David Elbert wrote an interesting piece for Wednesday’s Des Moines Register about a mixed-use developments in the “East Village” area of downtown Des Moines. The article’s main focus is a new project that

will have retail on the ground floor, offices on the second and residential units on the third, fourth and fifth floors.

It’s a combination found in stylish developments from Boston to Seattle. Sort of a 21st-century version of the strip mall, without cars and more compact.

Tenants like the concept because the multiple-use design brings people together.

Developers like it because three profit centers – retail, commercial and residential – spread risk in uncertain times.

These neighborhoods offer a good quality of life for people who want a more urban setting, and are good for developers too.

What Elbert didn’t mention is that compact development is also good for the environment; it can reduce the carbon-dioxide emissions that contribute to global warming.

First, mixed-use developments substantially reduce emissions from cars, because their residents live close to amenities and have alternatives to driving. The “Growing Cooler” report on Smart Growth America’s website explains why:

“Curbing emissions from cars depends on a three-legged stool: improved vehicle efficiency, cleaner fuels, and a reduction in driving,” said lead author Reid Ewing, Research Professor at the National Center for Smart Growth, University of Maryland. “The research shows that one of the best ways to reduce vehicle travel is to build places where people can accomplish more with less driving.”

Depending on several factors, from mix of land uses to pedestrian-friendly design, compact development reduces driving from 20 to 40 percent, and more in some instances, according to the forthcoming book Growing Cooler: The Evidence on Urban Development and Climate Change. Typically, Americans living in compact urban neighborhoods where cars are not the only transportation option drive a third fewer miles than those in automobile-oriented suburbs, the researchers found.

[…]

“Clearly, the development industry has a key role in the search for solutions to offset the impact of climate change,” said ULI Senior Resident Fellow William H. Hudnut, III, former mayor of Indianapolis. “Whether close-in or in suburbs, well-planned communities give residents the option to walk, bike or take transit to nearby shopping, retail and entertainment. Being able to spend less time behind the wheel will benefit our health, our pocketbooks and the environment.”

Implementing the policies recommended in the report would reverse a decades-long trend. Since 1980, the number of miles Americans drive has grown three times faster than population, and almost twice as fast as vehicle registrations. Spread-out development is the key factor in that rate of growth, the research team found.

The findings show that people who move into compact, “green neighborhoods” are making as big a contribution to fighting global warming as those who buy the most efficient hybrid vehicles, but remain in car-dependent areas.

Second, apartments or condominiums in mixed-use buildings like the ones described in Elbert’s piece cost less to heat and cool. If you’ve ever used one of those online tools to calculate your carbon footprint, you know that having a stand-alone house with four exterior walls significantly increases your energy usage.