Optimizing recycling in all of New York City's neighborhoods: Using GIS to develop the REAP index for improved recycling education, awareness, and participation

New York City's recycling program began in 1988 with scattered pilot programs to collect a restricted number of recyclable categories. Over time, the program was made more uniform in its implementation, was expanded citywide, and targeted more types of recyclables. Although Department of Sanitation surveys have shown that residents in all areas of the city have understood the requirements of the recycling program, recycling diversion rates vary substantially throughout the city's neighborhoods, ranging from 9 to 31% per district, while city-wide the diversion rate averages only about 20%.This paper explores the possible reasons for the disparity of recycling participation rates amongst neighborhoods, using recycling data collected by the city and federal census information to characterize the city's neighborhoods and show variation in recycling participation rates, demographics, socio-economic indicators, and other metrics. Four variables were found to be strongly correlated with low diversion rates: percentage of persons below poverty level; percentage of households headed by a single female with children; percentage of adults without a high school diploma; and percentage of minority population.A weighted linear model is used to calculate a one-number descriptive measure, called the recycling education, awareness, and participation (REAP) index, which relates recycling behavior for each of New York City's 59 sanitation districts with demographic and socio-economic variables that might “predict” recycling rates. This REAP index can then be used to help inform decision- and policy-making about strategies for increasing recycling education, awareness, and participation, help target particular communities for assistance, and prioritize resources. The effects of rapid program changes and substandard residential recycling environments are also discussed as possible influences on recycling participation rates, as well as other attitudinal, physical, and knowledge-based factors that may be indirectly associated with low socio-economic status communities.