This guest post was originally published at Denver Urbanism.

The air quality on March 7 this year was funky to say the least. The flat yellowish hue of light made it hard to see as I arrived to my morning meeting in RiNo; it also smelled funny. Later that day we learned about a thermal anomaly that kept the pollution particles down making them harder than usual to ignore. But it’s no secret, particularly to those who live with asthma, that air quality in Denver is worsening. And a big portion of pollution particles that make it hard to breathe come from car exhaust.

Would we be healthier if we drove less? Most likely so. But is it possible in a growing city?

The most effective way to decrease driving is reducing the need. If we lived closer to where we work, learn, and play we wouldn’t have to drive so much. It would also make more sense for us to walk or bike. And public transportation would be more practical if more people lived closer together and closer to where they travel.

Single-Unit zoning in Denver is the most predominant zoning designation in residential neighborhoods in Denver. It keeps us far from our destinations and far from one another, forcing us to drive longer distances. It is the least-efficient form of land use in a city, consuming energy and water at much higher rate than more compact development. It requires more public infrastructure and support services. Single-Unit zoning also consumes land that could otherwise be used for parks and open space.

Denver has very ambitious goals of reducing SOV (Single Occupancy Vehicle) commute from 73% to 50% by year 2030 and reducing greenhouse emissions by 80% by year 2050. These transportation goals cannot be reached without the support of land use. But do we have to become Manhattan to live healthier lives and preserve our open space? Not at all. We just need to relax our zoning code to allow more people to live in existing neighborhoods rich in jobs, services, and amenities.

I’ve been writing about the “missing middle” housing for a while. There are countless benefits of allowing multiple dwelling units in the building forms that traditionally have been reserved for single families. It makes our neighborhoods more inclusive and affordable. It preserves historic character of our communities. In the state where more than 30% of greenhouse emissions come from driving, making our neighborhoods more compact would reduce the need for driving and make our air cleaner. Cleaner air, ability to walk and bike, and access to parks would make Denver a healthier and more sustainable city.