The zero-sum future - Page 2

We can switch from cars to bikes, now. Or we can leave our kids a climate-change disaster


In fact, a lot of European cities are less dense than San Francisco — and have far fewer drivers. Even in California, the city of Davis is famous for its bike culture; "In Davis," Henderson said, "There are all these children riding their bikes to school."



One of the most profound changes San Francisco is going to have to make involves coming to terms with the immense amount of scarce space that's devoted to cars. Parking spaces may not seem that big — but when you combine the 300-square-foot typical space (larger than many bedrooms and offices) with the space needed for getting into and out of that space, it adds up.

"Parking for 130 cars amounts to about an acre, and the aggregate of all non-residential off-street parking is estimated to be equal in area to several New England states."

Cars need more than a home parking space — they need someplace to park when they're used. So in a city like San Francisco that has more than 350,000 cars, a vast amount of urban land must be devoted to parking. In fact, Henderson estimates that parking space in San Francisco amounts to about 79.4 million square feet — or about 79,400 two-bedroom apartments. Off-street parking alone takes up space that could house 67,000 two-bedroom units.

And it's hella expensive. Building parking adds as much as 20 percent to the cost of a housing unit. He cites studies showing that 20 percent more San Franciscans could afford to buy a condo unit if it didn't include parking.

But the city still mandates off-street parking for all new residential construction — and while activists have managed to get the amount reduced from a minimum of one parking space per unit to a maximum of around eight spaces per 10 units, that's still a whole lot of parking.

And if San Francisco is expected to absorb 90,000 more housing units, under current rules that's 72,000 more cars — which means a demand for 72,000 more parking spaces near offices, shopping districts, and parks. Crazy.

So how do you get Americans, even San Franciscans, to give up what Henderson calls the "sense of entitlement that we can speed across town in a private car?" Some of it requires the classic planning measures of discouraging or banning parking in new development (AT&T Park works quite well as a facility that is primarily accessed by foot and transit). Some of it means putting in the resources to improve public transit.

And a lot of it involves shifting transportation modes to walking and bicycles.

San Francisco has had significant success increasing the use of bikes in the past few years. But there are limits to what you can do by tinkering around the edges, with a few more bike lanes here and there.

There are, for example, the hills. And there's grocery shopping for a family. Those things need bigger shifts in the use of urban space.

San Francisco's street grid, for example, sends travelers straight up some nearly impossible inclines. Young, healthy people in great physical condition can ride bikes up those hills, but children and older people simply can't.

Henderson suggests that the city could install lifts in some areas, but there's another, more radical (but less energy-intensive) solution: Reroute the grid.

If city streets wound around the sides of hills, instead of heading straight up, walking and biking would be far easier. That would involve major changes, particularly since there's housing in the way of any real route changes — but in the long term, that sort of concept should, at least, be on the table.

Bikes with cargo trailers make a lot of sense for shopping, Henderson told me — and once big supermarkets get rid of all that parking, the price of food will come down.