Issue link: https://read.dmtmag.com/i/117518
The New York City (NYC) Department of City Planning embraced this spirit of time travel and began a GIS project that ultimately will allow planners and researchers to do some time travelling of their own through the history of zoning in New York City and use what they learn to influence the zoning future. A Bit about Zoning To provide some context, it may be helpful to explain a bit about zoning, in general, and New York City zoning, in particular. In its most basic sense, zoning determines things such as size and use of buildings, where they can be located and the density of a city's neighborhoods. Along with the city's power to budget, tax and build infrastructure, zoning is a key tool for implementing the planning policy of any municipality. Zoning promotes responsible development; without appropriate zoning codes in place to guide its growth, a city runs the risk of turning into a chaotic jumble. In 1916, New York City adopted the nation's first modern set of zoning codes, one that established rules such as height and setback regulations for vertical structures. As New York grew, so did its zoning code. New theories and ideas influenced city planners along the way. By 1961, the original 1916 zoning resolution was no longer sufficient to meet the needs of a rapidly growing city, and a new zoning resolution was created. Although changes in zoning always are happening through time, the most recent years have been especially active. Since 2002, New York City has undergone major changes to its Zoning Resolution and zoning maps. Approximately 11,000 blocks, or one third of the city, have been rezoned. Today's 1,700-page Zoning Resolution reflects a synthesis of planners' ideas—new and old—that have guided city development since the early 1900s. set of binders—yes, the Department of City Planning has binders full of zoning maps. By 2004, this set contained more than 2,000 "historical" zoning maps, each representing a snapshot view of NYC's zoning at a discrete point in time within a defined area of the city's overall zoning map. This is a complete chronological record of where and how zoning has changed in New York City—a zoning time machine in analog, hardcopy format. The maps were scanned and georeferenced, and the extents of the changed areas were captured as polygons. The imagery and GIS data obtained from that set of historical zoning maps made this "time-travel" project possible. NYC Zoning in GIS What was missing in 2004 was a present-day GIS zoning dataset that modeled zoning as continuous, citywide polygon layers as shown on zoning maps, but work on creating such data was completed in 2007. After a period of internal use and evaluation, June 2009 saw the data finally released to the public as a monthly updated free download. The zoning dataset consists of three polygon feature classes: 1. Zoning districts 2. Commercial-overlay districts 3. Special-purpose districts Zoning districts, at the most basic level, differentiate among residential, commercial and manufacturing districts, fairly typical for any city's zoning. Commercialoverlay districts are subareas within residential Mapping Historical Zoning Included within the New York City Zoning Resolution is a set of 126 zoning maps, describing in dimensioned detail the location of various zoning districts throughout the city. The text of the Zoning Resolution describes zoning regulations, and the maps tell what the particular zoning is at specific locations. The districts shown in these maps have changed through time along with the Zoning Resolution's text. Changes to the zoning maps can be proposed by private developers, city agencies and other interested parties for adoption by the City Planning Commission and City Council. Printed updates to the Zoning Resolution are made once or twice a year and include any zoning maps that have been changed. Since 1961, copies of every printed version of each zoning map have been preserved in a A figure indicates New York City zoning changes since 1961 as well as a Zoning Map Index. M A R C H 2 O 1 3 / W W W . G E O P L A C E . C O M 15