This is the first in a series of posts on web-based maps developed by the University of Connecticut Libraries Map and Geographic Information Center (MAGIC) for the On The Line project.
Today’s web technology can help us to tell more meaningful and visually engaging stories about the past. During the 1930s, a federal agency (the Home Owners’ Loan Corporation, or HOLC) cooperated with private mortgage lenders to assess investment risks across neighborhoods in over 200 U.S. metropolitan regions. These ratings were not based exclusively on the housing stock, but also on racial, ethnic and social class makeup of the residence. These color-coded maps ranked the safest areas for investment in green and the riskiest in red, which in later years became associated with the phrase “redlining,” or discriminatory lending by geographic area. Although some historians have argued that these HOLC maps were not directly implicated in post-war urban decline, they nevertheless reflect the dominant views of the times against racial and ethnic minorities and lower-income families.
Caption: Click image to explore our web-based HOLC map for the Hartford area.
At MAGIC, we digitized a 1937 HOLC map of the Hartford area (covering the city, West Hartford, and East Hartford) and created an interactive version using Google Maps API, which can be explored at http://magic.lib.uconn.edu/otl/doclink_holc.html. Click on any color-coded region to view the pop-up bubble, with a link to the original neighborhood appraisal report. For example, see how the HOLC field agent described African-Americans, Jews, Italians, and working-class families as negative factors on home values in several areas.
With support from the National Endowment for the Humanities, MAGIC created this and other interactive maps with Jack Dougherty of Trinity College for the On The Line project. This and other maps are freely accessible in a public history web-book, titled On The Line: How Schooling, Housing, and Civil Rights Shaped Hartford and its Suburbs, which tells the story of schooling and housing boundary lines that have divided metropolitan Hartford, Connecticut over the past century, as well as the struggles of ordinary families and civil rights activists who have sought to cross over, redraw, or erase these lines. See other examples of web-based HOLC maps for other cities, such as “Redlining in Philadelphia” (by Amy Hillier), “Mapping Decline: St. Louis and the American City” (by Colin Gordon), “Redlining Richmond” (by Robert K. Nelson), and “T-RACES: Testbed for the Redlining Archive of California’s Exclusionary Spaces” (by Richard Marciano et al.), which also appears in the Los Angeles section of HyperCities.
Technical detail:
This document-linked dual-view map was created through a multistep process. First, Jack Dougherty scanned the 1937 paper map and neighborhood appraisal reports at the National Archives II in College Park, Maryland. Next, MAGIC staff georectified, “heads-up” digitized, and attributed the map into polygons using ArcMap. After creating the shapefile, the symbologies were selected based on the historical map color scheme and converted to a KML file using the ArcToolbox conversion tool.
The mashup was created using Google Maps Javascript API version 3, which allows the KML file to be layered on top of a Google Map. We enhanced the standard mashup by adding a custom search box to locate any address on the map, and customized JavaScript to link controls for zoom and pan for the dual views. The HTML code for the pop-up windows, which links each of the KML areas to a specific PDF document, can be created in Google Earth. All of our web-based maps use open-source code to the maximum extent feasible, and we encourage users to borrow freely and create their own versions. In the near future, a detailed write-up will be provided on the MAGIC website detailing how the interactive web-based maps were created.
Coming next in this series — Neighborhood Change, 1934-Present: A Dual View Map with Linked Controls