A new study finds there are too many parking spots for Chicago apartments:

A single underground parking space can cost $37,000 or more to build, Smith said. Developers in Chicago are generally required to build one parking space for every apartment unit, which has led to a gap between supply and demand, and a fixed cost that is passed on to renters, he said…

As part of its yearlong study, Smith and two colleagues visited 40 residential parking facilities in the middle of the night last summer to survey occupancy. The properties ran the gamut from affordable to luxury rental apartments in Chicago and suburban Cook County and included some older buildings that predated the parking requirements ordinance. The research team discovered lots of open spaces.

On average, the buildings supplied .61 parking spaces for every unit, but used only .34 spaces per unit. Adjusted for occupancy — vacant apartments that don’t need parking — the lots were about two-thirds full, according to the report…

In the suburbs, where public transit is less accessible and car travel is a way of life, municipalities often require developers to provide more than one parking space per apartment unit. The study found the parking oversupply extends to the suburbs as well.

As Americans drove more – even in cities – local officials tried to keep up by building roads and highways, planning communities around automobiles, and writing regulations that provided plenty of parking. All those giant parking lots outside of big box stores or shopping malls are the result of planning for once-a-year parking needs while the rest of the year those lots sit empty, look ugly, and contribute to water runoff issues.

But, what happens if driving habits change? Or, planning as a field changes from emphasizing cars to greener options? As the article notes, Chicago has changed regulations for new apartment developments near mass transit. This seems like a win-win for developers: they have to devote less space for parking which can then go toward units and this may even drive up the price of the parking they do build because there is a tighter supply. At the same time, I wonder if this appeals to certain urban homeowners – particularly younger residents rather than all those Baby Boomers supposedly moving to cities – and not others.