When you look at the image, you can easily see the intersection of two interstate highways, I-25 and I-40 is the greatest concentration of toxic vehicle pollution in the city.

It’s the kind of graphic information that elected officials and public planners can grasp immediately.

So when planners have information about how much vehicle pollution would go up or down with the addition of a new traffic lane on a road, will they make better decisions? In Albuquerque they soon will have information they can act on.

A new $335,000 grant from the U.S. Environmental Protection Agency to UNM Civil Engineering Assistant Professor Gregory Rowangould will allow him to model how changes in traffic patterns and land use affect greenhouse gas and toxic air pollutant emissions from vehicle use. The three year grant will involve modeling for Albuquerque, New Mexico and Atlanta, Ga.

Rowangould has spent the last several years developing models that calculate air pollution effects from vehicle emissions. This grant will allow him to add information about land use into the mix.

This overlay shows vehicle emissions in Albuquerque. The areas in red show higher emissions near the intersection of I-25 and I-40. Yeallow shos the lower emissions levels along major traffic arterials.
This overlay shows vehicle emissions in Albuquerque. The areas in red show higher emissions near the intersection of I-25 and I-40. Yellow shos the lower emissions levels along major traffic arterials.

He said smart growth strategies, which encourage a greater mix and density of development are currently popular as planners try to find ways to reduce private vehicle use and the pollutants they emit by making it easier for people to walk or ride bikes or use mass transit. It’s why planners and politicians take steps to give people an incentive to move into city centers.

“So while regional emissions are going down, you are potentially placing more people in an area that is relatively more polluted. By shifting new growth from the less developed fringe and suburban areas to urban areas, people may drive less on average but you are also concentrating more vehicle activity into a smaller area so that could affect the amount of toxic vehicle emissions that people are exposed to,” he said.

Rowangould’s research could guide elected leaders and planners in how they think about developing cities to protect the climate and public health. “It’s all about how we reduce greenhouse gas emissions and exposure to toxic vehicle emissions through our transportation plans and our land use plans. We are going to simulate hundreds if not thousands of different development scenarios and see if we can find strategies that advance both of these goals.”

The Mid-Region Council of Governments in Albuquerque has shared data they use to develop transportation models for the region so he can work directly with information in a real life setting. In turn he will share his simulations with planners so local elected officials can plan the future of Albuquerque using the best science available.

Rowangould said, “What we are trying to find are strategies for developing a city that reduces greenhouse gas emissions and that do not increase exposure to toxic vehicle emissions. For example before you encourage people to move downtown, should you build out a transit system first so that new residents are likely to drive less? Or do you wait until more people move downtown when there will be more demand for transit?

If you wait, are downtown residents going to suffer from higher levels of air pollution? There are potentially different ways to phase land-use and transportation strategies to address a variety of goals simultaneously and avoid unintended consequences. What we are going to do is simulate many different land-use and transportation strategies year-by-year through a 30-year time horizon, which no one has ever done before.”

The models could also help sort out whether short-term solutions cause long-term problems. “For example, widening roads and highways reduces emissions when they speed up traffic. Keep cars moving more quickly with fewer stops and that creates fewer pollutants. Over the long run though, that usually results in more driving and more sprawl and therefore more vehicle emissions,” he said.

Short-term strategies may be part of a more durable solution if they are coupled with long-term strategies to discourage urban sprawl, incentivizing infill development and building transit systems to reduce the need for motor vehicles.

Rowangould said, “The main thing is we are thinking about is how to create cities that are healthy to live in from an air quality perspective and that also reduce greenhouse gas emissions from transportation.”