Water quality report

CAPITOL WATER CORP

BOISE, ID · 9,000 people served · EPA PWSID ID4010022

The bottom line

CAPITOL WATER CORP (BOISE, ID), which serves about 9,000 people, has recorded 1 health-based drinking-water contaminant in EPA violation records since 2016, most notably Uranium. Its most recent lead 90th-percentile sample was 0.0 ppb, within the 15 ppb federal action level. EPA's UCMR5 program detected PFAS 'forever chemicals' in this system: PFNA (0.051 µg/L), PFOS (0.0098 µg/L), PFOA (0.0059 µg/L). PFOA/PFOS levels exceed the 2024 federal limit of 4 ppt (0.004 µg/L). A certified water filter can reduce these at the tap — see the certified options for each below.

health contaminants on record

PFAS detected (UCMR5)

total health violations since 2016

What the testing found

Measured levels from EPA violation records, compared to the federal limit (MCL). The black line marks the legal limit.

Copper

2.74× the federal limit

Measured 3560 ppb · federal limit 1300 ppb · latest 12/31/1998 · 0 violations since 2016

Short-term: nausea/vomiting/cramps; long-term: liver/kidney damage. Leaches from copper plumbing, worse with corrosive water.

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Uranium

1× the federal limit

Measured 31 µg/L · federal limit 30 µg/L · latest 01/01/2025 · 1 violation since 2016

Naturally occurring radioactive metal; MCL 30 ug/L. Kidney toxicity and cancer risk. Common in western groundwater.

Lead

Not detected

Measured 0 ppb · federal limit 15 ppb · latest 12/31/2023 · 0 violations since 2016

No safe level. Damages developing brain/nervous system in children; linked to lower IQ, kidney and cardiovascular harm in adults. Usually enters water from corroding pipes/solder, not the source.

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PFAS "forever chemicals"

Detected by EPA's UCMR5 monitoring. The 2024 federal limit for PFOA and PFOS is 4 ppt (0.004 µg/L).

PFNA

Detected

Measured 0.051 µg/L · sampled 12/6/2023 · detection limit 0.004 µg/L

PFOS

2.4× the 4 ppt limit

Measured 0.0098 µg/L · sampled 12/6/2023 · detection limit 0.004 µg/L

PFOA

1.5× the 4 ppt limit

Measured 0.0059 µg/L · sampled 8/8/2023 · detection limit 0.004 µg/L

PFHxS

Detected

Measured 0.0055 µg/L · sampled 8/8/2023 · detection limit 0.003 µg/L

PFPeA

Detected

Measured 0.0054 µg/L · sampled 12/6/2023 · detection limit 0.003 µg/L

PFHxA

Detected

Measured 0.0052 µg/L · sampled 12/6/2023 · detection limit 0.003 µg/L

PFBS

Detected

Measured 0.004 µg/L · sampled 8/8/2023 · detection limit 0.003 µg/L

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Your recommended fix

Filters certified to clean up your water

Your water shows Copper, PFOA, PFOS, PFAS. A refrigerator filter handles the most of this in one unit — these three are independently certified for the most of your contaminants (not marketing claims):

Best match for your water

ramco

P1WB2L

Covers 3 of your 4 filterable contaminants

REFRIGERATOR NSF certified

$27.79

13.9¢/gal

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EveryDrop by Whirlpool

EDR3RXD1B

Covers 3 of your 4 filterable contaminants

REFRIGERATOR NSF certified

$46.12

23.1¢/gal

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EveryDrop by Whirlpool

EDR3RXD1R

Covers 3 of your 4 filterable contaminants

REFRIGERATOR NSF certified

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Compare all certified refrigerator filters →

Want certainty about your tap specifically (not just the system)? A certified mail-in lab test is the gold standard — system-wide records can differ from your home's plumbing. Some links above are affiliate links — see our disclosure.

Sources & method. Contaminant levels and violations come from EPA's Safe Drinking Water Information System (health-based violations, 2016–present); PFAS from EPA UCMR5 monitoring (2023–2025). Levels shown are the highest recorded value in the violation records; a violation means the contaminant exceeded its federal limit at the system level. Your home's water can differ from the system average. Public domain data; we are not affiliated with the EPA.