Comparing Discrete Global Grids Versus ZIP Codes for Spatial Analysis in Public Health

Keywords: publichealth,indexing,globalgrid,h3,Uber,GIS,ZIP
Abstract Type: Poster Abstract

Abstract

In 1963, the Zone Improvement Plan, or ZIP code, was implemented by the US Post Office Department (USPOD) to improve mail delivery. Rather than an assigned area, it is a collection of routes. While this system fulfills its role in package delivery, the shape and allocation of these routes and their reliability as a metric for spatial analysis is poorly suited to real world spatial analysis applications. For example, the blood lead levels measured in Flint, Michigan were difficult for geographers to pinpoint since ZIP codes within the city extended into many other townships and cities. This poster will apply Uber’s H3 to analyze water quality data in Flint. H3 is a hexagonal grid system that indexes locations and aggregates point data, initially designed to optimize the allocation of rideshare drivers. We highlight the challenges and opportunities associated with evaluating a public health crisis like the one found in Flint with discrete global grid systems and compare their utility versus the more commonly used ZIP code.