South Central Connecticut Planning Region Map with Towns and Land Area
| County | Population | Land area | Polygon area | Difference | Density | Share of county |
|---|
Boundaries and land area: United States Census Bureau, TIGERweb, public domain. Population: 2020 Census of Population and Housing. Aerial imagery: United States Geological Survey, The National Map, public domain.
How to use this map
The map opens on the Divisions view with all 15 of South Central Connecticut Planning Region’s municipalities drawn straight from Census boundary files. Click any one to pin it and read its figures: land area in square kilometres, 2020 population and the density that falls out of those two. The tabs above the map change what the shading means. Divisions gives each unit its own colour so you can tell neighbours apart at a glance. Land area shades by size. Satellite drops one metre aerial imagery under the boundaries. Blank outline strips the fill away for printing or tracing.
The figure people misread is land area. Census land area excludes water, so a municipality with a lake or a river frontage looks smaller in the table than it does on the map. Branford is the clearest case here: its boundary encloses 72.4 square kilometres but only 56.57 of that is land, leaving 15.83 as water. If you are measuring something that sits on the ground, use the land figure. If you are measuring something that follows the boundary, use the polygon.
What this planning region is made of
South Central Connecticut Planning Region holds 15 towns. Guilford is the largest by land area at 121.93 square kilometres and West Haven the smallest at 27.84, which makes the largest roughly 4.4 times the size of the smallest. The median sits at 56.57 square kilometres, so the spread is wide but most units cluster nearer the middle than the extremes.
New Haven is the largest by population at 134,023, about 23 per cent of the planning region total. New Haven is the densest at 2,768.5 people per square kilometre and Bethany the emptiest at 97.1, a ratio of about 29 to one. Bethany has 5,297 people.
Across the whole planning region the density is 599.8 people per square kilometre. That is the number to hold on to, because it explains the shape of the map: a few dense nodes and a long tail of thinly settled ground, with the average describing almost none of the individual units.
Where the data comes from
Boundaries come from the Census Bureau TIGERweb planning region subdivision layer, which is the authoritative source for municipal geography in Connecticut. Land area is the Census land measurement, which excludes inland water. Population is the 2020 Decennial Census count for each municipality.
The sources are joined on municipality name, and that join is worth checking rather than trusting. The 15 land areas sum to 951.17 square kilometres against a published planning region land area of 951.18, which agrees to the hundredth. The 15 populations sum to 570,487, which is the published planning region total to the person.
Aerial imagery, and how it is fitted to the map
The Satellite tab pulls one metre aerial imagery from the USGS National Map. One metre means each pixel covers roughly a square metre of ground, so at full zoom you can pick out individual buildings, field boundaries and the line of a farm track. That resolution matters at this scale. The national and state maps on this site use a NASA composite at five hundred metres per pixel, which is fine for showing where Connecticut sits in the country and useless for showing where a municipal line runs.
The boundaries are drawn in an Albers equal area projection fitted to this planning region, with standard parallels set inside its own latitude range. Equal area matters here because the map is shaded by area: if the projection distorted area, the shading would be lying. The imagery arrives in Web Mercator and is reprojected to match.
A check you can repeat on paper
Take New Haven. Its land area is 48.41 square kilometres and its 2020 population is 134,023. Divide 134,023 by 48.41 and you get 2768.50 people per square kilometre, which is what the panel shows rounded to 2,768.5.
Now check it against the planning region. New Haven holds 23.5 per cent of the 570,487 people on 5.1 per cent of the 951.17 square kilometres. That gap between population share and land share is the whole story of the map in one comparison.
Mistakes that catch people out
Reading polygon area as land area. The map draws boundaries, and boundaries include water. This planning region encloses 1,004.21 square kilometres of polygon against 951.17 of land, so 53.04 is water, about 5.3 per cent.
Assuming a city is bigger than a town. In Connecticut those words describe charter type, not size. West Haven town is the smallest unit here at 27.84 square kilometres.
Expecting the average to describe a unit. At 599.8 per square kilometre the planning region average sits between Bethany at 97.1 and New Haven at 2,768.5, and matches neither.
Assuming municipal lines follow roads or rivers. Many were surveyed as charter grants or survey townships long before the roads existed. The straight lines on this map are the original survey, not modern infrastructure.
Related Calculators and Reference
- Connecticut County Map, for all 9 counties and where South Central Connecticut sits among them
- United States Map, for the national view and how Connecticut compares
- Massachusetts County Map, for the same treatment applied to another New England state
- US Census Bureau Geography, the source for boundaries, land area and population
