ZIP 58638 falls in Morton County, North Dakota. We have not measured septic data for this county yet. The county page below has what we do know: where records are kept and whether the portal is public.
ZCTA 58638 is not entirely inside one county. Land-area share is from the 2020 Census ZCTA-to-county relationship file.
| County | Land in this ZIP | Documents held | On septic (county) | On sewer (county) |
|---|---|---|---|---|
| Morton County, North Dakota | 43% | — | — | — |
| Mercer County, North Dakota | 30% | — | — | — |
| Stark County, North Dakota | 16% | — | — | — |
| Grant County, North Dakota | 7% | 3 | — | — |
| Dunn County, North Dakota | 4% | 7 | — | — |
Land-area overlap is from the 2020 Census Bureau ZCTA5-to-county relationship file, not an estimate of ours. Parcel and document counts are rows we hold, not a survey of every property in the ZIP. Last verified 2026-09-01.
We have not measured septic-versus-sewer status for this county yet.
ZIP 58638 spans 5 counties: Morton County, North Dakota, Mercer County, North Dakota, Stark County, North Dakota, Grant County, North Dakota, Dunn County, North Dakota.