Yonah Freemark just launched the biggest expansion of transit network mapping on Transit Explorer and I built a new feature for TE that allows users to visualize the size of a network by decade from 1970 to today.
When looking at a region of the world, change the era of transit network that you’re seeing by selecting a decade from the dropdown menu under the “Change the era” heading. In a moment, the map will automatically refresh.
I’ll show you three cities:
Salt Lake City
Hong Kong
São Paulo
Salt Lake City
The Utah Transit Authority opened its first modern light rail line in 1999 from Salt Lake City to the southern suburb of Sandy. It opened the second line, from downtown Salt Lake City to the University of Utah, in 2001, in time for the 2002 Winter Olympics. Some games and ceremonies were held at the university. FrontRunner commuter rail opened in 2008, and the third light rail line, to the airport, opened in 2011 and various line extensions opened in 2013. A BRT route that opened in 2018 in Provo is also mapped but not shown while a BRT route in Salt Lake City is shown under construction in 2024.
In 1970, the only rail transit that Hong Kong had were a tramway on Hong Kong Island and the East Rail Line, which opened in 1910 and was electrified in 1983. Every decade since there was a new line or two on the Hong Kong MTR network, culminating in the ten lines you see in 2024.
In 1970, São Paulo’s metropolitan network, Metrô, didn’t exist, but it had six regional train lines operated by three railroads – these kinds of trains are shown in brown on Transit Explorer. The metro, shown in blue, began in 1974, and now has six lines (including one monorail line) while the regional train network was modified to five lines. São Paulo saw its first bus rapid transit (BRT) line added in 1988, but added four more BRT lines since then – just five of the over 900 bus routes operated by EMTU.
How many houses, buildings, units, and lots are vacant in Chicago depends on how you measure them. I’m aware of at least five ways to measure housing vacancy, using publicly available data, each with varying degrees of accuracy and coverage.
Each measurement method has its own TAKEAWAY so you can quickly scan to see how many units are potentially vacant. The bottom line, I believe, is that the vacancy rate in Chicago is quite low and vacant units is not a viable and scalable source for the additional housing that Chicago needs. However, I am compelled to add that it’s unclear how many additional homes Chicago needs because there are no analyses that uncover the shortfall or recommend a goal production number.
1. Vacant units, per Census bureau
The US Census Bureau says there are 1,258,704 dwelling units in Chicago, and that 10.2% of them are vacant (128,796 units). The Census bureau has two types of vacant, which generally break down into “listed for rent or for sale and temporarily unoccupied” and “all other reasons”. This data comes from American Community Survey (ACS) 5-year survey.
The Census says 37.3% of Chicago’s vacant units are “temporarily unoccupied” (38,450 units) and 62.7% are vacant for “other reasons” (64,589 units). This data comes from ACS 1-year data, which has larger margins of error than the 5-year survey data. The “other reasons” are what I am calling “truly vacant”.
The most common survey response within “other reasons” is that the unit is currently being renovated or repaired (20.2%). Additional top “other reasons” are:
Currently being renovated/repaired: 20.2%
Personal/family reasons: 15.6%
Needs repairs: 14.6%
Preparing to rent/sell: 13.1%
Abandoned/possibly condemned: 10.1%
Up For Growth, a national policy organization, has assessed that Chicagoland has an underproduction of 129,218 homes (using 2019 data), and about 3.3 percent of the existing housing stock in the region. Assuming that 80 percent of this underproduction is “assigned” to the City of Chicago, then this underproduction represents about 1.6 times the number of vacant units (vacant for any reason in the Census Bureau’s survey) that likely exist in Chicago.
TAKEAWAY from #1: Fewer than all 64,589 units are “truly” vacant, however. About 21,508 of those units are purportedly being renovated or repaired and will be rented or sold soon.
A large number of the remaining 43,081 “truly” vacant units are unlikely to join the rental or sale market soon. Assuming that all of these 43,081 vacant units are rented or sold then Chicago, using that 80 percent assignment of the 129,218 underproduction, would still have an underproduction of 60,294 homes.
2. Vacant units, per Chicago’s Vacant Building Registry
From a February 2023 snapshot of the Chicago Vacant Building Registry, which requires landlords to register buildings as vacant once they are vacant for more than 30 days, there were 6,521 dwelling units that were reported by owners as vacant. Comparing this to the above Census bureau figure that nearly 65,000 units are truly vacant, this would mean that 90% of vacant units are not registered in the VBR.
The reasons for vacancy were not included in the VBR data I received from the city. Also, these units are likely already included in the Census figure above and not in addition to.
TAKEAWAY from #2: There are at least 6,500 vacant dwelling units in Chicago.
3. Buildings reported as vacant to 311
Chicagoans can report to 311 that they suspect a building to be vacant. There is no link to building violation citations or feedback on these reports as to whether the suspicion was founded by a city worker.
Notice how the number of reports dropped by about half from 2022 to 2023. I don’t know if there are fewer suspected buildings to be reported, fewer people are reporting buildings, or there are barriers to reporting and collecting the reports.
TAKEAWAY from #3: This data is probably not reliable to understand the number of vacant buildings in Chicago.
4. Buildings cited as needing to be registered in the Vacant Building Registry
In 2023, Chicago Department of Buildings inspectors cited 24 buildings with a violation for not being registered in the Vacant Building Registry.
TAKEAWAY from #4: If about 90% of vacant units are not registered then there are drastically few citations being issued to force registration.
5. Vacant lots, per Cook County Assessor Office
The CCAO classifies nearly every property in Cook County. The classification 1-00 represents vacant lots. At present there are 32,207 vacant lots in Chicago. 22,645 of these (70.3%) are in “R” zoning districts and allow only residential uses. Another 4,566 lots (14.2%) are in “B” and “C” neighborhood mixed-use zoning districts.
TAKEAWAY from #5: Tens of thousands of new construction homes could be built on vacant lots.
Addendums
In its Chicago monthly market update (from January 2024) for the multifamily housing sector, Colliers brokerage reported that the Chicago MSA “has a vacancy rate of 5.3%, which is below the national rate of 7.6%”.
Brookings Institution posted an article (in October 2024) describing other sources for housing shortage estimates, from The National Association of Home Builders (NAHB), Freddie Mac, Moody’s Analytics (Mark Zandi), and National Association of Realtors (NAR). Brookings found that, nationally, the United States is short 1.5 to 5.5 million homes, according to the four sources.
A 2018 article from Freddie Mac determined that “the current pace of building is not enough to meet demand” and that 370,000 fewer units were built in 2017.
Illinois has a statute that requires every covered municipality to have an affordable housing stock of 10 percent relative to its total housing stock. The Affordable Housing Planning and Appeal Act exempts only municipalities with population of under 1,000, and those “in which at least 10% of its total year-round housing units are affordable, as determined by the Illinois Housing Development Authority”.
IHDA updates a list of non-exempt municipalities – those not achieving the 10 percent standard – every five years, which it last did in December 2023 (the list of non-exempt local governments, or NELGs, and the full list of all municipalities).
List of 44 non-exempt municipalities ordered by lowest percentage of housing stock which is affordable.
Glenview is one of the non-exempt municipalities and this year has “had trouble” approving new housing. Although neither proposed development included affordable housing, to my knowledge, the developer of one proposal said that the project rents would be less than the median; my guess is that most rentals in Glenview are not other apartments but whole houses.
I’ve been keeping a list, on Twitter, of other municipalities that have “had trouble” approving new housing.
One of the updates in the AHPAA adopted in 2023 is that the definition of who can appeal a municipality’s rejection of a proposed affordable housing development has been expanded to, basically, include someone who could have lived in the development if it was built.
The revised definition for appellants also includes housing advocacy organizations that have an overlapping geographic focus. This new appellant definition takes effect on January 1, 2026.
IHDA’s FAQ answer to who is an appellant and can appeal a rejected affordable housing development proposal.
If you know of an Illinois municipality that has voted to reject an affordable housing development, or has through some kind of delay or inaction effectively rejected an affordable housing development, please let me know!
On Monday, December 4, 2023, I wanted to ride a line in the Netherlands that I hadn’t yet, which is called the “MerwedeLingelijn” and goes between Dordrecht and Geldermalsen. In the NS journey planner database it’s called “Stoptrein” which distinguishes it from “Sprinter” and “Intercity”. Those names distinguish the service types on the Dutch railway network. (This particular Stoptrein is also a diesel-electric trainset.)
From Rotterdam, where I was staying, it would require at least one transfer to get to Gorinchem. But I wanted to stop in Utrecht to say hi to a friend during his work break – this meant there would be two transfers.
Here’s the itinerary I traveled on Monday
Rotterdam Centraal to Utrecht Centraal via Gouda, Intercity (half-hourly service) – 55 km
Utrecht Centraal to Geldermalsen, Sprinter (10-20 minute service) – 26 km
Geldermalsen to Gorinchem, Stoptrein (half-hourly service) – 27 km
[lunch and walk in Gorinchem, distance not recorded]
Gorinchem to Dordrecht, Stoptrein (quarter-hourly service) – 24 km
Dordrecht to Rotterdam, Waterbus (hourly service) – 21 km
How I drew the map
I wasn’t about to draw the routes by hand (although I did record the Waterbus ride on Strava as a “sail”) so I grabbed the data from OpenStreetMap.
If you want data in bulk from OpenStreetMap a common way to get it is from the HotOSM export tool. But I wanted specific transit routes, for which I could find the “way” IDs and export only those. For that I used Overpass Turbo and wrote the following query:
Frequencies refer to the pattern in the hour I used the service. The itinerary doesn’t include a Rotterdam Metro ride or the roundtrip bike ride from the Schiebroek neighborhood to Rotterdam Centraal).
Starting on December 10, the NS (Dutch national railway operator) is adding over 1,800 train services each week.
Climate-fi is a genre of novels in which the effects of climate change are central to the plot. I have become more of a fan of climate fiction commensurate with the frequency of books being published.
The first climate-fi story I read – before I knew the genre name – was “The Water Knife” by Paolo Bacigalupi. That came out in 2015 and it wasn’t until 2020 that I picked up the genre again.
Here are books I recommend:
The Water Knife explores the realistic issues of freshwater supply and who has the right to water sources in the Southwest. This is especially relevant to problems and discussions today, given that people in Arizona are having to buy water from the private market, governments are not approving proposed developments unless they come with new water sources, the state continues to usurp water from upstream freshwater sources, land use is single-use and sprawling, and historic water rights are still a source of conflict.
Parable of the Sower, by Octavia Butler. The protagonist and her family live in a tenuous gated community in the near future of a United States ravaged by climate change and other economic and political upheavals. She eventually travels towards a place to establish a better community based on a religion she invents.
Ministry for the Future, by Kim Stanley Robinson, opens in the “almost present” day describing a heat wave in South Asia during which the wet bulb temperature challenges the body’s ability to cool itself and many people die. A climate terrorist group forms to force the world to adapt to and mitigate climate change globally otherwise the poorest people will suffer the most during the crisis. (KSR personally sees cities as a climate change solution.)
Termination Shock by Neal Stephenson opens with a riveting story of the Dutch queen’s plane crashing in Texas and then winds around the world narrating seemingly unconnected climate change-related events. The story then focuses on how shooting sulfur into the atmosphere has an effect on how much energy of the sun reaches Earth, something that actually happened last year.
What climate fiction books and stories do you recommend?
