County profile · EPA SDWIS + UCMR5
Fairfax County, Virginia
44 SDWIS-listed public water systems serve 1,317,489 people in Fairfax County. Violation rates use that full inventory; PFAS rates use only the UCMR5-tested subset.
- 44
- SDWIS water systems Larger third of counties
- 2,070
- Total violations Middle third of counties
- 93.2%
- SDWIS systems w/ a violation Middle third of counties
- 100.0%
- UCMR5 PFAS rate (6 tested) Upper third of counties with tests
SDWIS compliance plate
Sheet VA059 · Fairfax County 44 sys · 2,070 viol · #37/3254
VIOL-SEVERE · HEALTH-MID · RANK-TOP · PHOTO-FINISH · PFAS-HIGH · SRC-GW · SYS-MID · BOOK-FULL
- VIOL-SEVERE 93.2% flagged
- HEALTH-MID 20.1% health
- RANK-TOP #37/3254
- PHOTO-FINISH ±0.3 pp
- PFAS-HIGH 100.0% detect
- SRC-GW GW lead 84%
- SYS-MID 44 systems
- BOOK-FULL 7/7 fields
Nearest flagged-rate peer: Montgomery County ( -0.3 pp flagged-rate)
According to EPA SDWIS county population served used on /counties, Fairfax County ranks #37 of 3,254 counties by people served, and #1 of 95 counties in Virginia. See methodology · corpus placement.
Fairfax County standing, mid-flagged corpus third
Flagged-system rate 93.2% is in the corpus middle third (≤ 100.0% flagged) across 2,973 counties with ≥3 SDWIS systems . Health-based share 20.1% is health-based share in the middle third (≤ 24.5%) . UCMR5 detect rate 100.0% is UCMR5 detect rate above the tested-pool upper third (> 33.3%) . Population served ranks #37 of 3,254 · #1 of 95 in Virginia.
Flagged-rate neighbourhood around Fairfax County
Lowest/highest poles plus in-state counties nearest Fairfax County on % of SDWIS systems with ≥1 violation. Full ladder: /counties.
Water Systems
Compare beyond Virginia
Mid-flagged peers for Fairfax County
Cross-state counties nearest Fairfax County on flagged-system share (93.2%) and cumulative violation count (2,070). In-state neighbours stay on the compliance plate above.
Similar flagged-system rate
Nearest cross-state counties by % of SDWIS systems with at least one violation on record.
Similar violation load
Nearest cross-state counties by cumulative SDWIS violation count (all systems in the county).
Read our methodology · Check your water system - how this data is sourced, computed, and verified.
Every figure on PlainWater is rendered directly from EPA SDWIS drinking-water data, no number is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error.