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Counties → Montana

Flathead County, Montana

SDWIS compliance plate

Sheet MT029 · Flathead County 324 sys · 20,270 viol · #546/3254

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

  • VIOL-SEVERE 93.5% flagged
  • HEALTH-LOW 11.4% health
  • RANK-TOP #546/3254
  • PHOTO-FINISH ±0.0 pp
  • PFAS-MID 33.3% detect
  • SRC-GW GW lead 98%
  • SYS-LARGE 324 systems
  • BOOK-FULL 7/7 fields

Nearest flagged-rate peer: Stillwater County (+ 0 pp flagged-rate)

According to EPA SDWIS county population served used on /counties, Flathead County ranks #546 of 3,254 counties by people served, and #4 of 56 counties in Montana. See methodology · corpus placement.

Flathead County standing, mid-flagged corpus third

Flagged-system rate 93.5% is in the corpus middle third (≤ 100.0% flagged) across 2,973 counties with ≥3 SDWIS systems . Health-based share 11.4% is health-based share in the middle third (≤ 24.5%) . UCMR5 detect rate 33.3% is UCMR5 detect rate in the tested-pool middle third (≤ 33.3%) . Population served ranks #546 of 3,254 · #4 of 56 in Montana.

Flagged-rate neighbourhood around Flathead County

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

0% 20% 40% 60% 80% 100% Powder River · lowest Park · near Flathead · this county Petroleum · highest 66.7% 93.1% 93.1% 93.3% 93.5% 93.5% 100%

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

Water Systems

System Name Population Violations PFAS
Kalispell Public Works 25,000 224 Detected
Whitefish City Of 10,418 102 Clean
Flathead County Water and Sewer 7,775 19 Clean
Bigfork County Water and Sewer 6,100 43 Clean
Columbia Falls City Of 4,450 99 Clean
Ridge Run 3,500 15 -
Glacier Park International Airport 2,680 31 -
Big Mountain Water Company 2,435 415 -
Lakeside Water System 1,225 16 -
Hungry Horse Co Water and Sewer District 1,135 108 -
Meadow Lake Co Water and Sewer District 950 112 -
Town Pump Columbia Falls 2 910 9 -
Glacier Bible Camp 903 11 -
Somers Co Water and Sewer Dist 765 26 -
Easthaven Baptist Church 700 10 -
West Valley School District No 1 650 17 -
Hope Church 650 32 -
Ptarmigan Village Inc 600 46 -
Glacier Raft Company 515 17 -
Big Sky Water Slide Col Falls 500 49 -
Headquarters Apgar 500 11 -
Lds Church Columbia Falls 500 8 -
Flathead Co Water District No 8 475 558 -
Coram County Water and Sewer District 450 46 -
Greenacres County Water and Sewer Dist 450 9 -
Country Estates Water Supply 430 112 -
Woodys Country Store 418 108 -
Blacktail Grocery 413 18 -
Meadow Manor 410 20 -
Lake McDonald Lodge 400 1 -
Forest Acres Tr Pk Whitefish 390 54 -
West Glacier KOA Campground 360 56 -
Cherry View 352 17 -
Stillwater Christian School 350 29 -
Martin City County Water District 340 18 -
Iron Horse Homeowners Assoc 335 63 -
Glacier View Golf Club 319 107 -
Ferndale Market Ferndale 310 59 -
Southside Public Water Supply 306 19 -
Majestic Valley Arena 306 10 -
Archer Acres 305 7 -
Mountain Villa Apts Kalispell 300 9 -
Snowline Acres 300 6 -
Northern Pines Community HOA 295 133 -
Smith Valley School Lower 280 16 -
Ap Williams 280 44 -
Ridgewood Terrace MHP 280 20 -
Rocky Mountain HI RV Park 275 87 -
Alpine Pacific Utilities 270 104 -
Glacier Ridge HOA & Water Association 262 40 -

Compare beyond Montana

Mid-flagged peers for Flathead County

Cross-state counties nearest Flathead County on flagged-system share (93.5%) and cumulative violation count (20,270). 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.