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Tap water quality report

Caldwell, ID

EPA monitoring detected 18 contaminants across the 22 water suppliers serving Caldwell. A detection doesn't automatically mean the water is unsafe — see the highest level found for each below, with its EPA source and period.

22
water suppliers
77,637
people served
18
contaminants found
Idaho rankings Lead in Idaho PFAS in Idaho

What was found in Caldwell's water

The highest level seen across the city's suppliers, the EPA limit for each, and where the figure comes from.

ContaminantLevel vs EPA limitSuppliersSource
Nitrate
15200 µg/L 152%
of the EPA limit, in the worst sample — 10000 µg/L
 21/22 SYR4
Nitrate-Nitrite
14300 µg/L 143%
of the EPA limit, in the worst sample — 10000 µg/L
 16/22 SYR4
Fluoride
1050 µg/L 26%
of the EPA limit 4000 µg/L
 19/22 SYR4
Barium
170 µg/L 8.5%
of the EPA limit 2000 µg/L
 13/22 SYR4
Toluene
41.8 µg/L 4.2%
of the EPA limit 1000 µg/L
 2/22 SYR4
Combined Uranium
34 µg/L 113%
of the EPA limit, in the worst sample — 30 µg/L
 19/22 SYR4
Arsenic
26 µg/L 260%
of the EPA limit, in the worst sample — 10 µg/L
 20/22 SYR4
TTHM
16.3 µg/L 20%
of the EPA limit 80 µg/L
 2/22 SYR4
Lithium
16 µg/L
No EPA limit set
 1/22 UCMR-5
Gross Alpha, Excl. Radon And U
13.1 pCi/L 87%
of the EPA limit 15 pCi/L
 9/22 SYR4
Chromium
8 µg/L 8%
of the EPA limit 100 µg/L
 9/22 SYR4
Gross Beta Particle Activity
7.8 pCi/L
No EPA limit set
 2/22 SYR4
Total Haloacetic Acids (HAA5)
6.7 µg/L 11%
of the EPA limit 60 µg/L
 3/22 SYR4
Tetrachloroethylene
2.24 µg/L 45%
of the EPA limit 5 µg/L
 1/22 SYR4
Selenium
2 µg/L 4%
of the EPA limit 50 µg/L
 1/22 SYR4
Combined Radium (-226 And -228)
1.8 pCi/L 36%
of the EPA limit 5 pCi/L
 7/22 SYR4
Di(2-ethylhexyl) Phthalate
1.04 µg/L 17%
of the EPA limit 6 µg/L
 2/22 SYR4
Lead
0.0090 mg/L 60%
of the EPA limit 0.0150 mg/L
 22/22 LCR
Each bar shows the measured level as a share of the EPA limit: green is well under, amber is close to it, red is over. For lead and copper the limit applies to exactly the 90th-percentile figure shown, so red there means a real exceedance. For everything else the limit applies to a running annual average while the figure is the single worst sample on record — over 100% is worth reading, but is not by itself a violation. Formal violations are listed separately. These are the utilities' own EPA-reported results, not a city-wide average. A detection means the lab measured the substance — it isn't the same as exceeding a legal limit. Hover a source tag to see the EPA program and years behind each figure.

Water suppliers serving Caldwell

SupplierPopulation served
CALDWELL CITY OF 74,000
CALDWELL HOUSING AUTHORITY 1,100
EL RANCHO HEIGHTS 300
WOODVIEW ACRES PROPERTY OWNERS 245
KARCHER RANCHETTE WATER CORP 213
SOMERSET WEST WATER CORP 203
OWYHEE VILLAGE SUBD WATER ASSN INC 200
DRAKE SUBD 150
RIO VISTA WATER COMPANY 3 140
PAR ESTATES HOMEOWNERS ASSN 140
GEM STATE ACADEMY 121
COUNTRY CLUB SUBDIVISIONS WATER ASSN 120
PLEASANT VIEW MANOR 100
IDAHO YOUTH RANCH HANDS OF PROMISE 95
EAST LIZARD BUTTE WATER CORP 95
MAVERICK SUBD LASHER CONSTRUCTION 90
STECHER WATER USERS ASSN 70
STECHER MUTUAL WATER COMPANY 62
RICH SUBD 60
VANAL HEIGHTS WELL ASSN 48
VANAL HEIGHTS SWEET WATER 45
WILDROSE ESTATES 40

Frequently asked questions about Caldwell tap water

Is Caldwell tap water safe to drink?

EPA testing detected 18 contaminants in the water serving Caldwell. A detection isn't the same as a violation — most detected levels are within federal limits. Check the level and source for each contaminant above, and your utility's annual Consumer Confidence Report for the official compliance status.

How many water suppliers serve Caldwell?

22 public water suppliers report drinking-water monitoring for Caldwell, Idaho to the EPA. Each is listed above with its population served.

What contaminants are in Caldwell's water?

The contaminants EPA monitoring detected in Caldwell include Nitrate, Nitrate-Nitrite, Fluoride, Barium, Toluene. The full list, with the highest level found and the data source, is in the table above.

Where does this data come from?

Every figure is official EPA drinking-water monitoring — the Lead & Copper Rule, the UCMR-5 nationwide testing program, and the EPA Six-Year Review — not our own testing. Each number is labelled with its source and period.