Flood Hazards to Pierce County Transit Routes
An analysis on the potential impacts of a severe flooding event on the public transit routes in Pierce County, Washington. Green routes are at no or lower risk while yellow, orange, and red routes are progressively more impacted.
Initial Steps
Layers added were: Pierce County base map, public transit routes, and flood hazard zones. After clipping the transit route layer to the Pierce County base map, a dissolve was performed on the routes to group them by route number.
Identifying Intersections
This was followed up by intersecting the transit routes with the flood hazard zones, creating an additional data layer seen here in red.
Calculating Percentage of Impact
From there, the percentage of each route that intersected with flood zones was calculated. This created the basis for the final output based on the green-to-red gradient.
Final Output
This final map allows the viewer to easily see which routes would be most affected by flooding. An inset map with the flood zones was also included. The traditional striped fill symbolizing floods did not export for easy viewing, thus a decision was made to keep it a brighter blue for the finished map.
