New Jersey State Regulatory Riparian Zone Map
Channel: Geo BTAA
Date: 13/11/2023

Kate Douthat, Rutgers, the State University of New Jersey; Larry Torok, New Jersey DEP

This map shows the locations and widths of regulatory riparian zones of the streams of New Jersey according to the Flood Hazard Area Control Act (FHA) Rules (N.J.A.C 7:13-4.1). The FHA designates riparian zones around streams, inside of which development and land disturbance is limited in order to protect target species, habitat, and water quality. The width and upstream extent of the buffer is based on state Surface Water Quality Standards and the location of habitat for endangered and threatened species. The State has a map of surface water quality standards that classifies streams by their type, designated uses, and anti-degradation statuses, but until now, the location of corresponding protective riparian zones was not mapped. Riparian zones had to be interpreted directly from the text of the rules—a complicated task for most users.  Some technical issues we encountered when making this map included reconciling different sets of stream centerlines and creating isodistances with ESRI’s new Trace Network tool. Other challenges included reconciling data definitions and regulatory definitions. The final map is not able to fully translate the rules into GIS due the limitations of the current data, e.g. the location of the top of bank of streams, which is a fine-scale topographic feature that must be identified in the field. However, this map provides the public with a new understanding of the location of riparian zones and stream protections at specific areas of interest as well as landscape-level patterns. 
Introduced by Laura McElfresh