The shape of Portland's peninsula changed dramatically over the past two hundred years as its shoreline was repeatedly reconfigured by in-filling. These composite maps, created by Rosemary Mosher with Geographic Information Systems (GIS) technology, combine historical maps with aerial photographs to retrace the peninsula's expansion. Several major land fills extended the urban core into Portland Harbor and up the Fore River to support commercial and industrial enterprises. New residential property was created by filling in the Back Cove. The transportation network of streets, railroads, and interstate highways kept pace with the demands imposed by increasing population and accompanying real estate development.
The baseline image for this time series spanning some ninety years is taken from the 1777 edition of Des Barres' chart of Portland Harbor [see #5] which is overlaid with CITIPIX Ortho-rectified Digital Images (ODI) from 2001. The purple shading shows the extent of filled land at each point in time. The red shading shows the inhabited areas at each time period. The ambitious grid pattern of streets laid out for the Eastern Promenade (1823) and Western Promenade (1852) never fully materialized as proposed on these maps.
Composite Maps from 1823 to 1917
These two graphical representations reveal the peninsula's expanding shape and the growth of the urban core over two centuries beginning in 1777. Portland's Shape, which incorporates data layers extracted from the time series with GIS technology, traces the historical growth of the peninsula to about 1980. Urban Growth uses data layers of the inhabited areas to illustrate the city's population growth to about 1917.
Portland’s Growth & Expanding Shape from 1777 to 1917
This series focuses on the Deering Farm (the present location of the University of Southern Maine's Portland campus), as depicted in an 1843 manuscript map. It traces its development from an outlying farmstead into an urban campus with the creation of the campus of the Portland Junior College (founded in 1933), which acquired the former Deering Estate in 1947. The yellow shading shows the location of USM owned properties. The red shading indicates present day streets as of 2004. The proposed University Commons expansion for the Portland campus is situated between Bedford and Winslow Streets and is anchored between the Glickman Family Library to the Abromson Center. This plan recalls the site's pastoral forbears/origins with the double row of proposed trees and generous amounts of green space, while at the same time the plan acknowledges its metropolitan location at the crossroads of two of the city's busiest thoroughfares, I-295 and Forest Avenue.
1843 MS map of Deering Farm now the USM Portland Campus.
Courtesy of Maine Historical Society