John Holtzclaw, a transportation researcher from the Bay Area of California, has an interesting website that shows the relationships between residential density and driving. It includes photos of different San Francisco neighborhoods and data on their density, fuel use, and air pollution rates. One point: high density doesn’t necessarily mean high rise.
You can also use his calculator to check your own neighborhood’s (projected) fuel consumption. But you’ll have to estimate how many households live on each “residential acre” near you. Residential acres exclude streets, sidewalks, stores, and offices. An acre is about the size of a football field.