-10-21.
Test your own tap
These are public records for whole systems. Your home's pipes, fixtures and any private well can change what you drink. A certified lab test or a hardness test strip gives you your own numbers. Then use our PFAS and lead filter selector to see which certifications to look for.
Common questions about Clark County water
Is tap water in Clark County safe to drink?
None of the 6 largest systems here have a health-based violation in EPA records since October 2021. Vancouver City of's most recent lead 90th percentile was 2.2 ppb (2021), below the 15 ppb action level. Public records can't guarantee what comes out of your tap, especially with older plumbing, so a home test is the surest check.
How hard is the water in Clark County?
Vancouver City of reports hardness from 55 to 130 mg/L depending on where you live, with no single system-wide average, so check your area in its report or test your water.
Is there PFAS in Clark County water?
4 of the 6 sampled systems listed here detected at least one PFAS in EPA's UCMR 5 testing, and 7 results were above the level of a federal limit in at least one sample. A detection isn't a violation: federal PFAS limits apply to running annual averages starting in 2029.
Which water system serves my address in Clark County?
Most homes are served by Vancouver City of or one of the other systems listed on this page, but service areas don't follow county lines. Your water bill names your provider, and its annual Consumer Confidence Report has the full test results.
Data as of October 21, 2026. Figures are copied from public records and combined with our own calculations; they can be out of date or wrong. Tapped Out isn't affiliated with any utility or the EPA. Written and reviewed by the Tapped Out team. How we calculate · All sources.