Tuesday, December 28, 2010

Why we walk

One of CREC's primary goals is to create tools that help planners assess the pedestrian environment and identify what changes to make in order to allow residents to walk instead of drive.  Fortunately, this is a hot topic these days, and there are a growing number of websites that provide information about how well-suited a given location is for walking.  Taking a spin through a few of these websites is a good way to investigate in more depth what a "walkable" neighborhood means.

Probably the most well-known web-based walkability tool is Walk Score.  According to Walk Score, we walk if there are places nearby to walk to.  The site rates a location on a scale from 0 to 100 based on its proximity to amenities across several different categories, including stores, entertainment districts, banks, schools, and libraries.  Below is a screen shot showing Walk Score's assessment of the area around CREC's headquarters in Berkeley:

Researchers often talk about the "four Ds" of land use--density, diversity of uses, pedestrian design, and access to destinations--that studies have shown to reduce driving, and implicitly, to increase walking.  Of the four Ds, Walk Score addresses access to destinations most directly, but also density and diversity of uses, since presumably more compact and mixed use neighborhoods will have shorter distances between homes and the amenities that Walk Score examines.  Of course, whether you actually visit the destinations that Walk Score looks at is another question--as a lunch spot, Adagia is out of our price range, and Urban Outfitters doesn't quite offer the professorial tweeds favored by researchers--but I generally find it to be a pretty accurate tool regardless, because of the way that amenities cluster together in commercial districts.

Another tool that Walk Score has recently unveiled focuses more narrowly on accessibility.  Its Transit Time Map shows you all the places that you can reach within 45 minutes of a given point by walking and taking transit.  According to this tool, you're more likely to walk if you can get farther without a car.  Since CREC headquarters is a pretty long walk from the Downtown Berkeley BART station, we can only make it a few BART stops in either direction, even if we head out during the evening rush hour, when trains are running most frequently:

Mapnificent is another tool that measures accessibility.  Unlike the Transit Time Map, Mapnificent uses average transit headways and travel times, rather than adjusting your range depending on when you take your journey.  But it makes up for this lack of precision by allowing you to adjust your travel time and other factors, including whether or not you have a bicycle, as well as including some nice rainbow color-coding.  Mapnificent confirms a hypothesis that I've come up with in the course of my commute, which is that I need a bike in order to get from my neighborhood in San Francisco to CREC's offices in under an hour.  Here's my 55-minute travel radius with a bike:

And here's the same radius without a bike:
The one D that these tools leave out is pedestrian design.  As far as the Mapnificent and Walk Score are concerned, it doesn't matter whether there's a wide pedestrian-only path or an interstate highway connecting you and the nearest coffee shop (fortunately in our case it's the former, which helps to prevent accidents on drowsy Monday mornings).  The Walk Score team readily acknowledges this shortcoming, and is working to overcome it, but critics of the tool claim that the lack of consideration for design is a fatal flaw--see the Conservative Planner's post on the topic for a number of examples where Walk Score gives high rankings to neighborhoods in which walking would be tantamount to suicide.  However, the designers of tools like Walk Score and Mapnificent are doing the best they can with the data that is readily available, and currently there's no database of sidewalk conditions or other pedestrian amenities out there--nor is there even a standardized way for cities to collect this data.  This is something that we're working to develop here at CREC.

In the meantime, Walk Score has caught on with real estate agents, who frequently use it to promote properties in pedestrian-friendly neighborhoods, and both the designers of the Transit Time Map and Mapnificent express hopes that their tools can help people locate neighborhoods in which they can live a car-free lifestyle.  More importantly, these tools continue to foster a lot of discussion about the benefits of compact, walkable neighborhoods, which is an important first step in reversing several decades of car-oriented planning.

Wednesday, December 1, 2010

Reaching 2050 Climate Goals II: The Critical Role of VMT

In my previous post, I described the magnitude of the challenge facing California (and all of industrialized society) in meeting the greenhouse gas emissions goals that science and state policy agree are necessary.

A key conclusion of this discussion is the fact that all sectors of the economy must achieve deep reductions, not just one or two. This certainly includes the transportation system, which in California is the largest single source of GHGs (38 percent of the total, according to the California Air Resources Board). Transportation-related emissions, in turn, are a product of three factors:
  • The fuel efficiency of vehicles
  • The carbon content of fuels
  • Vehicle miles traveled (VMT)
Multiplying those three factors yields the total carbon emissions. Therefore, unless the fuel stock for vehicles can be totally decarbonized within 40 years (e.g. perhaps by conversion to an electric vehicles fleet powered entirely by carbon-free renewable energy), there will once again have to be substantial improvements in all three areas in order to bring the transportation sector as a whole into line with an 88 percent per capita emissions reduction relative to today's levels (see previous post for an explanation of how that number is derived).

What does this really mean in practice? Well, if we think of fuel efficiency and carbon content collectively as "carbon efficiency" (or carbon emission per mile), then we see that the carbon efficiency times the VMT must be reduced on the order of 88 percent per capita in forty years. If carbon efficiency were quintupled over that time period through a combination of fuel efficiency gains and decarbonization of fuel stocks, we would still need to reduce VMT by 40 percent per capita relative to today's levels. In other words, we would have to "make do" with 40 percent less personal driving, trucking, business travel and all other uses of motorized vehicles. If carbon efficiency is merely doubled, we would need to reduce the per capita VMT by 76 percent!

Are these changes feasible? Certainly. In fact, there are Americans right now who live well on 76 percent less VMT than their average compatriots. They're the Americans who live in dense urban centers such as New York and San Francisco. Bringing the transportation system into line with our 2050 climate goals means making sure (among other things) that vastly more Americans can live in those kinds of truly dense, mixed-use environments, rather than simply somewhat-more-dense suburban settings (which tend to achieve VMT reductions of only about 20-30 percent).

It can be done -- but modest changes to how we build urban regions won't get us there.

Tuesday, November 30, 2010

BOD (Bicycle-Oriented Development)

I recently heard a presentation form Dr. Billy Fields of the University of New Orleans' Center for Urban and Public Affairs on the Midtown Greenway in Minneapolis, which is a 5.5 mile bike/ped trail along an old rail alignment in South Minneapolis. 
Photo courtesy of the City of Minneapolis
It certainly looks like a great rails-to-trails conversion.  But what really piqued my interest was the trail's BikeCenter, which includes parking spaces, shower facilities, and a repair shop, as well as the headquarters of the Midtown Greenway Coalition.  These are all useful facilities, but even more remarkably, the BikeCenter has no parking spaces nor street level access.  Instead, as you can see in the photos below, it fronts on the trail:
Photo courtesy of Thinking Outside

Photo courtesy of Thinking Outside
Dr. Fields also mentioned that the land use plan for the Greenway Corridor states that buildings adjacent to the Greenway should have adequate setbacks so that they don't block the Greenway's sun--an important consideration given Minneapolis' cold winters (the Greenway is plowed during the winter, so it gets year-round use).

Transportation departments normally have sole domain over bike facilities, so it's exciting to see a city thinking outside of the box, and considering both development opportunities adjacent to these facilities and land use guidelines that keep conditions pleasant for cyclists.  The Greenway provides a good example of the type of holistic thinking that is necessary in order to fully integrate bicycles and other sustainable transportation modes into a community.  Granted, situating a bike shop along a bike path in one of the nation's most bike-friendly cities is a bit of a no-brainer, and given that bikes account for under 10 percent of trips in even the most biketopian cities it's unlikely that we're going to see full-blown cyclo-mall districts popping up any time soon.  Still, Minneapolis' Greenway raises some good questions about land use decisions in areas where a lot of people ride bikes. 

Photo courtesy of BikePortland.org
For instance, if a city is willing to allow businesses to convert a parking space to a bike corral, as in the photo above, shouldn't it also be willing to lower the parking requirements for businesses on the assumption that customers are going to visit by bike rather than on foot?  We're not going to see real change in the way people travel until we start treating bicycles, transit, and feet as primary modes of transportation rather than treating them as an afterthought.  Converting old rail lines and underused space in the right-of-way to sildewalks, lanes, and trails is a necessary first step; now we need to start thinking about how to re-orient our cities around these facilities so that they become thoroughfares for everyday travel.

Monday, November 29, 2010

Reaching 2050 Climate Goals: The Magnitude of the Challenge

As we launch this blog on climate change and resource efficiency in the built environment, it is worth taking a moment at the beginning to reflect upon the "big numbers" of climate change and the goals that have been set out before us. Though it has been said before, it is worth saying again: moderating climate change (it has already begun and can't be prevented entirely) will require epochal transformations in most aspects of our society and economy -- most especially including the built environment.

Consensus has emerged among scientists that the world must limit global temperature increases to 2 degrees Celsius (about 3.6 degrees Fahrenheit) over pre-industrial levels (not today's levels) to avoid the worst of the possible consequences of climate change. Indeed, at the Copenhagen conference last year, President Obama and numerous other world leaders committed their nations to achieving this goal, even in the absence of any enforceable treaty mechanism to achieve it.

Numerous research and policy efforts, including the Intergovernmental Panel on Climate Change (IPCC) have concluded that this will require cutting global greenhouse gas emissions 60 to 80 percent below 1990 levels by 2050. California, alone among American states so far, has accepted this challenge in the form of Executive Order S-3-05, which sets a target of an 80 percent reduction below 1990 levels by 2050. (The state's more heralded climate law, AB32, requires the state only to return to 1990 levels by 2020, then establishes a cap-and-trade mechanism to achieve the deeper reductions in later decades).

That 80 percent number is even more daunting than it looks, for four reasons:

1. An absolute emissions level that is 80 percent below 1990 levels by 2050 is actually more like 88 percent per capita below today's levels in California, which is perhaps the more relevant figure for policy making. That is because California's emissions levels have grown another 10 percent since 1990 (according to the EPA), and because the state's population is expected to grown by 62 percent between now and 2050 (according to the California Department of Finance).

2. Emissions cuts this deep mean that all major sectors of the economy must achieve approximately that much reduction -- there just isn't enough wiggle room for tradeoffs between sectors. According to the AB 32 Scoping Plan released by the California Air Resources Board, transportation generates about 38 percent of the state's GHG emissions, electricity about 23 percent, industry about 20 percent, and commercial and residential activities about 10 percent (with the remaining 9 percent classified as 'other').

For the sake of illustration, let us suppose that the transportation sector is able to achieve "only" a 75 percent per-capita reduction by 2050, still an arduous political and technological challenge. That would mean that all other sectors -- including all buildings, industry, commercial activity and agriculture -- would have to achieve about a 96 percent reduction by 2050 for the economy to meet the overall 88 percent per capita reduction target. Thus, even a "miracle" breakthrough in one area (say, complete decarbonization of the electricity system) would not relieve other sectors of the economy from the need to achieve profound changes.

3. All of this must occur in just 40 years. That is very little time in the planning world. In the state of California, single mega-projects such as the Bay Bridge retrofit now take nearly that long from conception to completion.

4. On top of all that, there is a large embedded infrastructure problem that must be overcome. Efficiency experts have long realized that most consumers will not buy a new water heater (or refrigerator, stove, etc) until the old one wears out, even if something significantly more efficient is already on the market. The same is true for buildings, roads, and infrastructure, except that these are designed to last for even longer, several decades at a minimum. Why would society replace these paid-for assets with something new before they wear out? Most likely, we won't, or simply won't be able to afford to. That means that we will be living with at least portions of our current energy-intensive landscape for a long time to come.

I'll have more to say about the implications of this monumental challenge for transportation and land use planning in future posts.

Saturday, November 27, 2010

Climate action: what counts, and how cities count it

Over the past decade, cities have been taking the lead in creating policies to fight climate change; conducting inventories of local greenhouse gas emissions, setting goals to reduce emissions, and identifying a set of actions to meet these goals. I've posted greenhouse gas inventories conducted by, respectively, the City of Chicago, the City of Berkeley, and Portland Metro, the regional government for the Portland, OR metro area, below. Take a look at them. Here's Chicago:

And Portland Metro:

Why the differences? Are Chicago's buildings older, or its winters colder? Do people in Berkeley drive more? Do residents of the Portland area buy a lot of goods from halfway around the world? For that matter, do residents of Berkeley and Chicago buy any goods or food that contribute greenhouse gas emissions to the environment?

Figuring out how much a given activity contributes to climate change is a challenging task. But figuring out how much control a local government has over the activities that take place within its jurisdiction--and therefore which categories of greenhouse gas emissions a government should take into account, as well as how effective the different options that are available to planners and policy makers might be in reducing these emissions--is even trickier. When cities create climate policy, they're thinking not only about what's technically effective, but also what's politically feasible.

The differences in the above graphs speak to this fact. Some are technical in nature. For example, electricity in Berkeley and Portland, both of which are located in areas with abundant hydroelectric resources, is relatively clean compared to Chicago's electricity, and Chicago's hot, humid summers and chilly winters mean that residents burn a lot more energy keeping their homes comfortable than in the other two cities, both of which are relatively mild. Both factors may help to account for the large percentage of Chicago's greenhouse gas emissions attributable to "buildings and other energy uses." But politics may also be a factor; the City of Chicago's leverage over building codes and standards give it more direct control over these emissions, and the high-profile green roof atop city hall, constructed in 2001, may have also helped raise awareness of building energy use among citizens.

Meanwhile, according to Portland Metro's count, greenhouse gas emissions due to transportation are about on par with those due to electricity use. But this isn't because Portland area residents drive more: not only does electricity use contributes a smaller share of Portland's GHG emissions because electricity there is cleaner, but as a regional agency, Metro also accounts for longer commutes in suburban areas, while Chicago just examines the transportation emissions of urban residents who drive relatively little. As for the nearly 50 percent of Portland's emissions that come from goods and food consumption, counting such emissions is a rapidly-evolving science, and Portland Metro conducted its inventory much more recently than Berkeley or Chicago. Furthermore, since Metro oversees recycling programs for the entire Portland region, and because the region has a high number of "green consumers" concerned about the environmental impact of their choices, Metro may be more likely to perceive itself as having both the authority and the political advantage to address this category of emissions.

A lot of climate policy focuses more on technological shifts more than the types of changes that the cities above are trying to spur. Historically, our environmental protection policies have leaned heavily on technology, and greenhouse gas reductions are easier to quantify when you don't have to worry about unpredictable things like human behavior. This is part of the reason that SB 375's regional transportation-sector greenhouse gas reduction targets, which call for regional agencies to channel transportation funding toward projects that reduce driving, contribute under three percent of the progress toward California's 2020 reduction goals, according to the Air and Resources Board's AB 32 Scoping Plan. But just because the effect of community design on greenhouse gas emissions is difficult to quantify doesn't mean that it's not important. In fact, I'd argue that community-level climate action is even more important, because people have such a deep tie to the places that they live, so creating greener cities has an educational value that extends far beyond the actual greenhouse gas reductions. Witness Chicago, which since announcing its Green Building Agenda in 2004 has twice hosted the US Green Building Council's Greenbuild Expo, inspiring politicians and builders all over the country.

This is part of the reason that we're doing what we're doing here at CREC--to help cities better understand how to quantify the greenhouse gas reductions and environmental benefits of the decisions that they make, so that they can pursue the project and policies that count the most.