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Counties → California

Monterey County, California

SDWIS compliance plate

Sheet CA053 · Monterey County 315 sys · 13,641 viol · #149/3254

VIOL-SEVERE · HEALTH-HIGH · RANK-TOP · PHOTO-FINISH · PFAS-LOW · SRC-GW · SYS-LARGE · BOOK-FULL

  • VIOL-SEVERE 95.9% flagged
  • HEALTH-HIGH 50.0% health
  • RANK-TOP #149/3254
  • PHOTO-FINISH ±0.2 pp
  • PFAS-LOW 6.3% detect
  • SRC-GW GW lead 90%
  • SYS-LARGE 315 systems
  • BOOK-FULL 7/7 fields

Nearest flagged-rate peer: Mono County ( -0.2 pp flagged-rate)

According to EPA SDWIS county population served used on /counties, Monterey County ranks #149 of 3,254 counties by people served, and #19 of 58 counties in California. See methodology · corpus placement.

Monterey County standing, mid-flagged corpus third

Flagged-system rate 95.9% is in the corpus middle third (≤ 100.0% flagged) across 2,973 counties with ≥3 SDWIS systems . Health-based share 50.0% is health-based share above the upper third (> 24.5%) . UCMR5 detect rate 6.3% is UCMR5 detect rate in the tested-pool middle third (≤ 33.3%) . Population served ranks #149 of 3,254 · #19 of 58 in California.

Flagged-rate neighbourhood around Monterey County

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

0% 20% 40% 60% 80% 100% Alpine · lowest Mono · near San Mateo · near Sutter · highest 70% 94.9% 95.7% 95.9% 96.2% 96.2% 97.1%

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

Water Systems

System Name Population Violations PFAS
Cwsc Salinas 123,679 24 Clean
Cal Am Water Company - Monterey 92,450 17 Detected
Alco Water Service 56,253 15 Clean
Marina Coast Water District 38,377 8 Clean
Soledad, City Of 19,455 22 Clean
Greenfield, City Of 18,967 13 Clean
Cwsc King City 16,334 4 Clean
Gonzales, City Of 8,327 24 Clean
Castroville Community Services District 7,515 13 Clean
Psmcsd - Pajaro 6,500 5 Clean
Soledad Mission WS 6,000 70 -
Cwsc Salinas Hills 5,293 6 Clean
Correctional Training Facility - Soledad 4,269 32 Clean
Cwsc Oak Hills 3,161 9 Clean
Salinas Valley State Prison 2,930 8 Clean
Seaside Municipal Water System 2,800 15 -
Fort Hunter Liggett 2,753 11 -
Caltrans Camp Roberts Rsra Sb 2,560 31 -
Little Bear Water Company 2,327 18 -
Cwsc las Lomas 2,084 5 Clean
Prunetree Shopping Center WS 2,000 28 -
Tasco Spreckels Water Company 1,772 14 -
Caltrans Camp Roberts Rsra Nb 1,750 38 -
Prunedale Shopping Center WS 1,650 34 -
Laguna Seca Recreation WS 1,248 198 -
Cal Am Water Company - Chualar 1,139 4 -
Cal Am Water Company - Hidden Hills 1,106 0 -
Cal Am Water Company - Toro 1,065 31 -
Csp-Andrew Molera State Reserve 1,005 8 -
San Antonio Lake Park North WS 1,002 27 -
Cal Am Water Company - Ambler Park 980 5 -
Santa Lucia Preserve WS 966 33 -
Psmcsd - Normco 928 25 -
Bud Antle, LLC-Soledad Facility WS 900 32 -
Psmcsd - Sunny Mesa 880 19 -
Csp-J.p. Burns Park 802 4 -
Corral de Tierra Country Club WS 705 41 -
Elkhorn School WS 694 16 -
El Camino Real WS #16 679 18 -
Prunedale School WS 655 31 -
San Antonio Lake Park South WS 653 50 -
Cdfw Elkhorn Slough Ecological Reserve 650 20 -
Nepenthe WS 618 38 -
Csp-Pfeiffer Big Sur 585 14 -
Carmel Riviera MWC 584 58 -
Echo Valley School WS 579 81 -
San Ardo WD 575 27 -
Monterey Mushrooms - Maher Crt 554 61 -
Gabilan WC 535 52 -
Psmcsd - Moss Landing Harbor WS 520 8 -

Compare beyond California

Mid-flagged peers for Monterey County

Cross-state counties nearest Monterey County on flagged-system share (95.9%) and cumulative violation count (13,641). 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

Read our methodology · Check your water system - how this data is sourced, computed, and verified.

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.