Geog 337 Final Project

Background:

The goal of this assignment was to create an original project to showcase GIS skills learned  throughout the semester and to present your findings. For my project I choose to perform raster and network analysis to examine detour routes for a road project in Appleton, WI. I choose this for my project because I am interested in a career in planning and wanted to use GIS skills in a similar matter to how I would in my future career

Data Sources: My data sources for this project included the Appleton, Wisconsin GIS team webpage, which included a variety of downloadable datasets relating to information within the city. Also, I consulted the Wisconsin department of transportation webpage for traffic data.

Literature Review: 

There were three articles which were used to generate ideas for this project

• Winters Et Al: This research project was conducted in Vancouver, British Columbia to determine which roads in the city were most conducive to bicycling. This article showcased raster analysis as an adequate way to determine road suitability

•  Patel et al 2015: This paper highlighted a traffic study that was conducted in India in an attempt to quantify traffic congestion levels. The article provided me insight into how zoning can influence traffic congestion

•  Tyler 2007: This article examines which factors make an ideal transportation network. This provided  valuable insight considering network analysis was a large part of my project.

Methods:

The first portion of my project involved using raster analysis to determine which roads would be best to use as detour routes. To begin, I examined the attributes of the road that was under construction within the attribute table of the street centerline shapefile from the Appleton GIS webpage. The attributes I choose included the street type, designation and assigned speed limit. I also took into account car count information from the Wisconsin DOT website.

Once I had identified the attributes to base my selection on, I created a raster for each attribute using the feature to raster tool in Arc GIS software. I then reclassified each raster using a Boolean classification system so that desired attribute values were reclassified with a value of 1 and others were assigned values of 0. For example, I wished to select a road with a speed limit of 30 miles per hour or greater. Roads with speed limits within this range were assigned pixel values of 1 while others were given values of Zero. I then performed map algebra and multiplied the rasters. This resulted in all roads with a value of 1 being overlaid on top of each other, providing a final raster of suitable roads to be used for detours. 

Figure 1
Flow Model illustrating steps for raster analysis.

The second phase of this project involved creating a geometric network of Appleton, Wisconsin's city streets to trace an exact detour route based on the results of the raster analysis. Once I determined the closest suitable road to the road under construction, I was able to edit the path in the network using flags and barriers. The GIS then traced a path following the suggested detour route and helps visualize an exact path around the construction zone.

Figure 2

Geometric Network of Appleton City Streets

Results and further study

The result of this project is an effective method of determining road suitability for detour routes. The final road that I had selected as my detour route has been used in the past as a detour route for other road construction projects. For future study I plan on creating a network dataset for Appleton Streets rather than just a geometric network. This will allow me to incorporate elements such as direction of travel (one way streets). Additionally, a network dataset would allow me to additional elements into my analysis. For example, I could include transit data available from the city of Appleton GIS webpage to determine how road construction may interfere with public bus routes and how they would need to be rerouted accordingly.