Tag Archives: transportation

Transportation and the Green New Deal

If you follow the people I follow on Twitter, the last few days have included lots of chatter (often pained) about the transportation elements – or lack thereof – in the Green New Deal. Given that transportation is the single largest source of US greenhouse gas emissions (and because the sector relies on direct use of fossil fuels more than, say, buildings), transportation ought to the focus of any climate policy.

So, why isn’t it? The Green New Deal was (and perhaps still is) more of a slogan than an actual policy proposal. Earlier, the think tank Data For Progress released their policy proposal.

The key transportation elements include fairly weak language about increasing “access to” transit and bike facilities, paired with much stronger language about electric cars:

  • 100% Zero Emission Passenger Vehicles by 2030
  • 100% Fossil-Free Transportation by 2050
  • Modernize Urban Mobility and Mass Transit
    The growth of cities, the rapid change in vehicle technology, and the need for low-carbon transportation means that the way in which we move ourselves and goods from one place to another is going to change forever. This transition needs to be executed thoughtfully to meet the needs of cities and the scale of change required. Large investments are needed to increase access to safe pedestrian and bicycle travel, low-carbon bus rapid transit, and electrified light rail.

The twitter commentary jumped all over this: why not address land use at all? Why such wishy-washy language on transit and bikes? Why not mention any host of technocratic ideas and policies that will be useful tools in decarbonizing transportation?

A few arguments in defense of this proposal:

  • These things are popular. Data for Progress has done a great deal of polling and message testing. They make a convincing case that these elements are not just effective, but popular. As important as land use is to addressing climate change, I can understand how it’s not the best item to lead with.
  • Lead with strong messaging. Support among technocrats and wonks is required to execute any idea, but the technocrats are often bad at messaging and not a natural fit to build a successful coalition (Jeff Tumlin has made this point regarding road tolling and congestion pricing)
  • It’s better than anything else on the table. The proposal, as it stands, is light years better than anything else anywhere close to the agenda of anyone in power.

Still, the critiques aren’t wrong, per se.

  • Nothing on land use. Slipping in a plank to abolish single-family zoning might be unpopular (Minneapolis’ recent planning efforts aside), particularly at the national scale.
  • Transportation should be a bigger focus: Alon Levy made a persuasive case here for why the GND must focus on transportation. And, naturally, lots of transportation elements are indeed quite popular – and could be framed to emphasize that popularity.
    • Stronger language for transit and safety mandates (something simple yet radical, like vision zero) could be a more popular way to frame the trade-offs required to meet these aggressive goals.
  • Nothing is free in this world. Leading with a popular message framework for something as big as a new New Deal is by definition incomplete; a first step. But there’s a risk of politicians skipping over the trade-offs required to implement the plan. This might be premature, but something that needs to stay on the radar.

Given how early in the process the GND concept is, we should all give the benefit of the doubt, particularly given Data for Progress’s efforts on polling and messaging. But decision-makers still have to grasp the trade-offs involve.

As an example, read Alissa Walker on California, electric cars, and the disconnect between the Air Resources Board and the state’s Transportation Commission. Both bodies are charged with addressing climate change, but they operate in silos. The Transportation Commission has assumed electric cars will do the trick, while the CARB has done the math, and shown conclusively that electric cars are not enough – the state needs to drive less.

This is the big concern: setting a big goal is vitally important, both because of the scale of the problem and because of the potential motivation for a radical change. But radical change will require trade-offs, and it doesn’t help to mislead the public about the nature of the trade-offs involved – just look at the omnishambles that is Brexit.

More on the geometry of transportation: “Transport is mostly a real estate problem”

In June, the Urbanization Project at NYU’s Stern Center posted several graphics looking at the space devoted to transportation in our cities. As the author, Alain Bertaud, frames it, “transport is mostly a real estate problem.” That is, different transportation modes require different amounts of space to accomplish the same task.

Comparison of population/employee density and street area per person. Image from NYU Urbanization Project.

Comparison of population/employee density and street area per person. Image from NYU Urbanization Project.

Each of the selected examples cluster around the diagonal blue line, representing an average of 25% of a city’s land devoted to streets.

Percent of land use devoted to buildings, streets, etc. Image from NYU Urbanization Project.

Percent of land use devoted to buildings, streets, etc. Image from NYU Urbanization Project.

Two observations: the 25% pattern is remarkably consistent; as is the geometric relationship between modes of transport and the intensity of land use.  The green horizontal lines show how much space a car uses at various speeds – the faster the car goes, the more space it requires. A parked car occupies 14 square meters, while one moving at 30 kph takes up 65 square meters.

The obvious corellation is between a city’s density and its type of transportation network. Cars take up a large amount of space relative to their capacity, and a transport system based on cars alone cannot support a great deal of density.

Alex Tabarrok frames this in terms of “the opportunity cost of streets.” While there is certianly an opportunity cost to various street uses, it’s worth noting that some space must be devoted for streets in order to access property. Charlie Gardner at Old Urbanist takes note that the role of streets is not solely about transportation:

In addition to their transportation function, streets can also be understood as a means of extracting value from underserved parcels of land.  The street removes a certain amount of property from tax rolls in exchange for plugging the adjacent land in to the citywide transportation network.  Access to the network, in turn, increases the value of the land for almost all uses.  For the process to satisfy a cost/benefit analysis, the value added should exceed that lost to the area of the streets plus the cost of maintenance. (This implies rapidly diminishing returns for increasingly wide streets, and helps explain why, in the absence of mandated minimum widths, most streets are made to be fairly narrow.)  For many of the gridded American cities of the 19th century, as I’ve written about before, planners failed to meet these objectives, although these decisions have long since been overshadowed by those of their 20th century successors.

Charlie also notes that many great, dense, walkable cities around the world devote about 25% of their land to streets, yet many American downtowns use a much higher percentage of their land to streets.

Some of those numbers might depend on the exact method of accounting. While Charlie’s estimate for downtown DC shows 43% of the land used for streets, DC’s comprehensive plan shows approximately 26% for the city as a whole:

Land Use Distribution in DC, from DC's 2006 Comprehensive Plan.

Land Use Distribution in DC, from DC’s 2006 Comprehensive Plan.

The graphic doesn’t specify if the street figure refers to street right of way, or just the carriageway portion of the street, but not the ‘parking area.‘ Seattle’s planning documents also showa similar pattern: 26% of land city-wide used for streets, but also a higher percentage of downtown land devoted to streets.

Seattle land use distribution by neighborhood. Image from Seattle's 2005 Comprehensive Plan.

Seattle land use distribution by neighborhood. Image from Seattle’s 2005 Comprehensive Plan.

The Seattle calculation looks at land devoted to right of way for streets, rather than just impervious surface.

Making better or different use of existing right of way is one thing; however, once that right of way is set, it is very difficult to change. Transportation networks awfully path dependent. Chris Bradford looks at Austin’s post-war planning and the abandonment of the street grid – path dependence in action:

Back then, “planning” chiefly meant “planning streets.” It’s a shame that planning lost that focus. The street grid that permeated Austin in 1940  is of course still with us, and forms the backbone for a number of quite livable neighborhoods.

So what happened? Developers building large, planned subdivisions (Allandale, Barton Hills) continued to add decent street networks after 1940. But the City itself appears to have gotten out of the grid-planning business not long after this map was made…

Collectively, these could and should have been platted into 40 or so city blocks. Instead, they remain two big blobs of land. The lack of connectivity funnels traffic onto South Lamar and Manchaca; impedes east-west mobility, dividing eastern and western neighborhoods; forces people to make circuitous trips to run even simple errands; and forecloses any sort of low-intensity, mixed-use development in the area. Then there’s the sheer loss of public space: South Austin should have a few more miles more of public, connected streets than it has today.

Once the street grid is set, it is very difficult to change.

The most segregated cities in America

Salon.com has an interesting slideshow of the 10 most segregated cities in America.  The data comes from the 2010 Census, and the methodology to determine the level of segregation is based on differences between census tracts:

We may think of segregation as a matter of ancient Southern history: lunch counter sit-ins, bus boycotts and Ku Klux Klan terrorism. But as the census numbers remind us, Northern cities have long had higher rates of segregation than in the South, where strict Jim Crow laws kept blacks closer to whites, but separate from them. Where you live has a big impact on the education you receive, the safety on your streets, and the social networks you can leverage.

The following is a list of the nation’s most segregated metropolitan areas of over 500,000 people. The rankings are based on a dissimilarity index, a measure used by social scientists to gauge residential segregation. It reflects the number of people from one race — in this case black or white — who would have to move for races to be evenly distributed across a certain area. A score of 1 indicates perfect integration while 100 signals complete segregation. The rankings were compiled by John Paul DeWitt of CensusScope.org and the University of Michigan’s Social Science Data Analysis Network.

Each of the 10 most segregated cities includes a narrative for the city.  Several include observations on transportation and the linkages between land use and infrastructure.

# 10. Los Angeles

LA 10

The L.A. riots of 1992, like the 1965 Watts riot, were sparked by police brutality, a steady concern in besieged neighborhoods like South Central. Nearly 20 years later, the jobless ghettos of black and Latino Los Angeles remain. Greater Los Angeles has been so big for so long — legion nodes connected by extensive highways — that it’s hard to say exactly what its borders are. Safe in their cars and behind their gates, most white people have gone back to not paying attention.

In short, transportation matters. Diversity without intermingling can be isolating.

# 2. New York
NY 02

Ingrid Gould Ellen, an urban planning and public policy professor at New York University, says that New York City is somewhat more integrated than the data would suggest, because it is far denser than most cities. Since census tracts are made up by population, tracts in New York tend to be very small.

“What happens is that we’re not making apples to apples comparisons. The neighborhoods in Atlanta and Houston are 10 times the size of neighborhoods in New York City physically,” she says. “The census tracts are so much smaller, so you’re likely to cross over a number of census tracts every day.”

The daily commute of the average New Yorker also lessens racial isolation. Thanks to the dominance of public transit, intra-city travel tends to be a diverse experience.

New York, despite segregation, benefits from both density and transit.

# 1. Milwaukee

Milwaukee 01_2

Nationwide, blacks have been concentrated in the inner city, far away from where new jobs are created. Yet the case of Milwaukee is extreme: 90 percent of the metro area’s black population lives in the city. Making matters worse, suburban whites are notably hostile to building any form of public transit to connect city people to suburban jobs, further exacerbating segregation’s ill effects.

If you’re wondering if this can somehow, some way, be blamed on union-busting Wisconsin Gov. Scott Walker, the answer is yes. Walker took the lead in a campaign against public transit to connect the suburbs to the city during his time as county executive. He thought the funds would be better spent on highways.

“There is virulent opposition in these exurban counties to any kind of regional transit system, particularly a regional rail system. There have been proposals over the years, but they’re always DOA,” says Levine. “Governor Walker’s big issue as state representative and county executive was ‘Over my dead body light rail,’ and he fought with Milwaukee’s mayor over funds for regional rail. He very much represents that suburban and exurban base.”

That map graphic says it all.