Tag Archives: tradeoffs

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.

Parking tradeoffs – on-street and off-street

Requiring developers to build off-street parking is expensive.  That’s the key takeaway from a City of Portland study on the impacts of parking requirements on housing affordability. (This study was linked to in a previous post)  To illustrate the point, the city looks at a hypothetical development and considers a number of different scenarios for providing parking to the building.  The results show the trade-offs involved.  The method of providing parking not only adds to the cost, but also limits the ability of a building to fully utilize a site.

For example, providing parking via an off-street surface lot is rather cheap to build, but has a high opportunity cost – that land used for parking cannot also be used for housing. The study keeps the land area and the zoning envelope constant: that is, the off-street parking must be provided on-site, and you can’t get a variance for extra building height.  The trade-offs for this hypothetical development, then, are between cost (and the rent you’d have to charge to get a return on your investment) and in utilization of the site.

Assumed cost per parking spaces are as follows:

Surface $3,000
Podium/Structured (above ground) $20,000
Underground $55,000
Internal (Tuck Under or Sandwich) $20,000
Mechanical $45,000

Apply those options to a hypothetical development site, and you can see the trade-offs emerge.  In every case, requiring parking means fewer units can be developed, and each of those units is more expensive to provide.

Requiring parking makes all of the apartments more expensive, but for different reasons.  The surface parking is cheap, but the real reason the  rent is high is due to the opportunity cost – the surface parking option only allows for the development of 30 units instead of a hypothetical max of 50.

Underground parking is also substantially more expensive in terms of rent, but also in terms of construction costs – the rent increase isn’t that much higher than the surface option (in spite of the $50k per space cost differential) due to the fact that underground parking allows for substantial utilization of the site.   Even underground parking does not allow for full utilization, as the ramps to the garage take up space that could be used for housing in the no-parking scenario.

Requiring developers to add parking in all of these cases jacks up the rent they must charge to make these developments pencil out.  The underground parking example is a 60-plus percent increase in the monthly rent – and it’s a dollar figure that probably ensures that a developer couldn’t just rent out unused parking spaces and break-even on the proposition.  Instead, that cost gets passed through to the renter – both the cost of the space, as well as the opportunity cost of not building more housing.

The other thing to remember from this is that all of those options for how to park a building might not be allowed.  Tuck-under parking might make sense (get a few spaces at a reasonable cost), but if the zoning code requires more than 0.25 spaces per unit (as it does in Downtown Brooklyn), that method would not be allowed by the zoning code.  Podium parking is also reasonable, but that means you’re devoting the entire first floor to parking – meaning you can’t use it for housing units or retail or any of the other ground-floor uses that make for vibrant streetscapes.

Framing the issue. One other page on Portland’s website does a nice job of framing the issue of zoning code reform for on-site parking requirements.  Instead of talk about reducing on-site parking requirements, we’re talking about places where parking is allowed, but not required.  Soldiers on the automotive side of the “war on cars” (a phrase worthy of the scare quotes) will frequently frame this as removing parking.  This kind of language is both more accurate about potential changes and less inflammatory in skirmishes of this “war.”

More on-street parking isn’t always a problem. One of the fears of these parking-free developments is that not all of those residents will be car-free.  The Portland study shows this to be true – but it also shows that this isn’t really a problem.  Even at the peak utilization of on-street spaces surrounding these new parking-free buildings, 25% of the spaces are still available (page 2 of this document), meaning that there shouldn’t be a problem for residents in finding an on-street space.

Even if on-street parking isn’t actually a problem yet in Portland (no matter how it is perceived), that can always change.  When demand for that parking exceeds the supply, then you turn to parking management.

Managing on-street parking.  If we’ve established that off-street parking requirements increase the cost of housing, and we know that not all residents of a parking-less building will also be car-less, then management of scarce on-street parking will be critical. The Portland Transport blog points to a proposal in Portland that has a nice structure.

The proposal would divide part of the city into essentially three kinds of areas:

  • Commercial areas: all on-street parking is metered.  Anyone may park, but all must pay.
  • Residential areas: residents (with permits) are prioritized, non-residents can park for free, but must obey time limits (similar to DC”s current RPP framework).
  • Bordering areas: on streets adjacent to commercial areas, all spaces are metered but those with residential permits do not need to pay the meters.

Now, the devil is always in the details for things like permit zone sizes, cost of the permits, meter rates, etc.  However, the basic structure does a nice job of shifting the emphasis on what kind of parking should be prioritized in certain areas.

Beyond management. One benefit of allowing more parking-free development would be to increase density in the area, thereby supporting more transit service and key destinations within walking distance.  The more parking-free units there are, the easier it gets for residents to live car-free.  Each of these represents a bit of the virtuous cycle.

DC height limit trade-offs, part 2

DC skyline. CC image from James Calder

Continuing on the discussion of DC’s height limit (and potential changes to it), I wanted to take note of a few more articles on the subject.  George Mason law professor David Schleicher (he of land-use law and procedure fame) asks height limit proponents six basic questions, all of which more or less ask proponents to weigh the trade-offs – or explain why they think the trade-offs do not exist. The six questions:

  1. Do you believe supply is important in determining prices in housing and office markets?
  2. Why do you think development should be spread out?
  3. What effect do you think limiting heights has on agglomeration, including the depth of local markets and information spillovers?
  4. Why do you think D.C. will grow without going up?
  5. Do you think D.C. would instantly become as tall as New York upon repeal?
  6. How much is the D.C. aesthetic worth?

All good questions. So much of planning work is about discussing these trade-offs; an honest discussion of the costs is a prerequisite.

One comment on numbers 5 and 6: DC can indeed go taller while still maintaining the aesthetic of a ‘flat’ skyline, if that is something of value to residents (and therefore worth the cost).  The height limit’s maximum and the flat nature of DC’s skyline are two separate things; if DC’s height limit were set at 200′, we could expect buildings to eventually fill that envelope with numerous buildings up against that limit, rather than form the wedding cake shape of many other American skylines.

Indeed, if that flat-ness is what we value, then we shouldn’t fear adjusting the heights upward – opportunities to shape the city will still exist.

I also wanted to highlight a comment in Kaid Benfield’s original Atlantic Cities piece from ArtR:

1) at current demand for jobs and housing DC has at least a 30 year supply of land to add over 200,000 more jobs and 169,000 people without changes to zoning or the height limit (DC Office of Planning).

I don’t doubt that this is true, but the question of how much land is available gets back to the old real estate cliche of location, location, location.

2) Density through high rise steel and concrete construction will not increase housing affordability. Hard costs alone are over $200/sf with soft cost, land and profit you are well over $400/sf and with even minimal parking you are over $500/sf, thats $500,000 for a small two bedroom. To the extent high-rises syphon off high-income households that might stabilize less costly forms of housing but I am skeptical.

Art is making two points: one about costs, and one about filtering within the market.  In terms of costs, Art is absolutely right – relaxing the height limit will not magically lower construction costs. However, couple that reform with others (such as the aforementioned reduction in required off-street parking) as well as efforts to speed approvals and reduce the lead time required for building and we’re on to something (all potentially positive outcomes of DC’s zoning code review).

The point about filtering is trickier.  Certainly, in the abstract, adding more supply should relieve pressure on older housing units to filter up to more expensive submarkets, but the key phrase in all such abstractions is “all else being equal.”  All else is clearly not equal, and I can’t blame someone for skepticism on the ability for upzoning to make this happen – particularly when such changes to the zoning code happen on an ad-hoc, case-by-case basis.

3) There is a difference between capacity and supply. Raising the height limit may increase capacity but it does nothing for supply. Supply is a function of developers meeting demand and development stops the instant prices stop rising.

While this point is also true, the nature of the equilibrium depends on the other factors influencing cost.  For example, take the examples from Portland, where the elimination of on-site parking requirements allows some development to pencil out a lower price point.

There’s also a point to be made here about location.  If our goal is to add supply, the market might be able to support a lot more supply in more desirable locations.  However, if most of the District’s developable capacity (in point 1 above) is not in those locations, then it will take something else to turn that capacity into new supply.

4) There is nothing to suggest that height alone will increase demand. In fact, too much capacity can increase uncertainty because you never sure how much your competitor can absorb. Denver learned this when they down zoned neighborhoods and they took off.

I hope no one takes away the idea that changing the height limit alone will lead to some magical change in DC’s built environment. Given the fact that zoning is usually an even greater constraint (and given the procedural challenges it can impose), it shouldn’t be seen as a panacea.

Height limit trade-offs

The Cairo. CC image from NCinDC.

Following up on some of the trade-offs mentioned at the end of the previous post on DC’s height act.

In the discussion of Kaid Benfield’s piece supporting DC’s height limit, several comments are worth highlighting. First, Payton Chung notes the need to discuss more than just supply, but to also realize the strength of the demand for living in DC:

I think that a splendid city could be built within the current Height Act, or a revised one, or perhaps even none at all. However, I’ll raise a few counter-factuals, recognizing that I also have not gotten around to writing more extensively about the topic:

1. The growth projections for this region are staggering: +874,394 households and +1,625,205 jobs from 2010-2040. Yet your (and my) preferred strategy of retrofitting mid-rise corridors has a limited upside. Toronto’s Avenues plan, which promotes redeveloping its extensive streetcar commercial strips with a 1:1 street enclosure ratio (building height=street width), only projects an additional 2,000 residents (=1,000 units) per mile of redeveloped “avenue” frontage. Given the District’s small footprint, that’s not going to be enough to absorb very many new residents, much less to increase the city’s housing stock by enough to improve housing affordability.

2. As you well know, a huge difference between Washington and the world’s great mid-rise cities (not just the European capitals, but also cities like Buenos Aires and Kyoto) is that Washington’s mid-rises peter out into single-family houses just one or two miles from the core, while those cities have multifamily-density housing stretching clear to the city limits. This brings me to your point about creativity: what high-rise downtowns do is to concentrate high-value uses within a small area instead of letting it spill out into neighborhoods. High-value office, hotel, and retail uses have priced out most of the creativity in Dupont Circle, Woodley Park, Georgetown, Mount Vernon Square, etc.

Toronto’s Avenues planning study can be found here, and the report’s executive summary is here.  This kind of development is excellent infill and definitely worth pursuing for many cities (not just those with height constraints like DC).  Still, the constraints are real and the opportunity for this kind of infill is limited, however promising it may be.

On Twitter, Neal Lamontagne takes note of the positive abilities of regulations to shape urban development, and the need to balance against their costs:

 [link] @ryanavent Agree, but – limits also linked to + land values. Still, not only economic but also design arguments. Better to shape than squish

Another comment from Payton, making note of the trade-offs in accommodating growth in other areas of the city:

In theory, it should be possible to significantly increase population and jobs within the District and not raise the existing heights. However, the city isn’t exactly littered with vacant lots; such increases would require a lot of demolition, and a lot of density within existing single-family neighborhoods.

Household sizes are *dramatically* smaller than they were: even though the city’s population dropped by 184,000 over the past 60 years, the number of housing units increased by 70,000. Much of that change came from carving up single-family houses into apartments, which is now much more controversial than it used to be.

Under the new Sustainable DC Vision, the city will need over 100,000 new housing units over just the next 20 years. Accommodating more households within the more location-efficient city will, as you know, reduce the region’s ecological footprint. But I genuinely wonder where these units can go: as I mentioned, due to the city’s small size there’s only 3-4 miles of redevelopable land along key arterials like Georgia, Rhode Island, and East Capitol — I’d add some in Upper NW, but you and I both know that’s highly unlikely — and those are only sufficient to address 10% of the total housing demand.

The real reason why Vancouver went whole hog for downtown skyscrapers was not about views, not about impressing people; it was about accommodating dramatic population growth while leaving its single-family neighborhoods mostly untouched, after a citizen revolt over “secondary suites” (accessory units). I know that my neighborhood is (mostly) ready for a few thousand more, perhaps even several thousand more, but is yours?

The point about feasibility is important.  It just might be easier to go to Congress to change the height limit than it would be to fight a million NIMBY battles in established neighborhoods.  There’s a case to be made for more of that type of development to be allowed by-right, but that too represents a big change.

Some of the trade-offs will involve resolving tensions within the urbanist community.  On Twitter, in response to Ryan Avent’s frustrations, Yoni Appelbaum notes:

[link] @ryanavent First-wave urbanism was fundamentally nostalgic. Redevelopment was the threat, and revival the solution.

[link] @ryanavent It’s less an allergy to empiricism than an exposure of the simmering tension between that nostalgia and more progressive visions.

Payton again, asking rhetorically where this mid-rise development will go:

Again to the last two commenters: how do you propose to add mid-rise density without demolishing huge swathes of low-rise buildings, either in the District or Arlington? Already, rowhouse neighborhoods like Chinatown, Foggy Bottom, Southwest/L’Enfant Plaza, the West End, and now Navy Yard and NoMa (particularly its eastern flank) have been sacrificed to extend the medium-rise downtown. Facadectomies are the only way that we have to remind ourselves that these were indeed low-rise at one point in time. Which neighborhoods should be demolished next for the growing downtown?

@tassojunior: we live in small enough apartments already — we have to, what with a median sales price of almost $500/square foot!

Payton, (again!), this time in a thread at Greater Greater Washington:

The problem is not with mid-rise densities, it’s with low-rise densities. I would be happy, perhaps even elated, to see mid-rise densities spread across a wide swathe of Washington, D.C., but I know that many others would not. Indeed, they, including many of Kaid’s neighbors in Ward 3, are already in open revolt, with dire consequences for the city, region, and planet.

You can’t squeeze a fast-growing balloon on the sides (protecting low-density neighborhoods) and the top (height limits) forever.

Bold is mine, and it’s spot on.

 

On density and design tradeoffs

Bethesda Row - note that you don't even see how tall the buildings are - CC image from faceless b

Kaid Benfield’s excellent blog had a post last week on the need for better urban design and management of the public realm in our new, dense infill development. And while I certainly agree with the need for better urban design, I take issue with Kaid’s implication of an explicit trade-off between density and design – that is, the more density you get, the less human-scaled the street will feel as if this were some correlation of a natural law.

Kaid’s post shows several comparison photographs taken from Google streetview, many from the DC area.  What’s missing is an actual accounting for the density embodied in those pictures (such as the visual survey posted here). Additionally, some of the photos Kaid compares are not similar photos – one example involves a view down the axis of a street, while the other is a view of a building’s first floor and the accompanying sidewalk.

For me, it’s a completely different feel.  The second development, part of Bethesda, Maryland’s terrific Bethesda Row area, is not just more inviting but also a bit smaller in scale, at five or six stories tops.  But that’s part of it, in my opinion.  To increase density enough to make a difference, we don’t always need to maximize it.  Much of the time a moderate amount of human-scaled urbanism will be far more appropriate than a high-rise.  This isn’t, or shouldn’t be, just about calculations of units per acre or square footage.  It’s also about what feels right to people.

The sentiment that “we don’t always need to maximize” density implies a tradeoff between human-scaled design and density that I don’t think is absolute.  To a great degree, the influence of design – at the street level in particular – is the key element of a human scale.  In the comments, Payton (assuming this is from Payton Chung) adds this:

I’d agree that it’s almost all about design. The low- and mid-rise floors are most important, to be sure, since humans’ peripheral vision is weakest when looking up. However, there are plenty of historic skyscraper districts that maintain a great sense of place and small scale at the street level (Broadway in Los Angeles is a thrill to walk down), and even some which maintain good sunlight at street level (just was at Rockefeller Center for the first time in a while and reminded of that crucial detail).

Encouraging both smaller parcel sizes — for exactly that granularity, and to ensure greater diversity — and mid-rise heights both ask huge concessions from our current bigger-is-better development paradigm. Of course a developer will build out to whatever envelope the regulations will allow to recoup their costs, will charge high initial rents that only the most reliably profitable (i.e., bland) retailers can afford, and often won’t spend a premium on the sort of pedestrian-scale details that really create a great sidewalk environment. Yet other factors also result in these squat, boring buildings. Occupants will pay a premium for “ground-related” space or for high-rise space with a view, but not for the mid-rise floors. (Compare that to the 18th and 19th centuries, when the 2nd floor commanded the highest rent as it were above street dust but not a long walk up.) High-rise life safety and structural requirements make a 6-story building almost as expensive as a 12-story building. Requirements for exit stairs (like restricting scissor stairs), and tenants’ desire for reconfigurable spaces, both fatten floorplates. Municipalities set build-to lines for bases (correct) and, fearful of oddly height-obsessed NIMBYs, set unrealistically low height limits.

For things like sunlight at street level, the more important considerations would be the orientation of buildings on the site and the setbacks rather than absolute height – issues of design of a different sort than the street level scale.