For over twenty years, the Freeway drive time system has been an integral component in many of the leading site analytics platforms. Recently, we introduced the new Freeway Global system that expands analysis to the remotest parts of the planet. For those familiar with Freeway in the United States and Canada, you were not forgotten! The new underlying engine has two main features of interest to both new and long-time users.
In years past, we relied primarily on the Census Bureau’s TIGER files, which have always been excellent quality and have been well maintained. But the TIGER files suffered from two primary limitations. First, they included only public thoroughfares and thus excluded private streets, which often occur in large shopping malls, industrial parks, and even some large residential communities. Second, because these files were primarily intended for use in delineating census blocks, there was little differentiation between road types. Most of the road type differentiation was on the basis of whether a road was a named highway at the state or federal level.
By switching to the Open Street Map (OSM) files, we were not only able to ‘go global’, but we were also able to add several road classifications which greatly improve polygon definition. First, we added the OSM “service road” classification, which added thousands of private road segments. This means that more locations, especially at shopping centers, are directly attached to the network, resulting in fewer estimation errors and fewer cases where we are unable to even generate a polygon. Second, and equally important, the OSM classification gives us a much improved ability to differentiate between road types because the classification is functional rather than administrative. This functional classification allows us to easily distinguish between roads of different speeds and capacities by splitting the arterial class into major arterial and minor arterial. Speeds can be set for six different link types in the new global model –
- Track / Unimproved
- Service and private roads
- Minor Arterial
- Major Arterial
- Freeway / Expressway
Freeway continues to support urban and non-urban speed settings, so you can easily distinguish between urban and rural traffic conditions. The urban/non-urban is applied seamlessly within each of the resolutions of the system.
The example above, from Minneapolis, shows the benefit of layer differentiation – as five of the six classifications are present. In older versions, the service roads within the Southdale Shopping Center would not be present, as they are private roads. West 66th Street (yellow, running east-west) is classified as a Major Arterial, while West 69th street (white, south of the shopping center) is a Minor Arterial road, and in previous versions, both would have been classified as Arterial.