Prioritizing Green Infrastructure in New York City: A Framework for Project Implementation and Co-benefits Evaluation

Student | Pankti Mehta
Faculty | Leonel Ponce, Ira Stern
School of Architecture, Graduate Center for Planning and the Environment

With an intent of pursuing the co-benefits of green infrastructure in order to prioritize it over other grey infrastructure technologies, this research is an inquiry on what could be an ideal way to identify, quantify and evaluate the co-benefits of GI practices. How can city agencies like New York City Department of Environmental Protection (NYC DEP) and New York City Housing Authority (NYCHA) accommodate co-benefits in their prioritization and expansion of Green Infrastructure implementation? This research aims to develop a feasibility framework that can help in site selection and GI prioritization and implementation based on its stormwater capture benefits as well as co-benefits.

Green Infrastructure apart from its benefit of capturing stormwater is considered to have multiple co-benefits tightly knit to improve the ecology, economy, health and social impacts of the urban environment.The interwoven connections amongst these benefits has the prospective to address many pressing issues and potential to significantly bring about cumulative improvements.
The NYC Department of Environmental Protection (DEP), regulated by the New York State Department of Environmental Conservation (DEC) is responsible to operate and maintain Green Infrastructure implementation across all city-owned properties. DEP partners with other city agencies like New York City Housing Authority (NYCHA) to deploy green infrastructure practices on their property.
PM2.5 concentrations, 2014 annual average. Source: NYC Community Air survey, Neighbourhood Air Quality 2008-2014, NYC Health
Asthma Emergency hospitalization in relation to NYCHA. Source: NYC Department of Health and Mental Hygiene – Environment and Health Data Portal / United Hospital Fund Boundaries; NYCHA Department of Research and Management Analysis.
The matrix illustrates the relationship between Green Infrastructure practices and its benefits and co-benefits. Each Green Infrastructure practice is demonstrated to have the highlighted benefits. This is a tool to optimize designs to take maximum benefits into consideration, and establish the basis of a priority framework.
The priority framework includes the following steps: site selection and prioritization, green infrastructure (GI) typology selection and prioritization, and GI applicability and efficiency assessment. The second step prioritizes the most appropriate GI practice in a given context through a scorecard. This assists maximization of benefits, and can also incentivise design innovations.
Cost benefit analysis of GI practices can be done to determine cost-effectiveness of a project and its co-benefits. This matrix organizes indicators used to measure value for all the benefits and co-benefits. To calculate the dollar value of each indicator, values accepted by local, state, and federal agencies are used.