Walmart’s hard lessons: the “D” Word

We here at SRiQ just can't get enough of Walmart. Sure, they're an easy target, but it's one with hard lessons for Sarasota and how we think about development. There are too many conversations that take place in hushed tones: "Ssshhhh --- traffic." "What ... ssshhh, how many stories?" "Don't say the 'D' word or people will get upset ... sshhhhh."

Well, we are gonna take these on, because we can either talk about hard planning issues or get rolled by 'em. And Walmart just rolled into town. So, let's start with the D word: density.

For those on the urban planning learning curve, density describes the concentration of development. In general, the denser the area, the higher the buildings and bigger the building footprint on each lot. It is how we used to do downtowns out of necessity before cars made distance between buildings less of an issue. And because much of Florida (and Sarasota) was developed after our love affair with the car began, we are mostly a spread-out, low-density kind of place.

Along the way, we got used to low density and developed a reflex to fight higher density. Big buildings bring lots of cars and congestion --- right? Intuition says "yes" --- more people equals more cars. But a whopping heap of evidence is saying "no," and the Ringling Shopping Center Walmart teaches us a lot.

First, a primer on how traffic forecasts for development are made. Traffic forecasts are driven by formulas (or formulae for you fancy SRiQ readers) whipped up by a group called the Institute for Transportation Engineers (www.ite.org). Trip generation forecasts are based on land uses that have their own code and projected trip generation. Some uses --- say, convenience stores --- have higher trip generation rates than others --- say, health clubs.

But these codes are under scrutiny. Most studies that generated the official trip rates were conducted when gas was cheap and in sprawl areas where everyone drives. Applying these codes to in-town locations can overestimate traffic. On the other hand, the engineers for Walmart say the superstore will have less traffic than the Publix that was there, according to the ITE numbers, though this doesn’t sound right for anyone who knows the dead mall that it has been. Neighbors fought higher-density, mixed-use proposals based on traffic, because four-story buildings must produce more traffic than a one-story building --- right?

The Ringling Walmart is going to make us learn and relearn what we know about traffic and urban areas. Conventional wisdom has it that compact development reduces overall traffic, but is worse in the area next to these developments. A new study from Arizona (AZ DOT, "Land Use and Traffic Congestion," 2012) shows that mixed-use, compact development reduces traffic in the immediate area, but under certain conditions. The conditions are (1) the use mix has to be there, (2) the surrounding street connections have to be there and designed to improve walking, and (3) retail is the key component so trips for local errands are short and not in a car.

Growth and development activists in Sarasota won’t likely be swayed. And truth be told, congestion around both Walmarts will depend on multi-modal improvements around the stores, not just the location of bike racks in the parking lot. But the city’s long-favored method of financing infrastructure, the impact fee, is really not a good tool for financing urban improvements --- and the city is broke. Neither Walmart qualifies as high density, but each is surrounded by parcels that could be. The irony is that, in order to reduce traffic, we need to increase density. But that density has to be done well and in the right place.

Let us know in the comments what you think: What does reduce traffic, even as the economy grows?