The street hierarchy

"She's got legs / She knows how to use them."


Walking in Phoenix is an act of shame. You don't walk here because you reject car culture and all its dirty geopolitical and environmental implications. You walk because you can't afford not to.

Everyone who sees you using the sidewalk knows this  -- drivers stopped at the light, folks cutting you off in the crosswalk, fellow passengers on the bus. So you avert your eyes, keep your head down, try to ignore the drivers lined up beside you in rush hour traffic. A few proud contrarians can hold their heads up and strut in the face of social judgment. Maybe they've saved half the money for a used Kia Rio and know that soon, with enough overtime at Costco and no more library fines for late DVDs, the privilege of sitting idle on congested surface roads in 100 degree heat will be theirs. Me? I walk fast, and carry extra AA batteries for my Walkman.

I grew up here, learned to drive here, got my first car and first tickets, caused my first accidents and visited my first drive-in theater with an indifferent date here. It was in Phoenix that a car first hit me; nothing major, just a bent BMX wheel and bloody shin. Ironically, life in the desert introduced me to hiking, but it was Phoenix that psychologically transformed ordinary walking into an unavoidable chore.

I harbor no resentments, not even against Henry Ford. The far-reaching effects of Henry's machine are well documented: Cars encourage cities to spread out, not up; sprawling metroplexes contribute to American obesity; by fracturing habitat, roads reduce biodiversity; and the ensuing culture of convenience births such urban inanities as prescription pickup windows and drive-thru postal drop boxes. But what most amazes me is the way the car has alienated urbanites  -- especially Phoenicians  -- from humanity's oldest transportation technology: our legs.

In their song "Walking in L.A," the New Wave band Missing Persons could just as easily have been singing about Phoenix. Singer Dale Bozzio spends her verses trying to figure out why she saw someone on the street. Was it a jogger? she wonders. A homeless man, or someone who just ran out of gas? "One thing's for sure," she sings, that guy "isn't starring in the movies."

'Cause he's walkin' in L.A.

Walkin' in L.A., nobody walks in L.A.

It's unsettling to sing along to lines like "You won't see a kid walking home from school." But what Bozzio brilliantly observed in 1982 was simply the fallout of a virulent urban design system called "the street hierarchy."

Popularized by German urban planner Ludwig Hilberseimer, the street hierarchy is a technique for separating high-speed through traffic from residential areas. Designers based entire "instant cities" like Panorama City and Lakewood, Calif., on the concept, and it has remained the standard model of suburban construction since the 1960s. The hierarchy eliminates straight-line connections between major roads by embedding residences within blocks of smaller curving roads and cul-de-sacs, with limited points of entry. This restricts through traffic to the arterial, boundary roads  -- those roads outside quiet blocks  -- and nestles local traffic and pedestrians inside the neighborhood. Unfortunately, the hierarchy kills the linear connectivity of the old-fashioned grid; that, coupled with suburban developments' use of walls to dampen noise and create privacy, creates a longer, more circuitous route for pedestrians hoping to walk to the coffee shop. There are sidewalks still, usually leading to market. But, as New Urbanist writers like James Kunstler (The Geography of Nowhere) and Andres Duany (Suburban Nation) observe, even though that market may sit a quarter mile from home as the pigeon flies, the drainage ditches, cul-de-sacs and walls in between turn it into a mile-plus walk.

We Phoenicians became car-dependent because of space. Desert is cheap, largely unloved, and there's lots of it. In defiance of water's natural distribution, desert cities like Phoenix and El Paso expand to fill their edges rather than condense around their middles. Where "high-density" is the battle cry of progressive cities like Boulder, Colo., and Minneapolis, Minn., neither geography nor urban design offer sufficient pressure to encourage dense, inward growth in the Sunbelt. Accordingly, driving in Phoenix has become part of its residents' default settings. When it's hot here, you sweat; when you need to go somewhere, you drive. It's only when you move or vacation elsewhere  -- San Francisco, say, or Manhattan  -- that you realize there are other ways to navigate a city. I received my reprogramming in Portland, Ore.