How much vehicle traffic should a main street have?

Westmoreland district, Portland. Image: Ashley Brandt

Picture a vibrant neighborhood business district in an American city – one that’s located outside of the downtown area. Or, envision the main street of one of your favorite small towns. Think cafes, restaurants with sidewalk seating, quirky stores, street trees, two- to four-story buildings close to the sidewalk, people strolling about.

Now, what is the car traffic like? Is it busy? Too busy? Not busy enough? Moving too fast? Not moving at all? Or is it just right?

Suburban active mode share: Let's kick it up a notch

We planners get excited about mode share – the proportion of trips taken by different modes of 

transportation such as driving, transit, walking and biking. Mode share is often a source of bragging rights (Portland’s 6% bike commuting mode share is the highest of any major American city) or grounds for shaming (only 2% of Indianapolis commuters ride transit). Why does mode share matter? Because the better job we do with reducing driving (especially driving alone in urban areas), the more progress we make on reducing carbon and particulate emissions, alleviating traffic congestion, reducing transportation costs for people and governments, and leading healthy, active lifestyles.

A woman walks onto a MAX light rail platform in
Washington County, OR. Image: author

News stories about mode share typically boast of various large cities curbing their driving habits and successfully getting people to walk, bike and take transit. And good for them. But how are the suburbs doing? If much of the growth we’re expected to see in the 21st century is to occur in the suburbs of major cities, it is critically important that we plan for different ways of getting around. It’s easy enough for large cities, with their established transit systems, walkable street grids and dense development patterns, to cajole people out of their cars. The suburbs, however, face a tougher climb. Destinations are dispersed. Cul-de-sacs and looping streets thwart convenient walking and biking. Sidewalks, bike lanes and transit service are riddled with holes, if not absent altogether.

But some suburbs offer a respectable array of multi-modal travel options that inspire many of their residents to trade car keys for bike locks or transit passes. A handful of suburban counties actually outperform car-centric city jurisdictions elsewhere in the country (Bergen County, NJ’s transit commuting rate is thrice that of Houston, for example). How do they do it?

When backage becomes frontage and frontage backage

One suburban design flaw discussed far less often than the cul-de-sac or the strip mall is the “backage” road – a road that provides vehicular access to the rear of properties that otherwise have “frontage” along an arterial road. The backage road optimizes vehicular operations on the arterial by limiting access and reducing turning movements. This improves the arterial’s capacity and, some say, its safety. Indeed, this arrangement is much safer than 1950s-era arterials, where a constant barrage of driveway openings create turning conflicts for people driving, walking and cycling.

However, backage roads have unintended consequences. By providing direct property access for vehicles, backage roads have encouraged land uses to “front” them. Front doors, windows and parking for businesses and homes are oriented toward the backage road instead of the arterial. In effect, the backage road has frontage, and the arterial frontage has backage. Zounds!

Why I'm canceling my subscription to The Oregonian tomorrow

The Oregonian newspaper is discontinuing daily delivery starting on Tuesday. Home subscribers will subsequently get three and a half newspapers delivered per week – three “premium” editions on Wednesday, Friday and Sunday, and a thinner one on Saturday. Same price! The remaining three papers will be available at retail locations at marked up prices, or downloadable as a PDF called “My Digital O.” Because everyone loves scrolling around an oversized PDF page on their iPad.

While I have been a print newspaper loyalist for all of my adult life (bucking the trend of most Gen X-ers), The Oregonian has given me no choice but to cancel and do other things with my time. Here are my top ten reasons why:

Connectivity barriers: When is it worth breaking them?

Portland's Reedway Street at the Union
Pacific railroad. Try crossing this! Actually,
don't. Image: author.

Why did the chicken cross the road? You know the rest. But what if that road is a 16-lane freeway, or the busiest railroad in the state? Or, what if it is a natural “road” – a river, gulch, canyon, arroyo, cliff or hillside?  To get to the other side, the chicken would need to somehow avoid dismemberment or drowning. More probable is that our feathered friend would stay on its side of the road, or take a circuitous route that increases the length and time of its trip by a large factor. As such, the chicken may be encouraged to get in its chicken car and drive two miles to a destination that is really just 200 feet away for a more flight-capable bird.

Transportation facilities – linear features intended to provide mobility – sometimes reduce it instead. Much has been written about mid-century freeways severing urban neighborhoods that, due to their disenfranchised minority populations and blighted housing stock, were deemed disposable. And most Americans have heard the expression that someone “grew up on the wrong side of the tracks.” While we have enjoyed the economic benefits of freeways and railroads, they came with a steep social price that we are still paying today.


Sometimes, if a community gets sufficiently annoyed about the gulf separating them from where they want to go, they organize and ask their leaders for a crossing. If they’re lucky, someone listens, finds a few million bucks, and gets it built.

This presents a series of policy questions. When is it worth spending millions to connect two sides of a freeway, railroad or river with a grade-separated crossing? What are the density thresholds or other criteria that make it worthwhile? How far apart should these crossings be spaced in urban, suburban and rural contexts? Should a new crossing be just for people on foot or bike, or should it be a complete street, or even a new interchange? How about just peds, bikes and emergency vehicles? Conversely, when is it okay to say, “No, you people don’t need to get from point A to point B in any sort of direct fashion”?

The answer is usually, “It depends.” But that’s not very helpful. Short of a doctoral thesis project, we can at least take an anecdotal look at how transportation planners have responded to these questions in practice.

The South Could Learn From The South

When one thinks of innovative, sustainable urban planning, the American South doesn’t come to mind. As the story goes, the South’s most significant boom took place after World War II, spurred by the advent of air conditioning and the growth of defense-related industries. We know what forms of development the mid 20th century brought: sprawling, looping subdivisions with homes on oversized lots; seven-lane arterial roads with big box stores and garrish signage; downtown urban renewal schemes with brutalist concrete architecture and dead streets. Really, it was the same stuff being built everywhere else in mid-century America, just more of it, and worse. And with Piggly Wigglys.

Attack of the house clones!

In the spirit of Halloween, I’ll tell you what spooks me. It’s not ghosts, ghouls, goblins, the Frankenstorm, or the prospect of a Romney presidency. No, it’s the outsized neo-traditional house clones that are popping up en masse in many a Portland neighborhood. Like zombies, they rise from the graves of once-affordable properties. What are these strange, deformed creatures of the night, with names like Meriwether, Ainsworth and Montgomery? They are the Renaissance Homes Vintage Collection – new homes with “all the updated charm, built-ins and period details of the Portland homes you’ve come to love.”

Okay, in the scheme of things, a recovering housing market is nothing to be scared of, and I applaud the effort to design homes that attempt to blend into the milieu of older neighborhoods. But I take issue with these offerings from Renaissance for several reasons: