TOD is Transit-Oriented Development. TARTAURR is 'Transit-Accelerated Redevelopment Through Accessibility Upgrades and Regulatory Relief". And when planners use TOD as a planning framework, they really mean TARTAURR.
The amount of actual TOD anywhere is pretty minimal. Do a deep read of The Next American Metropolis and you'll find out that TOD is not at all what you thought it was. Every Calthorpe style TOD is a megadevelopment:
"A megadevelopment is a very large-scale real estate or infrastructure project, often costing billions, spanning significant land areas, and integrating multiple uses such as residential, commercial, and retail spaces" - Copilot
Megadevelopments:
- 1. Cover large tracts of land (often hundreds of acres) [1]
- 2. Involve billions of dollars in investment
- 3. Combine multiple functions (housing, offices, retail, amenities, public space)
- 4. May include infrastructure such as transport systems, parks, and amenities
Sound familiar? It should:
Calthorpe is an architect, and architects work for clients, and their clients are: 1) rich individuals, 2) wealthy corporations, or 3) developers. Calthorpe's milieu is #3--recall that the other thing he's famous for is Seaside, which is very much NOT a TOD. It's a megadevelopment, for megadevelopment reasons. Which are, per Copilot:
Why Megadevelopments Are Built
- Demand for mixed-use urban living: Developers respond to interest in walkable, amenity-rich environments.
- Efficient land use: Particularly in dense or post‑industrial urban areas where large tracts can be repurposed.
- Economic strategy: Diversifying uses reduces risk and attracts a broad demographic
So while the format of TOD is urban living, its location is defined where large tracts can be repurposed, and the mix of uses is partially a capital/financing approach to dealing with market uncertainty over a long development timescale.
What TOD is not: Transit-Accelerated Redevelopment Through Accessibility Upgrades and Regulatory Relief (TARTAURR). Which is how people keep trying to use it and keep being puzzled when it doesn't fit.
To unpack TARTAURR, it breaks down into three parts: 1) Transit Accelerated Redevelopment, 2) Accessibility Upgrades, 3) and Regulatory Relief.
Transit-Accelerated Redevelopment
I've written previously regarding the role of public investment in spurring redevelopment, with the conclusion that public investment doesn't really change how much development you get--it only determines the where. Every bit of real estate is just a decaying pile of sticks and bricks, metal and stone. In a functional real estate market [3] developers are always prowling around looking to buy up the most-run down real estate they can find, so they can knock it down and build something bigger and higher rent. Because the land is valuable, and they want to take advantage of that. How likely that is to happen is a function of two things: how run-down the building is and how much the land underneath it has appreciated. Public policy can't do much within those constraints. Bricks and sticks break down on their own schedule, and land value only grows with as population demand for housing does. Except...
Accessibility Upgrades
For urban land, all the value is in the location. The value of a strand of trees, or clay pit or even oil well is limited. Each produces a stream of rents. The summation of the stream of rents is the value of that land. The market is indifferent to the source of the stream of rents, and when the stream of rents called "new houses" is larger than the one called "farmland", land gets developed. The viability of aforesaid new houses is based on people being able to get from those houses to other things, most critically jobs, by which people exchange labor for money, and are able to pay rent. For 99.9% of human history, access meant 'you can walk there and back' for almost everyone (horses were expensive). French polymaths aside, humans invented photography before we had a reasonable alternative. But once we invented the magic machine that was the railroad, areas far beyond a reasonable walk became accessible. And lo, the farmland out there was transformed into houses by becoming accessible. The more accessible urban land is, the more valuable it is, and the more worthwhile it is to invest in things like staircases, proceeding onward that way until you have 16 story masonry(!) buildings with walls 20' thick.
Tangents aside, urban economics has long been pretty clear that if you want an area to develop, making is accessible is a pretty good way to do that, and railroads and streetcar operators made a lot of money doing real estate development on that basis, for some decades. So the concept that adding a rail station would make urban land more valuable was not a big stretch. From 1970 on, automotive traffic congestion was steadily reducing travel speeds by car and previously marginalized urban transit systems started to look reasonable again. And with that, so did adding new stations. Extend some existing lines, add some infill stations, re-activate some abandoned lines. Eventually, such opportunities ran out, and someone suggested if we build some new rail systems, we could curve congestion in new places. The Germans had figured out how to leverage their own post-industrial patrimony by converting freight rail lines to light rail, and America did the same thing.
The plan is simple: build a rail line, add a station in a run-down neighborhood. Land with depreciated structures became more valuable, and is redeveloped into higher-rent buildings, the people in those buildings were more affluent, they both spent money locally and advocated for their new neighborhoods, and everyone is happy [4].
Regulatory Relief
Zoning is oriented toward new development. Most new development is suburban and auto-dependent, and the regulations devised to manage it reflect that. Destructively, suburban zoning was applied not only to developing areas, but to already developed areas. Parking mandates, height limits, setback requirements, unit count limits were all applied uniformly, maliciously [5]. But as anyone doing infill and redevelopment, can tell you, there is no reason for it. Adding a new townhome next to an existing townhome should not be illegal. Applying fire setbacks to brick structures is absurd. Requiring three parking stalls for three bedrooms is unkind to families.
The travel behavior of households living in dense, mixed-use urban environments is different than that of the same family in a suburban cul-de-sac. People walk more, take transit, drive less and own fewer cars. They live in different types of houses. And so it became possible to petition for relief from such standards, as context specific variances to zoning code. That regulatory relief made it possible to build at higher densities, and for urban real estate to provide higher rents. Regulatory Relief can only questionable be justified. There is certainly evidence indicating that the dense, walkable, mixed-use environments are what causes the reductions in driving, and that transit is actually a spandril.
The TOD paradigm enters the chat as a mechanism for managing the conflicts over variances permitting higher density, for regulating where the new, higher density development would be considered politically justifiable.
TARTAURR
1) Transit Accelerated Redevelopment
2) Accessibility Upgrades, and
3) Regulatory Relief
It is not TOD, but TARTAURR, that is the model most public agencies and transit planners use for developing around most transit stations. TODs do exist, but their scarcity is such that in terms of the universe of transit station areas, they can be considered an aberration.
Two additional acronyms to dispatch: TAD and TOC. TAD, "Transit Adjacent Development", "TOD's evil twin' is actually the norm for most transit stations. Land use development predates the transit station, rather than in response to it. And the combination of rising land values and depreciating sticks and bricks respond slowly to the new situation, with changes taking decades to play out. Regulatory relief can accelerate the transition, but only so much.
Regarding, TOC, it was the wild success of the Portland Streetcar made it possible to reframe TOD strategy as 'Transit-Oriented Corridors", where the accessibility upgrade radiated outward from a line because of overlapping access created by closely spaced stations [6]. But recall that the Pearl District was a key part of that success, and that the Pearl District was.... a megadevelopment! (Yes, it was also a TOD, but the point I'm making here is that every actual TOD is also a megadevelopment).
Hence, to make the best use of the public investments in fixed guideway transit, we need to stop pretending we're going to do TOD at all the stations, and focus on how to best make TARTAURR work best.
#--------------------------------------------------------------------------------------------------
[1] New American Metropolis actually says "a ten-minute walk" which at 3mph is a half a mile, from which everyone implies TOD is a half-mile buffer, which relies on the assumption of a uniform direct path from the station to everywhere within a half mile, which is would be a parking lot, which would be absurd. So the 400 acres for a half mile is actually only about 150 acres for 2000' feet, and the TOD diagram only uses half a circle, so a TOD might be termed 'a small megadevelopment'.[5] Downzoning is the urban version of exclusionary zoning; it reduces permitting densities below that of existing development, in a bid to prevent new development, and thereby thwart new development that might induce competition for street parking.
[6] Tangentially, also the theory of bus service by people who don't ride buses, and so don't understand that more stops means slower travel, and that the incremental improvement in having a bus stop 300' closer isn't worth making a commute 30 slower.