Redlining and Urban Heat Islands

In the 1930’s the Home Owner’s Loan Corporation of America (HOLC) created actuarial maps of the United states. These maps were color coded — Green, Blue, Yellow, and Red — to reflect the amount of “risk” associated with home loans in those areas. The colors corresponded to “Best” (green), “Still Desirable” (blue), “Definitely Declining” (yellow), and “Hazardous” (red). Being in a green area made you likely to secure a federally-insured home mortgage, something that was effectively unavailable to red areas. Red areas were often associated with black populations, and these maps are where the term “redlining” comes from.

Here’s an HOLC map of Arlington, courtesy of the University of Richmond’s mapping inequality project.

"Redline" map of Arlington, MA, courtesty of the Home Owner's Loan Corporation
HOLC “redline” map of Arlington, Massachusetts

Note that Arlington does not have any “Hazardous” (red) areas; 68% of the town fell into the top two grades, meaning that we were generally a safe bet as far as federal mortgage insurers were concerned. To the extent that the HOLC preferred white communities, Arlington seems to have fit the bill. According to US census data.

  • 1930: population 36,094. No breakdown by race.
  • 1940: population 40,013. 99.8% white.
  • 1950: population 44,353. No breakdown by race.
  • 1960: population 49,953. 99.7% white.
  • 1970: population 53,524. 99.0% white.
  • 1980: population 48,219. 97.3% white.

Today, Arlington is about 84% white. But during the time that mortgage approvals were based on the HOLC maps — the mid 1930’s through the mid 1960’s — we certainly qualified as an overwhelmingly (> 99%) white community.

Arlington had four yellow-lined (“definitely declining”) areas; about 32% of the town. C1 (on the western edge of town) was noted for an “infiltration of Jews”, a “heavy concentration of relief families”, and hilly terrain which was “not conducive to good development”. But it had good schools and a nice area along Appleton St. C2 (along Mass Ave and Mill Brook) was noted for “obsolescence” with “business and housing mixed together” and “railroad tracks through [the] neighborhood”. There was an infiltration of lower-class people, a moderate number of relief families, and “little possibility of conversion of properties to business use”.

C3 (East Arlington, around the present location Thompson School and Menotomy Manor) was noted for “Obsolescence, poor reputations” and “foreign concentration”. There was an “infiltration of foreign [residents]” and a “heavy concentration of relief families”. On the positive side, there were “a few small farms in this section of high grade development of the ground [which] may be anticipated in the early future with modest houses”.

Finally, C4 (around Spy Pond, and near the Alewife T station) was “obsolescent”, with an infiltration of foreign families, and a moderately heavy concentration of relief families. The HOLC noted that “Houses East of Varnum Street [and] south of Herbert Road are built on low ground and many have damp basements which makes them difficult to keep occupied”.

That’s what the HOLC saw as the declining side of Arlington: Jews, foreigners (mostly Italian), relief families, obsolescence, damp basements, and proximity to the Boston-Maine railroad.

Exercise for the reader. Arlington has five public housing projects: Drake Village, Winslow Towers, Chestnut Manor, Cusack Terrace, and Menotomy Manor. What HOLC colors are associated with our public housing?

Buildings last for decades, and effects of the HOLC’s underwriting policies are still with us today — sometimes in unexpected ways. A 2020 paper called “The Effects of Historical Housing Policies on Resident Exposure to Intra-Urban Heat: A Study of 108 US Urban Areas” examined 108 communities, and tried to determine if there was a relationship between redlined areas and urban heat islands. Nationwide, this is what they found:

Land surface temperature as a function of HOLC risk category
Land Surface Temperature, by HOLC risk rating

LST stands for “land surface temperature” and shows how different HOLC risk categories compare to the overall temperature of a region. Green areas tend to be cooler, with less paved surface, more extensive tree canopies, and buildings with reflective exteriors. Red areas are warmer with more paved surfaces, less tree canopy, and building exteriors that absorb and release heat (e.g., brick and cinderblocks). While the degree varies across different parts of the country, the general trend is the same: as one goes from green to red, the surface temperature goes up. Formerly-redlined areas are far more likely to contain heat islands.

Exercise for the reader. Are there heat islands in Arlington? What (HOLC) color are they?

As the global temperature warms, Arlington (like many other communities) will have to contend with heat islands. The treatment is likely to be area-specific, following patterns laid out in the HOLC’s maps from the early-20th century.

Improving Residential Inclusiveness, Sustainability, and Affordability by Ending Single-Family Zoning

(Contributed by Ben Rudick and Steve Revilak)

We should end exclusionary Single Family Zoning in Arlington. This is inspired by Minneapolis which ended Single Family Zoning city-wide last year, as Oregon did. To be clear, we’re not suggesting an end to single family homes, only to exclusionary Single Family Zoning; you can still have a single-family house, but now you’d have the option to build a two-family or duplex instead.

79% of all residential land in Arlington is zoned exclusively for single family homes (in the R0 and R1 districts), meaning the only legal use of that land is for a single home built upon a large lot (source: Arlington GIS via the Department of Planning and Community Development). This is a problem for three key reasons:

  1. Single Family Zoning has a deeply racist past. It came into being after a 1917 Supreme Court ruling made it illegal to have “Whites only” neighborhoods. Instead, towns and cities, as encouraged by the federal government, enacted zoning that used economics instead of explicit racism to segregate neighborhoods. A popular strategy was to require large lots on which only expensive, individual homes could be built. Here’s an excellent short video on the topic: https://www.segregatedbydesign.com/
  2. It’s terrible for the environment. Living in a Single Family Home is akin to driving alone instead of carpooling or taking the bus: it’s the most carbon-intensive way to put a roof over your head. The more people you can house in the same structure, the less energy you spend per person. By spreading people out, we’re increasing the amount we drive and the carbon we emit. And we’re contributing to traffic congestion too.
  3. Arlington is becoming increasingly unaffordable. We have a massive (and growing) housing shortage; combined with continued job growth in the Greater Boston area, housing has gotten dramatically more expensive over the last 20 years. The only way for us to keep rising home prices in check is to significantly increase supply, which will be extremely difficult to do while keeping so much of our land reserved for single family homes.

If you’d like to support us, please share this post and join our Facebook group, Arlington Neighbors for More Neighbors, where we’ll post updates and hearing times for the warrant article we’ve submitted to effect this change.

“Surging Seas” Risk Zone Map Shows Arlington Wetlands Threat

Climate Central’s Surging Seas global Risk Zone Map provides the ability to explore inundation ​risk ​up to 30 meters across the world’s coastlines as well as local sea level rise projections at over 1,000 tide gauges on 6 continents.

Set the map for Boston MA and focus in on the Arlington area to see how the town would be affected by rising sea levels, as predicted over the next few decades.

Map areas below the selected water level are displayed as satellite imagery shaded in blue indicating vulnerability to flooding from combined sea level rise, storm surge, and tides, or to permanent submergence by long-term sea level rise. Map areas above the selected water level are shown in map style using white and pale grays. The map is searchable by city, state, postal code, and other location names. The map is embeddable, and users can customize and download map screenshots using the camera icon in the top right of the screen.

For map areas in the U.S., the Risk Zone map incorporates the latest, high-resolution, high-accuracy lidar elevation data supplied by NOAA, displays points of interest, and contains layers displaying social vulnerability and population density. For map areas outside the U.S. the map utilizes elevation data from NASA’s Shuttle Radar Topography Mission (SRTM).

Arlington wetlands on interactive map set to show future 8 foot water rise.

https://ss2.climatecentral.org/?#13/42.4074/-71.1100?show=satellite&projections=0-K14_RCP85-SLR&level=8&unit=feet&pois=hide

Reinhardt on Sustainable Housing Ideas

Prof. Christophe Reinhardt runs the MIT Sustainable Design Lab.  On Nov. 25, 2019 he gave a very interesting presentation, including talk and slides, that shows a pathway to make more housing, all kinds of housing, and greater housing density both more palatable in Arlington, and actually desirable.  He also stressed the importance of paying attention to housing now in order to meet the climate change challenge. Charts (starting about 10 min in) show how drastically we need to reduce our carbon footprint to reach net zero by 2050. Buildings today account for about 40% of our carbon emissions world wide. What we build today will likely be around through 2050.

Paying attention to housing design is important to create a sustainable environment.

Here is the link for the Reinhardts talk and slide show:
http://scienceforthepublic.org/energy-and-resources/designing-sustainable-urban-development

or see it on youtube: https://youtu.be/YAeCvUZmUrI

He uses research, drawn from around the world and locally, to show what measurable attributes make local communities desirable to live in and what attributes of housing make residents happy. 

Key attributes for success (slide is at about 18:15 min. in presentation):

1.  Economic opportunities (proximity to work opportunities)

2.  High quality living (daylight access for buildings, streets, walkable, mixed use, micro-units, vibrant public spaces, organic food, fitness opportunities)

3.  Sustainability (comfortable work and play and living spaces, resource efficiency)

The presentation was arranged by the Robbins Library. It was developed and recorded by Science for the Public as part of it’s lecture series.

For more information on sustainability and cities, cities and local municipalities are beginning to recognize the important linkages between urban resiliency, human well-being, and climate change mitigation and adaptation activities. https://news.mongabay.com/2019/11/how-cities-can-lead-the-fight-against-climate-change-using-urban-forestry-and-trees-commentary/ Courtesy of Science for the Public Interest Weekly News Roundup.


(For more opportunities to learn about sustainability, buildings and cities, sign up for the FREE MITx “Sustainable Building Design” online course which starts January.)