How many water violations are in Custer County?

Custer County has 1,289 total drinking water violations across 58 water systems, of which 133 are health-based violations. 89.7% of systems have at least one violation.

How many people get water from Custer County systems?

Water systems in Custer County serve approximately 5,848 people through 58 public water systems.

Has PFAS been detected in Custer County water?

No UCMR5 PFAS testing results are in this extract for Custer County water systems.

What types of water sources supply Custer County?

Water systems in Custer County use GW (57 systems), SW (1 systems) as their primary water sources.

Are health-based violations serious?

Health-based violations indicate that drinking water exceeded Maximum Contaminant Levels (MCLs) set by the EPA or failed treatment technique requirements. 10.3% of Custer County's violations are health-based. Among counties with any SDWIS violations, this extract puts Custer County in the lower health-based share band. Not all violations indicate immediate health risk, but they require corrective action.

Where does Custer County sit among U.S. counties for water-system population?

According to EPA SDWIS county population served used on /counties, Custer County ranks #2,712 of 3,254 counties by people served, and #38 of 44 counties in Idaho. Ordinals use the same total_population DESC sort as the counties directory. See /methodology#corpus-placement.

Counties → Idaho

Custer County, Idaho

Compiled by PlainWater · May 15, 2026

SDWIS compliance plate

Sheet ID037 · Custer County 58 sys · 1,289 viol · #2712/3254

VIOL-SEVERE · HEALTH-LOW · RANK-BOTTOM · PHOTO-FINISH · PFAS-NONE · SRC-GW · SYS-MID · BOOK-MOST

VIOL-SEVERE 89.7% flagged
HEALTH-LOW 10.3% health
RANK-BOTTOM #2712/3254
PHOTO-FINISH ±0.2 pp
PFAS-NONE No UCMR5 set
SRC-GW GW lead 98%
SYS-MID 58 systems
BOOK-MOST 6/7 fields

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

According to EPA SDWIS county population served used on /counties, Custer County ranks #2,712 of 3,254 counties by people served, and #38 of 44 counties in Idaho. See methodology · corpus placement.

Custer County standing, lower-flagged corpus third

Flagged-system rate 89.7% is at or below the corpus lower third (≤ 92.7% flagged) across 2,973 counties with ≥3 SDWIS systems . Health-based share 10.3% is health-based share at or below the lower third (≤ 10.3%) . No UCMR5 tests in this extract for Custer County . Population served ranks #2,712 of 3,254 · #38 of 44 in Idaho.

Water Systems

System Name	Population	Violations	PFAS
Challis City Of	900	191	-
Mackay City Of	566	41	-
Joe T Fallini (Blm)	540	17	-
Usfs Fishook Well	460	5	-
Usfs Glacier View Campground	314	3	-
Mountain Village Lodge and Restaurant	225	37	-
Sawtooth Luces	200	14	-
Thompson Creek Mine	190	31	-
Stanley Kasino Club	150	85	-
Leslie Lds Church	147	0	-
Round Valley Water Assn	125	84	-
Usfs Sunny Gulch Campground	122	5	-
North Gate Inn	100	45	-
7 C Junction	100	17	-
Challis Lds Church	97	4	-
Stanley High Country Inn	75	29	-
Blm Bay Horse Recreation Site	70	12	-
Idaho Rocky Mountain Ranch	65	4	-
Idfg Sawtooth Fish Hatchery	63	11	-
Usfs Stanley Lake Campground	56	2	-
Usfs Chinook Bay	54	3	-
Blm East Fork Recreation Site	50	13	-
Challis Hot Springs Campground	50	16	-
Stanley River Retreat and Cabins	50	18	-
Usfs Redfish Waste Disposal	50	13	-
Idpr Yankee Fork Historic Area	50	10	-
Blm Cottonwood Recreation Site	50	7	-
Usfs Stanley Office	49	28	-
Old Sawmill Station	45	34	-
Usfs Salmon River Campground	44	1	-
Living Waters Ranch	40	41	-
Usfs Bonanza Guard Station and Ycc Camp	40	3	-
Usfs Yankee Fork New Ranger Station	40	39	-
Stanley Community Library	40	22	-
White Knob RV Park	38	27	-
White Knob Motel and Pool	38	21	-
Usfs Mormon Bend Campground	31	3	-
Antelope Creek Living Center	27	24	-
Usfs Wildhorse Campground North Well	26	0	-
Stanley RV & Camp	26	41	-
Lower Stanley Country Store	25	13	-
Rod and Gun Club	25	60	-
Salmon River Emergency Clinic	25	64	-
Stanley Community Center	25	10	-
Stanley School	25	17	-
Torreys Burnt Creek Inn	25	19	-
Valley Creek Lodge	25	11	-
Usfs Lakeview Campground	25	16	-
Usfs Beaver Ck Campground	25	0	-
Usfs Lola Creek Campground East	25	5	-

Compare beyond Idaho

Lower-flagged peers for Custer County

Cross-state counties nearest Custer County on flagged-system share (89.7%) and cumulative violation count (1,289). 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

Compiled by PlainWater, Drinking Water Quality Editorial Process · May 15, 2026

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.