I'm a lazy thinker
Status quo city planning is often based on drama, not data.
Your brain has heard a million times that peanuts are, without a doubt, one of the most dangerous substances known to man, and any good parent would shield their children. The “usual suspect” threat levels to children go something like (1) nuclear explosion, (2) playing outside without supervision, (3) peanuts, (4) bicycling without a helmet, and then a long list of scenarios that are statistically never going to happen.
In reality, driving your kids to the allergist is far more dangerous than the allergy itself. One way to explain this disconnect from reality is the availability heuristic. The Psychology Dictionary defines availability heuristic as “a common quick strategy for making judgments about the likelihood of occurrence.” When you’re presented with a topic, your mind snags the first available and most used information. Accuracy doesn’t matter.
Whether it’s the news of kidnappings or baby Jessicas falling down holes in the ground, the brain gets bombarded with sensational headlines and video clips, so that’s what sticks in your mind. There’s no media blitz about the medical reports that you’re 14 times more likely to perish in the confines of your bathroom than from a shark attack. Bathrooms are boring. So your brain isn’t on alert for slips on wet tubs (falls are common) like it is around ice cream trucks (kidnappings are rare).
Policymakers are just as susceptible to making decisions based on available but incomplete or inaccurate data. Local planning departments, state transportation departments, environmental agencies, automobile safety agencies—they’re all run by decision makers whose minds may or may not be reaching for the best information.
Consider urbanism-related issues that quietly screw things up while everyone shrugs them off.
1. Minimum Parking Requirements. “It took forever to find a parking spot” sticks in the mind, so a government rule mandating a minimum amount of parking for every type of land use seems reasonable. The brain doesn’t know about the economic disaster that looms when cities are rebuilt around car storage.
2. Single-Use Zoning. “They might build a paper mill and a strip club next to an elementary school!” It’s as routine a social media defense of zoning as it is silly. Travel distances grow, car trips increase, and mixed-use neighborhoods decrease.
3. Standard Traffic Analysis. Every state department of transportation has a library of propaganda about how they optimize an efficient transportation system. You visualize cars and trucks seamlessly moving through a network, not realizing the tradeoffs of minimal vehicular delay include the destruction of local economies and public health.
4. Setback Requirements. You wouldn’t want a car to accidentally skip over the curb and crash into a storefront, would you? Of course not. So it doesn’t seem like a big deal that the planning department forces property owners to put their buildings wayyy back from the street.
5. Building Height Restrictions. In any given week, there’s a news story about NIMBYs complaining that tall buildings will block sunlight, viewsheds, etc. It’s one of the regular horrors of property rights, we’re frequently told. Our brains aren’t flooded with stories about how important it is to increase density on busy corridors since transit is so much more efficient for moving large groups of people at the same time.
6. Residential Street Design. One of the deadliest myths in the US is that residential neighborhoods need wide streets to accommodate emergency vehicles. Your mind recalls the fire chief quoted in the news, saying something like “seconds matter, so if someone is broken down in the street, we need room to pass them.” The result, of course, is dangerously wide streets with regular speeding problems.
7. Blocking Adaptive Reuse. Historic preservation stories are some of the most emotional, so it’s easy for the brain to remember them. If there’s a rezoning case in the news where a property owner wants to build housing on that “historic” gravel parking lot, you’re torn because… “I’m not against housing, but can’t you find another site that isn’t historic?”
The availability heuristic latches onto loud, easy-to-recall ideas (traffic jams, quaint history) while the slow-burn damage (sprawl, housing shortages) slips by unnoticed. I’m sure you could come up with dozens more.