Nemaha County is a county in Kansas, United States, in the northeastern corner of the state along the Nebraska line. It had a population of 10,273 at the 2020 census and covers 719 square miles (1,860 km2), of which 717 square miles are land, centred near 39°55′N 96°14′W.
Seneca is the county seat, and its postal code is 66538. The county has eight incorporated cities, three census-designated places, and several unincorporated communities; it observes Central time.
Towns & Villages in Nemaha County
Nemaha County has eight incorporated cities — led by Sabetha, the county’s largest community, and Seneca, the county seat — plus three census-designated places (CDPs) and a scatter of unincorporated communities and rural place names. The table below carries over every legitimate settlement from the county’s older place list; a handful of duplicate entries in that list have been merged.
| Place | Type | Pop. | ZIP |
|---|---|---|---|
| Seneca | City · seat | 2,139 | 66538 |
| Sabetha | City | 2,545 | 66534 |
| Centralia | City | 485 | 66415 |
| Bern | City | — | 66408 |
| Corning | City | — | 66417 |
| Goff | City | — | 66428 |
| Oneida | City | — | 66522 |
| Wetmore | City | — | 66550 |
| Baileyville | CDP | — | 66508 |
| Kelly | CDP | — | — |
| St. Benedict | CDP | — | — |
| America City | Unincorp. | — | — |
| Bancroft | Unincorp. | — | — |
| Berwick | Unincorp. | — | — |
| Capioma | Unincorp. | — | — |
| Granada | Unincorp. | — | — |
| Neuchatel | Unincorp. | — | — |
| Ontario | Unincorp. | — | — |
| Woodlawn | Unincorp. | — | — |
Two entries on the old page — “Cowpoke MH Park” and “Seneca MH Park” — are manufactured-home parks rather than separate places and are folded into Seneca above; a duplicated Kelly and a duplicated St. Benedict line have been merged into one row each.
ZIP Codes
- 66538 — Seneca (also serves St. Benedict and Seneca Township)
- 66534 — Sabetha
- 66415 — Centralia
- 66408 — Bern
- 66417 — Corning
- 66428 — Goff
- 66522 — Oneida
- 66550 — Wetmore
- 66508 — Baileyville
Smaller unincorporated communities such as Bancroft, Berwick, Capioma, Granada, Neuchatel, Ontario and Woodlawn share mail service with the nearest listed post-office town rather than carrying a ZIP of their own.
Geography
Nemaha County sits in the Glaciated Region of northeastern Kansas, a gently rolling landscape of loess-covered till plains cut by the Nemaha River and its tributaries, including the Black Vermillion and South Fork Nemaha. Farmland dominates the county, with wooded stream corridors along the major drainages. The county covers 719 square miles, of which about 2 square miles are water.
Nemaha County borders Richardson County, Nebraska to the northeast, Brown County, Kansas to the east, Jackson County, Kansas to the southeast, Pottawatomie County, Kansas to the southwest, Marshall County, Kansas to the west, and Pawnee County, Nebraska to the northwest.
Demographics
The 2020 census counted 10,273 residents, giving a density of about 14 people per square mile. Sabetha, at 2,545 residents, is the county’s largest community, followed by the county seat, Seneca, at 2,139. Nemaha County is heavily White (94.4%) with small Hispanic (2.6%), Black (0.6%) and Asian (0.4%) populations. Household income in the county runs close to the Kansas median of $70,333, reflecting a farm- and small-manufacturing-based economy rather than the higher incomes of the Kansas City or Wichita metro counties.
Economy & Local Life
Agriculture — corn, soybeans and cattle — anchors the county’s economy, alongside grain handling and farm-service businesses in Seneca and Sabetha. Sabetha is home to Morrill & Janes Health Center and several manufacturers that have long supplied the wider region, while Seneca serves as the county’s government and retail center. Nemaha Valley Community Hospital in Seneca and USD 285 (Cedar Vale) and USD 113 (Prairie Hills) school districts serve county residents.
History
Nemaha County was organized in 1855 and takes its name from the Nemaha River, itself derived from an Otoe-Missouria word. On May 30, 1879, an F4 tornado — remembered locally as the Irving tornado — cut an unusually wide, roughly 100-mile damage path through the county and neighboring counties, one of the most destructive twisters recorded in 19th-century Kansas. The county has voted Republican in nearly every presidential election since statehood, with Lyndon Johnson’s 1964 landslide the lone Democratic exception since 1936.
Getting There
U.S. Route 36 crosses the county east-west through Seneca, and U.S. Route 75 runs north-south along the county’s eastern side through Sabetha. Kansas highways fill out the local network.
- Topeka, Kansas — 55 miles south
- Lincoln, Nebraska — 80 miles north
- St. Joseph, Missouri — 60 miles southeast
- Manhattan, Kansas — 45 miles southwest
The nearest commercial airport is Manhattan Regional Airport (MHK); Kansas City International (MCI) offers wider connections about two hours southeast.
Frequently Asked Questions
Where is Nemaha County?
It is in northeastern Kansas, on the Nebraska border, between Topeka and the Nebraska line.
What is the population of Nemaha County?
It had a population of 10,273 at the 2020 census.
How big is Nemaha County?
It covers 719 square miles (1,860 km2), of which 717 square miles are land.
What is the Nemaha County seat?
Seneca is the county seat.
How many towns are in Nemaha County?
Eight incorporated cities, three census-designated places, and a number of smaller unincorporated communities.
What ZIP codes are in Nemaha County?
Nine post offices serve the county, including 66538 (Seneca), 66534 (Sabetha) and 66415 (Centralia).
What is the largest city in Nemaha County?
Sabetha, with 2,545 residents at the 2020 census, is larger than the county seat, Seneca.
More counties in this state: Towns and villages in Kansas.