Swansea, Illinois
17 topographic sheets cover this place, the earliest surveyed in 1907 and the latest in 1991. It stands in St. Clair Township. It lies in ZIP code area 62226. It stands on Wolf Branch. The Survey maps it on the O'Fallon quadrangle. 14,386 people lived here at the 2020 count.
Population over time
2 figuresSwansea grew from 13,430 to 14,386 between 2010 and 2020. These are the recorded population figures Wikidata holds for this place, reached through the Geographic Names Information System number this page is keyed on rather than by name, so they belong to this place and not to another of the same name. Most are census counts, but not all are: an early figure may be a founding or settlement estimate, and an estimate published within five years of a census is left out. The change column is computed, and is left blank where more than 20 years separate a figure from the one before it, because a gap that long is not a change between two counts.
| Year | People | Change |
|---|---|---|
| 2010 | 13,430 | |
| 2020 | 14,386 | +956 (+7%) |
Topographic sheets covering this place
7 surveys from 17 printed sheetsMatched by testing this settlement's coordinate against the published boundary of every sheet in the United States Geological Survey's historical collection. Each opens the scanned sheet at the Survey.
- 1907 USGS Belleville quadrangle1:62500, 3 printings
- 1937 USGS O'Fallon quadrangle1:24000, 2 printings
- 1954 USGS O'Fallon quadrangle1:24000, 4 printings
- 1958 USGS Belleville quadrangle1:250000, 3 printings
- 1962 USGS Belleville quadrangle1:250000
- 1985 USGS Carlyle Lake quadrangle1:100000, 2 printings
- 1991 USGS O'Fallon quadrangle1:24000, 2 printings
Fires near this place
5 since 2008Regional context, not property-specific evidence. The federal wildfire occurrence database lists 5 fires within 5 miles of Swansea between 2008 and 2012, burning about 4 acres in total. None started naturally. None was recorded as arson. Distance is straight-line from the map coordinates, so a fire counted here may appear on a neighbouring settlement's page as well.
| Reported cause | Fires |
|---|---|
| Missing data/not specified/undetermined | 4 |
| Debris and open burning | 1 |
The most recent of them, most recent first, with the day each was reported and the service that recorded it.
| Date | Cause | Size | Reported by | Name on the report |
|---|---|---|---|---|
| 20 April 2008 | Debris and open burning | 1.0 acres | Illinois Division of Forestry Resources | WINSLOW |
| 13 April 2010 | Missing data/not specified/undetermined | 1.0 acres | Illinois Division of Forestry Resources | BELVDER |
| 7 March 2009 | Missing data/not specified/undetermined | 1.0 acres | Illinois Division of Forestry Resources | WINSLOW |
| 7 March 2009 | Missing data/not specified/undetermined | 1.0 acres | Illinois Division of Forestry Resources | CASEYVILLE |
| 30 November 2012 | Missing data/not specified/undetermined | under an acre | Illinois Division of Forestry Resources | ST CLAIR1 |
Settlements close enough to share some of these fires:
Mines and quarries near this place
6 within 5 milesRegional context, not property-specific evidence. The federal mineral resources record lists 6 workings within 5 miles of Swansea: 5 past producers, 1 prospect. None of them still produces. What was taken out: Clay, Stone, Crushed/Broken, Sand and Gravel, Construction. Distance is straight-line from the map coordinates, so a quarry counted here may appear on a neighbouring settlement's page as well.
| Where | Site | Commodity | Status | Recorded |
|---|---|---|---|---|
| St. Clair County Highway Department | Sand and Gravel, Construction | Past Producer | ||
| Belleville City Quarry | Stone, Crushed/Broken | Past Producer | ||
| Quality Stone Quarry and Mill No. 1 | Stone, Crushed/Broken | Past Producer | ||
| Hill Brick Co. Shale Pit | Clay | Past Producer | ||
| Hydraulic-Press Brick Co.Clay Pit 2 | Clay | Past Producer | ||
| Little Canteen Shale Exposure | Clay | Prospect |
Storms near this place
16 since 1995Regional context, not property-specific evidence. The National Weather Service names Swansea in 16 storm reports between 1995 and 2025: 12 thunderstorm wind, 4 hail. No death or injury is recorded in these reports. Each account below is quoted exactly as the forecast office filed it, from the NOAA Storm Events Database, and each date opens the federal record of that event.
| When | Event | Place named | Harm | What the report says |
|---|---|---|---|---|
| October 2021 | Thunderstorm Wind | Swansea | $50,000 | A swath of damaging winds occurred over St. Clair County from Swansea through O'Fallon, Scott AFB, and Mascoutah. Several large trees were blown down. The roof of a storage building was blown off at Air Force Base Storage. The debris landed on a house east of the storage building near the intersection of Illinois Route 161 and Hannah Chase Court. In Mascoutah, a pole barn was lifted and flipped, landing on a nearby business about 30 feet to the east. |
| May 1995 | Thunderstorm Wind | Swansea | $600 | Numerous power lines and large trees were knocked down across the county. |
| May 2025 | Thunderstorm Wind | East Swansea | - | There were several reports of trees and power lines down over northern St. Clair County. |
| May 2024 | Hail | East Swansea | - | Up to 1 inch hail was reported in Swansea, Shiloh, and Mascoutah. Other locations in the path of the hail include Belleville and Scott Air Force Base. |
| July 2020 | Thunderstorm Wind | Swansea | - | Widespread thunderstorm wind damage occurred from Belleville eastward through Mascoutah. In Belleville, multiple trees were blown down as well as power lines. Also, a couple of buildings sustained minor roof damage. In Mascoutah, multiple trees and tree limbs were blown down throughout town. Also, a tree split with one portion falling onto a house and the tornado siren on top of city hall tipped over. |
| July 2017 | Thunderstorm Wind | Swansea | - | Thunderstorm winds blew down numerous large tree limbs. In Belleville, two large tree limbs fell onto the roof of a house causing moderate roof damage. |
| February 2017 | Thunderstorm Wind | East Swansea | - | Thunderstorm winds blew down a utility pole on the northwest side of town. |
| July 2016 | Thunderstorm Wind | East Swansea | - | Thunderstorm winds uprooted a tree on North Charles Street near intersection with Illinois Route 161. Also, numerous tree limbs were blown down in the area. |
| June 2015 | Thunderstorm Wind | Swansea | - | Thunderstorm winds blew down several large trees and numerous tree limbs around Belleville. Also, a few power lines were blown down. |
| June 2011 | Thunderstorm Wind | Swansea | - | Thunderstorm winds blew down a few trees near the intersection of Illinois Route 15 and Frank Scott Parkway. |
| May 2011 | Thunderstorm Wind | Swansea | - | Thunderstorm winds blew down a couple of trees. One tree landed on West Main Street and the other on Summit Avenue. |
| May 2010 | Hail | Swansea | - | no account filed |
| June 2009 | Hail | Swansea | - | no account filed |
| May 2008 | Hail | Swansea | - | no account filed |
| June 2003 | Thunderstorm Wind | Swansea | - | no account filed |
| August 2000 | Thunderstorm Wind | Swansea | - | no account filed |
Nearest settlements
The eight closest, with where each one stands in the county. Distances are straight-line, computed from the Geographic Names Information System coordinates.
| Map | Place | Distance | Sheets |
|---|---|---|---|
| Belleville | 1.0 miles | 17 | |
| Summit | 1.5 miles | 21 | |
| Royal Heights | 1.5 miles | 21 | |
| Avery Hill | 2.4 miles | 21 | |
| Gartside | 2.6 miles | 21 | |
| Miller | 2.8 miles | 17 | |
| Birkner | 2.9 miles | 21 | |
| Notre Dame | 3.0 miles | 21 |
Elsewhere
Matched on this settlement's Geographic Names Information System number rather than its name, so it cannot be a different place of the same name in another state.
| Wikipedia article on Swansea | An encyclopaedic summary. Its text is share-alike, so it is linked here rather than copied. |
| Wikidata item Q1641936 | The structured record the population and elevation above come from. Public domain (CC0). |
Provenance
This settlement is recorded in the Geographic Names Information System as feature 426552. The sheet list is computed by point-in-boundary test against the United States Geological Survey's historical topographic inventory. Both are works of the United States government and carry no copyright under 17 U.S.C. 105.
Wildfire. Short, Karen C. 2022. Spatial wildfire occurrence data for the United States, 1992-2020 [FPA_FOD_20221014]. 6th Edition. Fort Collins, CO: Forest Service Research Data Archive. https://doi.org/10.2737/RDS-2013-0009.6 Collected with United States Government funding and usable without additional permissions or fees.
Mines and quarries. USGS Mineral Resources Data System (MRDS) https://mrdata.usgs.gov/mrds/ A work of the United States government, no copyright under 17 U.S.C. 105.
Storms. NOAA National Centers for Environmental Information, Storm Events Database https://www.ncei.noaa.gov/stormevents/ A work of the United States government, no copyright under 17 U.S.C. 105. Narratives are quoted verbatim from the National Weather Service report and are not edited or summarised.






