Save town Compare Needs More Love
Town guide

Seneca

A township of 2,881 people in McHenry County, Illinois
Be the first to joinEarn karma for joining →
1

Now in Seneca

What’s happening this week

All posts →
From your neighbors

What’s happening

A preview of what neighbors share. Be the first to post in Seneca.

Weather

Forecast →
Coming up

Upcoming events

Nothing on the calendar yet

Put the next local happening — a market, a meeting, a concert — on the map.

Add an event →
Around town

Local news

All news →

Loading local headlines…

Headlines via Google News · Articles belong to their publishers.

2

Around town

The places and views that make it Seneca

Explore places →

Outdoors in Seneca

Parks & trails →
Map of Seneca: conserved land, trails and the top places to walk
Conserved land3.8%876 of 22,823 acres
Trails5.7 mi0.2 mi per sq mi
Parks & preserves4304 conserved acres per 1,000 residents

Trails & parks © OpenStreetMap contributors · Conserved land: USGS PAD-US

3

Know Seneca

The town at a glance, and the guide to how things work

Open the full guide →

About Seneca

Township in Illinois, United States
2,893Population
36 sq miArea

Seneca Township is located in McHenry County, Illinois. As of the 2020 census, its population was 2,893 and it contained 1,102 housing units. It includes the census-designated place of Franklinville.

Official town website ↗

From Wikipedia, licensed CC BY-SA 4.0 · facts via Wikidata (CC0)

Living in Seneca

Work & commute in Seneca

Full picture →

Most working residents leave Seneca for work: only 1% work in town. The top destinations are Chicago (12%), Huntley (6%) and Elgin (5%). Half commute less than 28 miles.

Chicago
12%
Huntley
6%
Elgin
5%
Woodstock
4%
Census LEHD 2023 · ACSWork & commute in Seneca →

Health in Seneca

B+

Health Grade B+

Healthier than 73% of U.S. towns on seven CDC estimates.

Compared with Illinois

4better than IL·1worse

of 32 measures CDC estimates. The other 27 are too close to call.

BetterToo close to callWorse

What stands out

Care nearby

Mercy Harvard HospitalHarvard · 10.2 mi · ER · rural critical access
Aunt Martha's Woodstock Community Health CenterWoodstock · 6.4 mi · sliding-scale fees
Primary careNo shortage
DentalNo shortage
Mental healthShortage · county-wide
CDC PLACES 2025 · modeled estimates for adults · ZIP codes 60098, 60152, 60180 · CMS · HRSAHealth in Seneca →

Natural hazards in Seneca

41
Moderate

Expected storm and flood damage is higher than in 41% of U.S. communities.

🌊 Inland flooding🌪️ Tornadoes🥶 Cold waves
FEMA National Risk Index December 2025 · OpenFEMANatural hazards in Seneca →

Climate in Seneca

Full climate →

Seneca has cold, snowy winters and pleasant summers. A typical July afternoon reaches 83°, a January night drops to 14°, and about 31 inches of snow falls in a normal winter.

32° / 17°Winter
58° / 37°Spring
82° / 60°Summer
61° / 41°Fall
NOAA U.S. Climate Normals, 1991–2020Climate in Seneca →

Schools in Seneca

All Seneca schools →
B+

School Grade B+

The public schools Seneca’s kids attend, from kindergarten through graduation, outperform 69% of Illinois’s districts on state tests and graduation. Among towns with similar incomes, they sit near the middle.

#71Best public schoolsof 384 in IL
DistrictMarengo CHSD 154Schools2

School data from the U.S. Department of Education (NCES, EDFacts). The School Grade is our own summary of state test results and graduation rates, graded within IL. Ratings are from neighbors.

Libraries near Seneca

See all →
Nearest: Woodstock Public LibraryWoodstock · 4.1 miles · 65 hrs a week
Famous people from SenecaWriters, athletes, leaders and more who were born in Seneca.Meet them →

How things work in Seneca

All explainers →
The door’s open

Where to, neighbor?

You’re in Seneca, ILMcHenry CountyView boundary

Nearby

All towns & citiesExplore the map
Loading boundary…

Seneca is your selected town. The feed includes posts assigned to this town, not a distance radius or ZIP code.

Neighborhoods narrow the feed further, while townwide announcements, events, and issues remain visible.

Boundary source: https://tigerweb.geo.census.gov/arcgis/rest/services/TIGERweb/Places_CouSub_ConCity_SubMCD/MapServer/15 · 2025-01-01