Who would have thought that the hottest topic in planning circles would ever be parking?

For generations, we planned our cities for cars first and people second. Now the tide is turning. Cities across the country are focusing on walking and cycling, on transit-oriented development (TOD), and on figuring out the appropriate place and space for parking.

It’s all tied to generational shift. Millennials simply don’t want to drive like their parents did. As consumers, they gravitate toward computers and smartphones rather than cars and televisions. As commuters, they prefer to take transit, walk or bike. And as households, they face uncertain job prospects, a rising cost of living and a need to cut costs and save money. A car is an obvious place to start: Transportation can cost the typical household $11,813 per year in the Chicago region.

Take downtown Evanston, for example. Within a five-minute walk of the Davis CTA and Metra stations, households in 2010 owned fewer than one car on average. Among Millennials, who make up 58 percent of all  renters in downtown Evanston — in part reflecting the community’s significant Northwestern student population — car ownership was even lower. Four out of every 10 households under the age of 35 owned no car at all.

This raises an important question: When buildings are constructed near transit (TOD), how much parking do they really need?

The Center for Neighborhood Technology (CNT) sought to answer that question in King County, Wash., where it worked to develop an empirically based model of parking requirements. Local researchers went into buildings at 3 a.m. to measure the number of parking spaces that were actually used, and then CNT developed a model that related the number of occupied parking spaces to the population and job density, size of units and distance from transit. CNT found that the number of spaces required through zoning exceeded the demand for spots by 35 percent. CNT’s model will likely become the basis for new King County parking requirements in their building code.

Let’s learn from King County, and modernize our own codes.

One example of smart TOD in Chicago is a 99-unit building at the intersection of Ashland, Division, and Milwaukee that replaced a fast food restaurant and was constructed without a single parking spot. Instead, the developer focused on shared solutions, such as 99 bicycle parking spaces, one car share vehicle, proximity to the CTA Blue Line and three bus lines. It’s even built for our fickle weather: Residents can track the arrival times for all of these transit options in the lobby! Every unit in the building was leased within seven months without any parking spillover to the surrounding neighborhood.

We need more buildings like 1611 W. Division, because right sizing parking is a win/win. It reduces the cost of new buildings for the developers and, in the long term, for renters who ultimately pay the bill.

Empty parking spaces at 3 a.m. won’t do anyone any good.

Editor's note: A version of this appeared in the Chicago Sun-Times at http://chicago.suntimes.com/opinion/7/71/663326/millennials-dont-need-ch...