The 21st Congress for the New Urbanism is going on right now in Salt Lake City. We have three bloggers on hand to tell you about its highlights.

Salt Lake City Mayor Ralph Becker opened CNU 21 on Wednesday by sharing a vision of livability and sustainability in the host city. As Becker noted, comprehensive long-term specific measures continue to reshape not just his city but the entire Salt Lake Valley to make the region more transit-focused. An extensive light rail system stretches from Provo to Ogden with Salt Lake in the middle. Over 100 changes to codes have been undertaken in the past three years alone, allowing for development and implementation of livability improvements such as complete streets, a system of shared pathways, bike lanes, connected corridors and increased recreational access.

And while the mayor’s presentation showed what could be done with a clear vision and a plan in place, it was the evening’s main speaker, author Richard Louv, who gave those in attendance something very pressing to think about.

Louv, who has written eight books including Last Child in the Woods: Saving Our Children from Nature-Deficit Disorder, addressed the growing disconnect between children and the natural world, and what this means for the future. Louv pointed to studies that show how a majority of children in San Diego, his hometown, have never touched seawater, and how others who live in areas such as, say, Salt Lake City have never been to a mountain. He noted that independent play has decreased by an average of nine hours per week and that fewer and fewer children are exploring and playing in nature.

We’ve heard the oft-cited reasons for this: Competition with computers and video games, plus a culture of fear on the part of parents. But another reason, and the one most important for the crowd at hand, is poor neighborhood design that discourages children (and adults) from going outside. As the Centers for Disease Control and Prevention have pointed out, only one in five children live within walking distance of a park or playground.

The consequence for society is that we see more and more children diagnosed with attention deficit disorder, obesity and loss of executive function, or the ability to make decisions for themselves. In fact, we are beginning to see the same diseases in people who lead sedentary lives as we do in those who smoke. Taglines such as “sitting is the new smoking” and “leave no child inside” are becoming popular refrains.

The solution — find a way to get kids outside more often — is clear enough, and there are a number of ways to get there. A growing movement of “family nature clubs” has parents and guardians taking the lead in organizing outdoor events and inviting other families to join. Pediatricians are actually beginning to write “park prescriptions” — one program in Portland, Ore. has doctors and the parks department working together to let families know about recommended resources for outdoor recreation.

As the various assembled planners, architects and urbanists come away from CNU 21, they shouldn’t forget to keep spaces for play and recreation in mind in future plans for their hometowns.

Arnold Weinfeld is the director of strategic initiatives at the Michigan Municipal League.