EPA UCMR 5 Data · Idaho

PFAS Drinking-Water Monitoring Results in Idaho

This page summarizes EPA Fifth Unregulated Contaminant Monitoring Rule (UCMR 5, 2023–2025) drinking-water monitoring records linked to ZIP codes in Idaho, as processed for the PFAS Estimator national dataset. Data updated: July 2026.

9.8% of Idaho ZIP codes in this dataset (61 total)
had at least one regulated PFAS compound detected at or above its applicable EPA threshold (6 of 61 ZIP codes). Of those, 2 (33.3%) had more than one compound at or above threshold. This dataset includes only ZIP codes with at least one recorded PFAS detection; ZIP codes where all compounds returned non-detect are not represented.

Compounds detected in Idaho

Detection prevalence, exceedance, and concentration by compound, Idaho ZIP codes in the EPA UCMR 5 analytic dataset.
Compound Applicable threshold ZIP codes detected At/above threshold Mean detected Maximum detected
PFOA0.004 µg/L (MCL)1 (1.6% of state)1 (100.0%) — all detections at/above limit by construction0.0059 µg/L0.0059 µg/L
PFOS0.004 µg/L (MCL)5 (8.2% of state)5 (100.0%) — all detections at/above limit by construction0.0105 µg/L0.0282 µg/L
PFHxS0.01 µg/L (MCL)6 (9.8% of state)2 (33.3% of detected)0.0087 µg/L0.0254 µg/L
PFNA0.01 µg/L (MCL)2 (3.3% of state)1 (50.0% of detected)0.0296 µg/L0.051 µg/L
PFBS2.0 µg/L (HI reference)5 (8.2% of state)not calculated¹0.0048 µg/L0.0067 µg/L
Lithium7.36 µg/L (reference, not a regulatory limit)59 (96.7% of state)59 (100.0%) at/above reference44.6169 µg/L150.0 µg/L
PFPeA— (no federal limit)6 (9.8% of state)0.0056 µg/L0.008 µg/L

ZIP codes in this dataset (Idaho)

61 ZIP codes with at least one recorded PFAS detection. Click a ZIP code to view its full compound-level results.

Per-ZIP-code detection summary for Idaho
ZIP code Compounds detected At/above threshold
832011No
832021No
832031No
832041No
832051No
832061No
832091No
832111No
832211No
832742No
833011No
833031No
833161No
833181No
833361No
833381No
833401No
833501No
834011No
834021No
834031No
834041No
834051No
834061No
834401No
834421No
834451No
835013No
835301No
835391No
836051No
836071No
836161No
836171No
836341No
836423Yes (1)
836441No
836463Yes (1)
836483Yes (1)
836511No
836521No
836531No
836612No
836691No
836721No
836803Yes (1)
836861No
836871No
837021No
837031No
837047Yes (3)
837051No
837061No
837091No
837121No
837131No
837146Yes (2)
837161No
837251No
838551No
838581No

Methodology & limitations

Results are based on EPA UCMR 5 monitoring data (2023–2025), linked to ZIP codes via Public Water System Identifier. Non-detections are not present in this analytic dataset. For each compound and ZIP code, the highest observed concentration across the monitoring period is retained; this characterizes the upper bound of observed drinking-water concentrations, not a long-term average or an individual exposure estimate. A single water system may serve multiple ZIP codes, so the same monitoring record can appear for more than one ZIP in this table. ZIP-code assignment reflects water-system service area geography and does not establish individual household exposure. Private wells are not represented unless served by a monitored public water system. PFOA and PFOS are reported by detection prevalence because the UCMR 5 reporting limit equals their federal MCL. A full PFBS Hazard Index is not calculated because co-located, same-event multi-compound readings are not retained in this dataset. Lithium has no federal Maximum Contaminant Level; 7.36 µg/L is an evidence-based reference concentration from a prospective cohort study, not a regulatory threshold.

Related links

PFAS Estimator homepage & national ZIP lookup
Full national methodology, limitations, and dataset documentation
All states & territories index

Data from the EPA Unregulated Contaminant Monitoring Rule (UCMR 5), 2023–2025. Detection does not indicate a health risk. Not medical advice. Data updated: July 2026. · EPA Source