PlainWater

San Francisco County, California

SDWIS compliance plate

Sheet CA075 · San Francisco County 8 sys · 77 viol · #53/3254

VIOL-SEVERE · HEALTH-HIGH · RANK-TOP · PHOTO-FINISH · PFAS-MID · SRC-SW · SYS-TINY · BOOK-FULL

  • VIOL-SEVERE 87.5% flagged
  • HEALTH-HIGH 64.9% health
  • RANK-TOP #53/3254
  • PHOTO-FINISH ±0.1 pp
  • PFAS-MID 25.0% detect
  • SRC-SW SW lead 100%
  • SYS-TINY 8 systems
  • BOOK-FULL 7/7 fields

Nearest flagged-rate peer: Tehama County ( -0.1 pp flagged-rate)

According to EPA SDWIS county population served used on /counties, San Francisco County ranks #53 of 3,254 counties by people served, and #10 of 58 counties in California. See methodology · corpus placement.

San Francisco County standing, lower-flagged corpus third

Flagged-system rate 87.5% is at or below the corpus lower third (≤ 92.7% flagged) across 2,973 counties with ≥3 SDWIS systems . Health-based share 64.9% is health-based share above the upper third (> 24.5%) . UCMR5 detect rate 25.0% is UCMR5 detect rate in the tested-pool middle third (≤ 33.3%) . Population served ranks #53 of 3,254 · #10 of 58 in California.

Flagged-rate neighbourhood around San Francisco County

Lowest/highest poles plus in-state counties nearest San Francisco County on % of SDWIS systems with ≥1 violation. Full ladder: /counties.

0% 20% 40% 60% 80% 100% Alpine · lowest San Francisco · this county Sutter · highest 70% 87.4% 87.4% 87.5% 88% 88.1% 97.1%

Source: EPA SDWIS (county aggregates) As of 2026-05-15

Water Systems

Compare beyond California

Lower-flagged peers for San Francisco County

Cross-state counties nearest San Francisco County on flagged-system share (87.5%) and cumulative violation count (77). 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.

4 peers

Similar violation load

Nearest cross-state counties by cumulative SDWIS violation count (all systems in the county).

4 peers
Data sourced from EPA SDWIS and UCMR5 PFAS monitoring data. See our methodology for details. Retrieved and formatted by PlainWater

Every figure on PlainWater is rendered directly from EPA SDWIS drinking-water data, no number is typed in by an editor. This page draws directly on EPA SDWIS data, no figure is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error.