GeoPython 2021

Cal ToxTrack: A Web GIS for Pollution Mapping in California
2021-04-23, 21:00–21:30, Track 1

This project focused on the public’s right-to-know about toxic chemical releases in their community by developing a geospatial web application called Cal ToxTrack. Built from scratch using PostgreSQL as a database, GeoDjango as a Python development framework, and Leaflet as a JavaScript framework, it effectively visualizes chemical releases and provides interactive tools to help explore pollution data.


Past chemical emergencies in the United States prompted the initiation of a variety of toxic substance and pollution control programs and regulations, including the Emergency Planning and Community Right-to-Know Act and the Clean Air Act. While these have produced decades-worth of valuable pollution datasets, they are stored on a government website in a collection of CSV tables. This method of accessibility is largely incompatible for public analysis due to the static nature of tables— the need to download them locally and appropriately query them to extract relevant data. For analysis, data is best visualized with dynamic tools and within interactive environments.

This application supports open source software and was developed entirely from the backend database to the front end by relying on publicly-available pollution datasets, PostGIS, GeoDjango, and LeafletJS. With Cal ToxTrack, users can utilize a map and spatiotemporal tools to visualize what chemicals have been released, to what magnitude, and where; practicing their right-to-know.