Utah State University in Logan, Utah often has complaints from students and visitors about struggling to find the university's overflow parking lots. In an effort to ease this issue, I strove to use georeferencing and digitizing techniques to make the map easier to understand as well as make it spatially accurate. Once that was complete I took the extra step to create an interactive map of the overflow lots in Google Maps for easy access from their mobile devices.

Using a technique known as georeferencing, I took a digital map of the Utah State University-Logan Campus parking lots that lacked spatial data and laid it over a satellite basemap in order to provide a spatially accurate location for the parking map.

In order to accomplish this, I located Utah State University in Logan, UT on a basemap with known spatial reference (in this case GCS North America 1983). I then overlaid the digital map provided by the university to the best of my ability, trying to get landmarks such as street intersections and building corners as close as possible. This was to make the next step easier.

Using georeferencing in ArcPro, I took control points on the overlaid parking map and connected them to landmarks on the basemap. The control point takes a location on the parking map and "stitches" it to a location on the basemap. It's important to take enough control points at reliable locations (such as street intersections) for the digital map is properly positioned. Ways to check this is by changing the transparency of the overlaid map, use swipe to "unroll" the top map in sections to check accuracy and look at the residual errors of the points, either overall or individual. The larger the residual error the more "off" your map is. The goal is zero, or at least near zero.

After getting the digital map "stitched" onto the basemap with limited error, I began the process of digitizing the overflow lots available at the Logan Campus. Digitizing converts image data into vector data that can then be used as a layer in ArcPro. To accomplish this I traced each of the overflow parking lots as a polygon and put them into a new shapefile layer, simultaneously creating a new feature class. A feature class is a collection of features (in this case overflow parking lots), that share attributes and spatial representation.

I took this new shapefile containing the overflow lots and placed it over a satellite basemap of the campus. The new shapefile contained only outlines of the overflow lots, not the rest of the information provided on the original digital map such as the other parking lots or outlines/names of various buildings. Once I checked that the scale and extent of both maps were the same, I laid a grid over both of them representing longitude and latitude. This serves to show the accuracy of the georeferencing and digitizing efforts.

To create the interactive Google map, I used a geoprocessing tool to convert the shapefile layer containing my overflow parking lots into a KML (keyhole markup language) file, so that Google could read my information. Using Google's "Create New Map" option I was able to import my now KML file of the overflow lots and create a new map. After naming the parking lots in reference to the buildings and roads they were closest to, I made the map shareable so that anyone with the link could utilize the map. The map allows the user the ability to reference their current location with the overflow lots around campus.