Zoning Out: Collecting and Mapping Data from 100+ Local Planning Departments
PolicyMap is an online GIS for government, commercial, non-profit and academic users to access data about communities. We're currently creating a dataset of nationwide municipal zoning; city by city, zone by zone, and parcel by parcel. Why? Understanding zoning is a key tool urban planning nerds use to understand local real estate development and the built environment. Zoning is one of many administrative data sources that is managed at a municipal level, where local laws govern the definitions of zoning codes. Additionally, this data is challenging to work with because it changes often, sometimes on a daily basis.
In this presentation, I'll focus on our process behind collecting and using local zoning data for PolicyMap, but the experience I'll share can be applied to aggregating or standardizing multiple data sources in any domain. The talk will focus primarily on two aspects: data collection and procedural processing.
Data Collection: Not all data posted on the Internet is open data; in this project, we've blended many different data sources, each with different attribution requirements and limitations. This presentation will cover our data collection process, specifically highlighting the benefits of collecting detailed metadata from day one. I'll discuss where we've struggled and succeeded in data collection, obtaining permissions, and keeping things organized along the way.
Procedural Processing: We've created a partially automated process using relational databases across multiple environments to get the data from hundreds of messy shapefiles into our interactive mapping platform for all to see and use in one place. I'll give an overview of our process, discussing how we're able to standardize the data, create aggregate indicators, and ultimately, how our mapping tools allow users to blend zoning with demographic and socioeconomic data. I will show off the places where this process works seamlessly, as well as some of the more painstaking data entry components we’re stuck with (Thank you, interns!).
As a bonus, attendees will learn a bit about zoning data as it relates to urban planning and policy decisions. Topics for discussion will include municipal open data policies, database design, and open-source tools for cleaning and processing spatial data.