In February 2004, the MTA re-opened the north tracks of the Manhattan Bridge with new service patterns. This resulted in the ability to have a one-seat express ride from Chinatown in Manhattan to the Southern Brooklyn neighborhoods of Sunset Park, Bensonhurst, and Dyker Heights. In the decades since this service change, we have observed a fraying of the once-clustered Chinatown in Manhattan and the development of ethnic enclaves in Southern Brooklyn. Our study charts how this shift has affected a variety of metrics relevant to ethnic enclaves.

Our methodology followed a three step approach: first, we identified clusters at the scale of New York City using Getis Ord Gi* Clustering. We then compared these clusters more deeply by using Duncan’s Dissimilarity Index, which helped us define boundaries for our enclaves. We then developed Multi-Modal Service Areas originating from the centroids of those boundaries for each study year. The results, below right, paint a complicated picture on how various measurements of life in the city have affected the ethnic enclave near the foot of the Manhattan Bridge. The 20 years post-service changes are clearly servicing a greatly different Lower Manhattan, one with higher property values, greater connectivity to the city, and lower percentage of immigrant residents.