DIGITIZING IN PLANNING
CMP 6700 - Walking and Biking Planning & Design
Digitizing is the process of converting information into a digital format. In GIS, this means converting geographic data into vector data by tracing the edges of the features. It helps us acquire a better understanding of the land and be able to quickly discern between the uses of it. In planning, digitizing allows for more specificity than simply looking at zoning ordinances. Zoning ordinances are often more large-scale in terms of how they divide up the landscape; digitizing gets the exact use of each and every building. The only drawback of digitizing is that it is done from a top-down perspective. It does not take into account structures that might have multiple different uses depending on what floor is being analyzed.
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​The goal of this project is to use GIS to clearly differentiate the way land is used in a focused area of Salt Lake City. In doing this, the digitized landscape will show the exact way that land is being used. More specifically, it will show how much land area is being devoted solely to automobiles compared to land being used for bike lanes or dedicated walkways.
Process
ArcGIS Pro was used for the digitizing process. The first step was to create a geodatabase and project file for the work to be stored, and then create the feature datasets. A boundary was established in Salt Lake City, one that would encompass all of the downtown area but also extend out into some small neighborhoods to the southeast to analyze land uses in a different part of the city. Once the boundary was established, twelve categories were created to divide the land uses by: bike lanes, business uses, dedicated walkways, educational uses, entertainment uses, governmental buildings, green space, parking lots, religious uses, residential areas, roads, and transit. Elaborating on a few them, bike lanes include bike lanes that are both protected or simply striped on the road. Business uses include things like restaurants and shops or stores. Dedicated walkways are wider paved areas primarily used for the purposes of walking. Time constraints prevented sidewalks from being counted as a dedicated walkway. Green space is more focused on larger areas; front yards of houses are not included in this category. The same concept is applied to parking lots in that driveways in front of houses were not counted as a parking lot. The transit locations were also exclusively transit; only things such as protected train tracks or train stations were counted. Areas on roads that are shared by both transit and roads were counted as roads.
The Digitized Landscape
Business uses clearly dominate the primary downtown area, while things get more residential overall as you move east and southeast. Parking lots dominate almost every block, especially in the interior of the blocks. Green space can be found on the edges of many of the city blocks. Entertainment uses often have the largest chunks of any of the uses, but they are few in number.
Figure 1: The Digitized SLC Landscape
Square Foot Total of Each Land Use
This figure shows the total square footage of each land use category in Salt Lake City. The highest by far in parking lot space. This is followed by residential uses and then business uses and roads closely split the third and fourth highest uses.
Figure 2: Square Footage of Each Land Use
Conclusion
Space in Salt Lake City is drastically skewed towards cars. Parking lots alone make up 25% of the digitized space in Salt Lake City. When roads are added to that figure, 41% of all land are solely for the use of automobiles. When compared with the other land uses for human travel, bike lanes make up 1% of all land used, and transit also makes up 1%. 69% of commuters in Salt Lake City commute to work via car, 6.7% commute via transit, and 2.6% commute via bike. These numbers show that transit is by far the most efficient land use in terms of moving people from one place to another, followed by bike lanes. When nearly half of the space in the city is dedicated to mode of travel, as a planner it is difficult to break away from that. In order to get people out of their cars, it is important to seek more balance in our land uses. The data shows in particular that transit is a very efficient use of space for the volume of people that it moves. As the population continues to grow, it is important to develop these more efficient means of travel in order to avoid daily automobile gridlock in Salt Lake City.
Skills Learned / Used
GIS Analysis
Spatial Data
Project Design