Keizer, City Of

PFAS monitoring results for a public water system in Oregon

OR4100744UCMR 5EPA monitoring data
<MRLHighest PFOA result, ppt
<MRLHighest PFOS result, ppt
0.39Highest Hazard Index
521Results
PWSID
OR4100744
State
Oregon
System type
community water system (CWS)
Population served
38,585
City
Keizer
Counties
Marion County
Primary source water
groundwater
UCMR 5 sampling
2024-06-18 to 2025-03-18 · 15 entry point(s) · water types: GW
Service-area boundary
authoritative

Hazard Index below its limit highest single result
Hazard Index below its limit worst entry-point average

These are monitoring results collected under EPA's Fifth Unregulated Contaminant Monitoring Rule (UCMR 5) at entry points, where treated water enters the distribution system; they are not tap-water samples. They are not compliance determinations: compliance with EPA's 2024 PFAS limits is judged on running annual averages of compliance monitoring, required from 2029, so a single UCMR 5 result at or above a limit is not a violation. “< MRL” means the compound was not quantified at EPA's minimum reporting level; it does not mean zero.

Compared with EPA's 2024 values

Highest single resultWorst entry-point average*Limit
PFOA (ppt)<MRL04
PFOS (ppt)<MRL04
Hazard Index0.390.391.0†

“<MRL” = every result for the compound was below its reporting limit. * Mean of all samples at each entry point with non-detects = 0 (EPA compliance convention; the Hazard Index also uses non-detects = 0); a screening comparison, not a formal running annual average. † Rescission proposed May 2026. PFOA/PFOS MCL 4 ppt (2024 NPDWR, in effect). PFHxS, PFNA, HFPO-DA (10 ppt each) and the Hazard Index (1.0) are 2024 NPDWR values; EPA proposed rescinding them on 18 May 2026 (comment period closed 20 Jul 2026).

No Oregon PFAS drinking-water standard in effect or proposed as of 2026-10-17: No Oregon-specific PFAS drinking-water standard; Oregon Health Authority implements the federal NPDWR (OHA PFAS Rule page).

Sampling history

Sampled 2024-06-18 to 2025-03-18 · 15 entry point(s) · water types: GW · 23 sampling visits. PFAS in ppt (ng/L).

DateEntry pointEventPFOAPFOSHIOther detections
2024-06-18Well #1 (Carlhaven West) (GW)SE1<4<40none
2024-06-18Well #10 (Chemawa) (GW)SE1<4<40none
2024-06-18Well #12 (17th Avenue) (GW)SE1<4<40none
2024-06-18Well #14 (Meadows) (GW)SE1<4<40none
2024-06-18Well #16 (Reitz) (GW)SE1<4<40none
2024-06-18Well #18 (Lacey Court) (GW)SE1<4<40none
2024-06-18Well #19 (City Hall) (GW)SE1<4<40none
2024-06-18Well #2 (Willamette Manor) (GW)SE1<4<40none
2024-06-18Well #4 (Keizer Station) (GW)SE1<4<40none
2024-06-18Well #5 (Cherry Avenue) (GW)SE1<4<40none
2024-06-18Well #7 (Wiessner) (GW)SE1<4<40.39none
2024-06-18Well #8 (Delta) (GW)SE1<4<40none
2024-06-18Well #9 (McNary) (GW)SE1<4<40none
2024-06-18Well#15 (Ridge Dr.) (GW)SE1<4<40none
2024-06-18Well#6 (Carlhaven East) (GW)SE1<4<40.35none
2024-12-30Well #1 (Carlhaven West) (GW)SE2n/an/an/anone
2024-12-30Well #12 (17th Avenue) (GW)SE2n/an/an/anone
2024-12-30Well #5 (Cherry Avenue) (GW)SE2n/an/an/anone
2024-12-30Well #9 (McNary) (GW)SE2n/an/an/anone
2024-12-30Well#15 (Ridge Dr.) (GW)SE2n/an/an/anone
2025-01-23Well #9 (McNary) (GW)SE2<4<40none
2025-01-23Well#6 (Carlhaven East) (GW)SE2<4<40.34none
2025-03-18Well #16 (Reitz) (GW)SE2n/an/an/anone

“<4” = not detected at the reporting limit shown; “n/a” = not analyzed in that sample. Highlighted = at or above the 4 ppt MCL. HI computed per sample with non-detects as 0. Other detections lists every other quantified compound (lithium in µg/L).

All results by entry point

521 results. Each column is one sampling visit (date and UCMR 5 sample event). A number is a measured concentration; “< 4” = below the minimum reporting level shown; “–” = not analyzed in that visit. PFAS in ppt (ng/L); lithium in µg/L.

Well #1 (Carlhaven West) facility 00001 · sample point 00001 · groundwater

CompoundMRL2024-06-18
SE1
2024-12-30
SE2
11Cl-PF3OUdS5 ppt< 5–
4:2 FTS3 ppt< 3–
6:2 FTS5 ppt< 5–
8:2 FTS5 ppt< 5–
9Cl-PF3ONS2 ppt< 2–
ADONA3 ppt< 3–
HFPO-DA5 ppt< 5–
NEtFOSAA5 ppt< 5–
NFDHA20 ppt< 20–
NMeFOSAA6 ppt< 6–
PFBA5 ppt< 5–
PFBS3 ppt< 3–
PFDA3 ppt< 3–
PFDoA3 ppt< 3–
PFEESA3 ppt< 3–
PFHpA3 ppt< 3–
PFHpS3 ppt< 3–
PFHxA3 ppt< 3–
PFHxS3 ppt< 3–
PFMBA3 ppt< 3–
PFMPA4 ppt< 4–
PFNA4 ppt< 4–
PFOA4 ppt< 4–
PFOS4 ppt< 4–
PFPeA3 ppt< 3–
PFPeS4 ppt< 4–
PFTA8 ppt< 8–
PFTrDA7 ppt< 7–
PFUnA2 ppt< 2–
lithium9 µg/L< 9< 9

Well #10 (Chemawa) facility 00004 · sample point 00004 · groundwater

CompoundMRL2024-06-18
SE1
11Cl-PF3OUdS5 ppt< 5
4:2 FTS3 ppt< 3
6:2 FTS5 ppt< 5
8:2 FTS5 ppt< 5
9Cl-PF3ONS2 ppt< 2
ADONA3 ppt< 3
HFPO-DA5 ppt< 5
NEtFOSAA5 ppt< 5
NFDHA20 ppt< 20
NMeFOSAA6 ppt< 6
PFBA5 ppt< 5
PFBS3 ppt< 3
PFDA3 ppt< 3
PFDoA3 ppt< 3
PFEESA3 ppt< 3
PFHpA3 ppt< 3
PFHpS3 ppt< 3
PFHxA3 ppt< 3
PFHxS3 ppt< 3
PFMBA3 ppt< 3
PFMPA4 ppt< 4
PFNA4 ppt< 4
PFOA4 ppt< 4
PFOS4 ppt< 4
PFPeA3 ppt< 3
PFPeS4 ppt< 4
PFTA8 ppt< 8
PFTrDA7 ppt< 7
PFUnA2 ppt< 2
lithium9 µg/L< 9

Well #12 (17th Avenue) facility 00013 · sample point 00013 · groundwater

CompoundMRL2024-06-18
SE1
2024-12-30
SE2
11Cl-PF3OUdS5 ppt< 5–
4:2 FTS3 ppt< 3–
6:2 FTS5 ppt< 5–
8:2 FTS5 ppt< 5–
9Cl-PF3ONS2 ppt< 2–
ADONA3 ppt< 3–
HFPO-DA5 ppt< 5–
NEtFOSAA5 ppt< 5< 5
NFDHA20 ppt< 20–
NMeFOSAA6 ppt< 6< 6
PFBA5 ppt< 5–
PFBS3 ppt< 3–
PFDA3 ppt< 3–
PFDoA3 ppt< 3–
PFEESA3 ppt< 3–
PFHpA3 ppt< 3–
PFHpS3 ppt< 3–
PFHxA3 ppt< 3–
PFHxS3 ppt< 3–
PFMBA3 ppt< 3–
PFMPA4 ppt< 4–
PFNA4 ppt< 4–
PFOA4 ppt< 4–
PFOS4 ppt< 4–
PFPeA3 ppt< 3–
PFPeS4 ppt< 4–
PFTA8 ppt< 8< 8
PFTrDA7 ppt< 7< 7
PFUnA2 ppt< 2–
lithium9 µg/L< 9–

Well #14 (Meadows) facility 00014 · sample point 00014 · groundwater

CompoundMRL2024-06-18
SE1
11Cl-PF3OUdS5 ppt< 5
4:2 FTS3 ppt< 3
6:2 FTS5 ppt< 5
8:2 FTS5 ppt< 5
9Cl-PF3ONS2 ppt< 2
ADONA3 ppt< 3
HFPO-DA5 ppt< 5
NEtFOSAA5 ppt< 5
NFDHA20 ppt< 20
NMeFOSAA6 ppt< 6
PFBA5 ppt< 5
PFBS3 ppt< 3
PFDA3 ppt< 3
PFDoA3 ppt< 3
PFEESA3 ppt< 3
PFHpA3 ppt< 3
PFHpS3 ppt< 3
PFHxA3 ppt< 3
PFHxS3 ppt< 3
PFMBA3 ppt< 3
PFMPA4 ppt< 4
PFNA4 ppt< 4
PFOA4 ppt< 4
PFOS4 ppt< 4
PFPeA3 ppt< 3
PFPeS4 ppt< 4
PFTA8 ppt< 8
PFTrDA7 ppt< 7
PFUnA2 ppt< 2
lithium9 µg/L< 9

Well #16 (Reitz) facility 90001 · sample point 90001 · groundwater

CompoundMRL2024-06-18
SE1
2025-03-18
SE2
11Cl-PF3OUdS5 ppt< 5–
4:2 FTS3 ppt< 3–
6:2 FTS5 ppt< 5–
8:2 FTS5 ppt< 5–
9Cl-PF3ONS2 ppt< 2–
ADONA3 ppt< 3–
HFPO-DA5 ppt< 5–
NEtFOSAA5 ppt< 5< 5
NFDHA20 ppt< 20–
NMeFOSAA6 ppt< 6< 6
PFBA5 ppt< 5–
PFBS3 ppt< 3–
PFDA3 ppt< 3–
PFDoA3 ppt< 3–
PFEESA3 ppt< 3–
PFHpA3 ppt< 3–
PFHpS3 ppt< 3–
PFHxA3 ppt< 3–
PFHxS3 ppt< 3–
PFMBA3 ppt< 3–
PFMPA4 ppt< 4–
PFNA4 ppt< 4–
PFOA4 ppt< 4–
PFOS4 ppt< 4–
PFPeA3 ppt< 3–
PFPeS4 ppt< 4–
PFTA8 ppt< 8< 8
PFTrDA7 ppt< 7< 7
PFUnA2 ppt< 2–
lithium9 µg/L< 9–

Well #18 (Lacey Court) facility 00018 · sample point 00018 · groundwater

CompoundMRL2024-06-18
SE1
11Cl-PF3OUdS5 ppt< 5
4:2 FTS3 ppt< 3
6:2 FTS5 ppt< 5
8:2 FTS5 ppt< 5
9Cl-PF3ONS2 ppt< 2
ADONA3 ppt< 3
HFPO-DA5 ppt< 5
NEtFOSAA5 ppt< 5
NFDHA20 ppt< 20
NMeFOSAA6 ppt< 6
PFBA5 ppt< 5
PFBS3 ppt< 3
PFDA3 ppt< 3
PFDoA3 ppt< 3
PFEESA3 ppt< 3
PFHpA3 ppt< 3
PFHpS3 ppt< 3
PFHxA3 ppt< 3
PFHxS3 ppt< 3
PFMBA3 ppt< 3
PFMPA4 ppt< 4
PFNA4 ppt< 4
PFOA4 ppt< 4
PFOS4 ppt< 4
PFPeA3 ppt< 3
PFPeS4 ppt< 4
PFTA8 ppt< 8
PFTrDA7 ppt< 7
PFUnA2 ppt< 2
lithium9 µg/L< 9

Well #19 (City Hall) facility 90003 · sample point 90003 · groundwater

CompoundMRL2024-06-18
SE1
11Cl-PF3OUdS5 ppt< 5
4:2 FTS3 ppt< 3
6:2 FTS5 ppt< 5
8:2 FTS5 ppt< 5
9Cl-PF3ONS2 ppt< 2
ADONA3 ppt< 3
HFPO-DA5 ppt< 5
NEtFOSAA5 ppt< 5
NFDHA20 ppt< 20
NMeFOSAA6 ppt< 6
PFBA5 ppt< 5
PFBS3 ppt< 3
PFDA3 ppt< 3
PFDoA3 ppt< 3
PFEESA3 ppt< 3
PFHpA3 ppt< 3
PFHpS3 ppt< 3
PFHxA3 ppt< 3
PFHxS3 ppt< 3
PFMBA3 ppt< 3
PFMPA4 ppt< 4
PFNA4 ppt< 4
PFOA4 ppt< 4
PFOS4 ppt< 4
PFPeA3 ppt< 3
PFPeS4 ppt< 4
PFTA8 ppt< 8
PFTrDA7 ppt< 7
PFUnA2 ppt< 2
lithium9 µg/L< 9

Well #2 (Willamette Manor) facility 00011 · sample point 00011 · groundwater

CompoundMRL2024-06-18
SE1
11Cl-PF3OUdS5 ppt< 5
4:2 FTS3 ppt< 3
6:2 FTS5 ppt< 5
8:2 FTS5 ppt< 5
9Cl-PF3ONS2 ppt< 2
ADONA3 ppt< 3
HFPO-DA5 ppt< 5
NEtFOSAA5 ppt< 5
NFDHA20 ppt< 20
NMeFOSAA6 ppt< 6
PFBA5 ppt< 5
PFBS3 ppt< 3
PFDA3 ppt< 3
PFDoA3 ppt< 3
PFEESA3 ppt< 3
PFHpA3 ppt< 3
PFHpS3 ppt< 3
PFHxA3 ppt< 3
PFHxS3 ppt< 3
PFMBA3 ppt< 3
PFMPA4 ppt< 4
PFNA4 ppt< 4
PFOA4 ppt< 4
PFOS4 ppt< 4
PFPeA3 ppt< 3
PFPeS4 ppt< 4
PFTA8 ppt< 8
PFTrDA7 ppt< 7
PFUnA2 ppt< 2
lithium9 µg/L< 9

Well #4 (Keizer Station) facility 90002 · sample point 90002 · groundwater

CompoundMRL2024-06-18
SE1
11Cl-PF3OUdS5 ppt< 5
4:2 FTS3 ppt< 3
6:2 FTS5 ppt< 5
8:2 FTS5 ppt< 5
9Cl-PF3ONS2 ppt< 2
ADONA3 ppt< 3
HFPO-DA5 ppt< 5
NEtFOSAA5 ppt< 5
NFDHA20 ppt< 20
NMeFOSAA6 ppt< 6
PFBA5 ppt< 5
PFBS3 ppt< 3
PFDA3 ppt< 3
PFDoA3 ppt< 3
PFEESA3 ppt< 3
PFHpA3 ppt< 3
PFHpS3 ppt< 3
PFHxA3 ppt< 3
PFHxS3 ppt< 3
PFMBA3 ppt< 3
PFMPA4 ppt< 4
PFNA4 ppt< 4
PFOA4 ppt< 4
PFOS4 ppt< 4
PFPeA3 ppt< 3
PFPeS4 ppt< 4
PFTA8 ppt< 8
PFTrDA7 ppt< 7
PFUnA2 ppt< 2
lithium9 µg/L< 9

Well #5 (Cherry Avenue) facility 00005 · sample point 00005 · groundwater

CompoundMRL2024-06-18
SE1
2024-12-30
SE2
11Cl-PF3OUdS5 ppt< 5–
4:2 FTS3 ppt< 3–
6:2 FTS5 ppt< 5–
8:2 FTS5 ppt< 5–
9Cl-PF3ONS2 ppt< 2–
ADONA3 ppt< 3–
HFPO-DA5 ppt< 5–
NEtFOSAA5 ppt< 5< 5
NFDHA20 ppt< 20–
NMeFOSAA6 ppt< 6< 6
PFBA5 ppt< 5–
PFBS3 ppt< 3–
PFDA3 ppt< 3–
PFDoA3 ppt< 3–
PFEESA3 ppt< 3–
PFHpA3 ppt< 3–
PFHpS3 ppt< 3–
PFHxA3 ppt< 3–
PFHxS3 ppt< 3–
PFMBA3 ppt< 3–
PFMPA4 ppt< 4–
PFNA4 ppt< 4–
PFOA4 ppt< 4–
PFOS4 ppt< 4–
PFPeA3 ppt< 3–
PFPeS4 ppt< 4–
PFTA8 ppt< 8< 8
PFTrDA7 ppt< 7< 7
PFUnA2 ppt< 2–
lithium9 µg/L< 9–

Well #7 (Wiessner) facility 00010 · sample point 00010 · groundwater

CompoundMRL2024-06-18
SE1
PFHxS3 ppt3.9
11Cl-PF3OUdS5 ppt< 5
4:2 FTS3 ppt< 3
6:2 FTS5 ppt< 5
8:2 FTS5 ppt< 5
9Cl-PF3ONS2 ppt< 2
ADONA3 ppt< 3
HFPO-DA5 ppt< 5
NEtFOSAA5 ppt< 5
NFDHA20 ppt< 20
NMeFOSAA6 ppt< 6
PFBA5 ppt< 5
PFBS3 ppt< 3
PFDA3 ppt< 3
PFDoA3 ppt< 3
PFEESA3 ppt< 3
PFHpA3 ppt< 3
PFHpS3 ppt< 3
PFHxA3 ppt< 3
PFMBA3 ppt< 3
PFMPA4 ppt< 4
PFNA4 ppt< 4
PFOA4 ppt< 4
PFOS4 ppt< 4
PFPeA3 ppt< 3
PFPeS4 ppt< 4
PFTA8 ppt< 8
PFTrDA7 ppt< 7
PFUnA2 ppt< 2
lithium9 µg/L< 9

Well #8 (Delta) facility 00006 · sample point 00006 · groundwater

CompoundMRL2024-06-18
SE1
11Cl-PF3OUdS5 ppt< 5
4:2 FTS3 ppt< 3
6:2 FTS5 ppt< 5
8:2 FTS5 ppt< 5
9Cl-PF3ONS2 ppt< 2
ADONA3 ppt< 3
HFPO-DA5 ppt< 5
NEtFOSAA5 ppt< 5
NFDHA20 ppt< 20
NMeFOSAA6 ppt< 6
PFBA5 ppt< 5
PFBS3 ppt< 3
PFDA3 ppt< 3
PFDoA3 ppt< 3
PFEESA3 ppt< 3
PFHpA3 ppt< 3
PFHpS3 ppt< 3
PFHxA3 ppt< 3
PFHxS3 ppt< 3
PFMBA3 ppt< 3
PFMPA4 ppt< 4
PFNA4 ppt< 4
PFOA4 ppt< 4
PFOS4 ppt< 4
PFPeA3 ppt< 3
PFPeS4 ppt< 4
PFTA8 ppt< 8
PFTrDA7 ppt< 7
PFUnA2 ppt< 2
lithium9 µg/L< 9

Well #9 (McNary) facility 00008 · sample point 00008 · groundwater

CompoundMRL2024-06-18
SE1
2024-12-30
SE2
2025-01-23
SE2
11Cl-PF3OUdS5 ppt< 5–< 5
4:2 FTS3 ppt< 3–< 3
6:2 FTS5 ppt< 5–< 5
8:2 FTS5 ppt< 5–< 5
9Cl-PF3ONS2 ppt< 2–< 2
ADONA3 ppt< 3–< 3
HFPO-DA5 ppt< 5–< 5
NEtFOSAA5 ppt< 5< 5–
NFDHA20 ppt< 20–< 20
NMeFOSAA6 ppt< 6< 6–
PFBA5 ppt< 5–< 5
PFBS3 ppt< 3–< 3
PFDA3 ppt< 3–< 3
PFDoA3 ppt< 3–< 3
PFEESA3 ppt< 3–< 3
PFHpA3 ppt< 3–< 3
PFHpS3 ppt< 3–< 3
PFHxA3 ppt< 3–< 3
PFHxS3 ppt< 3–< 3
PFMBA3 ppt< 3–< 3
PFMPA4 ppt< 4–< 4
PFNA4 ppt< 4–< 4
PFOA4 ppt< 4–< 4
PFOS4 ppt< 4–< 4
PFPeA3 ppt< 3–< 3
PFPeS4 ppt< 4–< 4
PFTA8 ppt< 8< 8–
PFTrDA7 ppt< 7< 7–
PFUnA2 ppt< 2–< 2
lithium9 µg/L< 9––

Well#15 (Ridge Dr.) facility 00015 · sample point 00015 · groundwater

CompoundMRL2024-06-18
SE1
2024-12-30
SE2
11Cl-PF3OUdS5 ppt< 5–
4:2 FTS3 ppt< 3–
6:2 FTS5 ppt< 5–
8:2 FTS5 ppt< 5–
9Cl-PF3ONS2 ppt< 2–
ADONA3 ppt< 3–
HFPO-DA5 ppt< 5–
NEtFOSAA5 ppt< 5< 5
NFDHA20 ppt< 20–
NMeFOSAA6 ppt< 6< 6
PFBA5 ppt< 5–
PFBS3 ppt< 3–
PFDA3 ppt< 3–
PFDoA3 ppt< 3–
PFEESA3 ppt< 3–
PFHpA3 ppt< 3–
PFHpS3 ppt< 3–
PFHxA3 ppt< 3–
PFHxS3 ppt< 3–
PFMBA3 ppt< 3–
PFMPA4 ppt< 4–
PFNA4 ppt< 4–
PFOA4 ppt< 4–
PFOS4 ppt< 4–
PFPeA3 ppt< 3–
PFPeS4 ppt< 4–
PFTA8 ppt< 8< 8
PFTrDA7 ppt< 7< 7
PFUnA2 ppt< 2–
lithium9 µg/L< 9–

Well#6 (Carlhaven East) facility 00016 · sample point 00016 · groundwater

CompoundMRL2024-06-18
SE1
2025-01-23
SE2
PFHxS3 ppt3.53.4
11Cl-PF3OUdS5 ppt< 5< 5
4:2 FTS3 ppt< 3< 3
6:2 FTS5 ppt< 5< 5
8:2 FTS5 ppt< 5< 5
9Cl-PF3ONS2 ppt< 2< 2
ADONA3 ppt< 3< 3
HFPO-DA5 ppt< 5< 5
NEtFOSAA5 ppt< 5–
NFDHA20 ppt< 20< 20
NMeFOSAA6 ppt< 6–
PFBA5 ppt< 5< 5
PFBS3 ppt< 3< 3
PFDA3 ppt< 3< 3
PFDoA3 ppt< 3< 3
PFEESA3 ppt< 3< 3
PFHpA3 ppt< 3< 3
PFHpS3 ppt< 3< 3
PFHxA3 ppt< 3< 3
PFMBA3 ppt< 3< 3
PFMPA4 ppt< 4< 4
PFNA4 ppt< 4< 4
PFOA4 ppt< 4< 4
PFOS4 ppt< 4< 4
PFPeA3 ppt< 3< 3
PFPeS4 ppt< 4< 4
PFTA8 ppt< 8–
PFTrDA7 ppt< 7–
PFUnA2 ppt< 2< 2
lithium9 µg/L< 9–

Statistics by compound

CompoundResultsDetectedHighest (date)Mean boundsKM medianP75P90P95
PFHxS1718%3.9
2024-06-18
0.64–3.11<MRL<MRL3.53.9

Never detected (29): 11Cl-PF3OUdS, 4:2 FTS, 6:2 FTS, 8:2 FTS, 9Cl-PF3ONS, ADONA, HFPO-DA, NEtFOSAA, NFDHA, NMeFOSAA, PFBA, PFBS, PFDA, PFDoA, PFEESA, PFHpA, PFHpS, PFHxA, PFMBA, PFMPA, PFNA, PFOA, PFOS, PFPeA, PFPeS, PFTA, PFTrDA, PFUnA, lithium.

Left-censored Kaplan–Meier statistics (Helsel 2005; Helsel & Lee 2006, NADA for R). Units: ppt; lithium µg/L. Each compound has one reporting limit, so the Kaplan–Meier mean equals the upper mean bound (non-detects at the MRL); the lower bound sets non-detects to 0. “<MRL” = the percentile falls below the reporting limit and cannot be estimated. These describe this system's UCMR 5 samples, not population estimates.

Sources

  • EPA UCMR 5 occurrence data text files (UCMR5_All.txt; samples 2023-01-09 to 2026-06-08; data summary dated Jul 2026)
  • EPA SDWIS via ECHO SDWA downloads, quarter 2026Q3
  • EPA Public Water System Service Areas v3 (Mar 2026)
  • US Census Bureau cartographic boundary counties 1:500k, 2024
  • EPA/USGS NHDPlus V2 (medium resolution) flowlines, Strahler order 2+

Data build 1e314dc9498d · 2026-10-18T04:06Z · UCMR 5 release Jul2026 · SDWIS 2026Q3. Data and methods.