NYBG Maps NYC Blue Zones and Flood Risk More than one fifth of New York City is built on what used to be open water, marsh or tidal flats, according to new mapping by scientists at the New York Botanical Garden. These areas, termed “blue zones,” encompass parks, public housing, airports, and entire neighborhoods that currently flood or are projected to flood as sea levels rise and storms intensify. City planners emphasize that the overlap between historic wetlands and today’s dense development is creating difficult choices about where to allocate resources for floodproofing and where to eventually relocate housing and services. The mapping project, led by researchers at the New York Botanical Garden, combined historical ecology reconstructions with modern flood datasets to identify areas that once held rivers, marshes, or tidal flats and now face coastal or pluvial flood risks. The team integrated Welikia historical maps with FEMA flood layers, Department of Environmental Protection stormwater resiliency maps, and 311 flooding reports to create a digital, block-by-block tool. This tool allows users to search citywide and visualize how past water footprints align with current and projected flooding patterns. According to The City, approximately 1.2 million New Yorkers—about 12 percent of the city’s population—reside in blue zones, with roughly 11 percent of buildings located in these areas. The analysis reveals that nearly two-thirds of blue zone land faces coastal flooding risks, while other portions are prone to flooding from intense rainfall or a combination of coastal and rain-driven events. The mapping also highlights that major facilities, including John F.#new_york_city #laguardia_airport #john_f_kennedy_airport #new_york_botanical_garden #department_of_environmental_protection
Blue Zones: Identifying Adaptation Opportunities Using Past, Present, and Future Flooding in New York City Lucinda Royte, manager of urban conservation data, tools, and outreach at the New York Botanical Garden, recently published a paper titled “Blue Zones: Identifying Adaptation Opportunities Using Past, Present, and Future Flooding in New York City” in the Annals of The New York Academy of Sciences. The paper explores how historical ecological data can inform modern flood resilience strategies in the face of climate change. Royte’s interest in the topic was sparked in 2021 during the aftermath of Hurricane Ida, which brought unprecedented rainfall to New York City. The storm’s remnants dumped 3.15 inches of rain in an hour, overwhelming infrastructure designed to handle only 1.75 inches. Royte described walking home through Gowanus Creek, now a heavily polluted canal, where sewage water from overflowing catch basins submerged the area. The experience highlighted the recurring pattern of water returning to historically wet zones, a phenomenon she observed in flood maps. The paper’s central hypothesis is that wet areas will remain vulnerable to flooding, both now and in the future. To test this, Royte and her team at the New York Botanical Garden, under the guidance of Dr. Eric W. Sanderson, developed a comprehensive ecological history dataset of 17th-century New York City. This dataset, the result of a 20-year effort to georeference and digitize historical maps, includes topographical, hydrological, and geological data, as well as information on Indigenous Lenape ecosystems and land use. The team integrated this historical data with current and projected flood risk maps to identify “Blue Zones”—areas that were historically wet, remain wet today, and are projected to be wet in the future.#new_york_city #lucinda_royte #new_york_botanical_garden #eric_w_sanderson #hurricane_ida
A Fifth of NYC Built on Bygone Water Now at Risk: Study Maps City’s 'Blue Zones' A groundbreaking study reveals that more than one-fifth of New York City’s land is classified as a "Blue Zone"—areas historically shaped by water, currently vulnerable to flooding, and projected to remain at risk due to climate change. Researchers from the New York Botanical Garden, in a paper published in the Annals of the New York Academy of Sciences, mapped these zones by analyzing historical water patterns, current flood risks, and future projections. The findings highlight the urgent need for infrastructure upgrades and climate resilience strategies as rising seas and extreme weather threaten the city’s future. The study identifies over 500 Blue Zones across the five boroughs, encompassing more than 20% of the city’s land area. These zones, which include marshes, ponds, streams, and former wetlands, are now home to 1.2 million residents and 11% of the city’s buildings. Eric Sanderson, vice president of urban conservation at the New York Botanical Garden and a co-author of the paper, emphasized the scale of the issue: “Everybody was startled, including us, that it’s more than 20% of the city. That combination—you can’t really argue with it—places that were wet, are wet and will be wet in the future.” The Blue Zones are not just remnants of the past; they are critical indicators of future flood risks. Lucinda Royte, lead author of the study and manager of urban conservation at the Botanical Garden, explained that these areas serve as a guide for planning resilient infrastructure. “It can be a pretty good guide about where we’ll see flooding in the future as a result of coastal flooding from storm surge and sea level rise, and inland flooding from rainfall events,” she said.#new_york_city #new_york_botanical_garden #annals_of_the_new_york_academy_of_sciences #eric_sanderson #lucinda_royte
