TOD can make a difference to long-term sustainability of urban areas

Studies show that transit-oriented development really can make a difference to the long-term sustainability of our urban areas.

“Sustainability” is probably the most common word used in urban planning today. Hundreds of books and articles have been written on it, and the federal government is focusing on it through its grant programs. The recent round of HUD/DOT/EPA sustainability planning grants has given regions such as Seattle, Salt Lake City, and Minneapolis-St. Paul major funding sources for regional sustainable planning. But what does it all mean?

Urban transit and its land-use cousin TOD (transit-oriented development) obviously can play a major role in making our cities more sustainable. It all starts with vehicle miles traveled (VMT). The transportation sector accounts for about one-third of all greenhouse gases emitted in the US, and VMT has been growing almost three times faster than the overall population over the last two decades.

One of the most striking passages from Tom Friedman’s book Hot, Flat, and Crowded is a quote from Nate Lewis of CalTech: “Imagine you are driving in your car and every mile you drive you throw a pound of trash out your window. And everyone else on the freeway in their cars and trucks is doing the exact same thing... Well, that is exactly what we are doing; you just can’t see it. Only what we are throwing out is a pound of CO2 – that’s what goes into the atmosphere, on average, every mile we drive.”

Can TOD – with its emphasis on mixed use, walkable, compact development – make a dent in that trend? Can TOD reduce the number of one-pound bags of trash that are going into our atmosphere with every mile driven?

Now that we have almost 20 years of new developments around transit stations, research shows that TOD can indeed make a difference and can drastically help reduce per-capita VMT, which in turn can reduce greenhouse gases. For example:

• Several studies have shown that compact development – increasing density around transit stations – can reduce per capita VMT by 20 to 40%.
• Other studies found that neighborhoods with a good land use mix – providing acombination of residential, commercial, and retail in a compact environment – can reduce per capita VMT by 5 to 15%.
• Residents of TODs tend to own up to 30% fewer private autos and are up to 10 times more likely to use alternative modes of travel than residents of auto-oriented communities.
• People who live in TODs make up to 50% fewer daily trips than those in typical neighborhoods.

Steer Davies Gleave has helped Sacramento develop its TOD guidelines and are conducting a similar effort in Vancouver, and we are currently working with the City of Longmont, Colorado, in designing the future of its downtown rail station area with the aim of preparing an urban realm plan to guide future development and design.

If we can work with our cities to make transit more accessible, convenient, a part of our daily lives and a well-designed part of our neighborhoods, we can begin to make progress in the battle against VMT – and truly make a difference in the longterm sustainability of our urban areas.