An Evaluation of Material Stocks and Flows Found during Construction and Demolition Activities in the Philadelphia Region of the United States
Authors:   , Marcellus-Zamora Kimberlee Angelita , Gallagher Patricia M. , Spatari Sabrina 
Published: July 2021

When you throw something away, where is away? The infrastructure to support the built environment is a big consumer of energy and valuable natural resources. The waste managers' sustainability battle-cry 'reduce, reuse, recycle' is becoming more popular within the construction industry however more research and data are necessary to provide proof of success. Recycling C&D waste is relatively easy to achieve on construction sites, but difficult to track and quantify. Waste generated from construction and demolition (C&D) activities are rich in salvageable, reusable, and recyclable content. Determining the material fractions present in waste flows, stocked materials, and secondary markets is critical to understanding the value of these resources and extending their use in the economy by refurbishment, recycling or new use. Construction waste management (CWM) has a cross section of designers, contractors, and decision makers and we need to make the life cycle pathway of materials in construction/demolition processes more transparent to construction industry stakeholders. Providing better transparency in these materials may motivate these individuals to recycle and reuse demolished materials, reduce consumption of virgin materials and to begin to document this progress regionally. This dissertation provides three papers with the goal of quantifying and evaluating environmental and resource management aspects of materials that are: 1) stocked in place, 2) present in waste flows, and 3) retired and installed during renovation activities. This research informs the waste management industry on building material movement and strategies for their reuse and recycle in Philadelphia. The first study shows that characterizing buildings by land use type is a viable means for determining materials stocked in place in buildings located in the city of Philadelphia. The method could be applicable to other cities in the US with similar patterns of development and urban form as Philadelphia, the city tested herein. The second study conducts data acquisition from unconventional sources including United States Green Building Council (USGBC) completed projects database, private industry waste reclamation facility (WRF) annual waste diversion data as a means to qualify materials found in C&D waste flows. We provide a contemporary C&D waste MFA dataset and find major fractions present in the WRF flows. The last study demonstrates atypical methods for sampling C&D waste data in the city of Philadelphia through publicly available data. We sample data from local governments that have not been previously used in industrial ecology research in order to characterize waste that is generated during permitting activities. The method could be applied in other urban centers in the US. The thesis demonstrates that industrial ecology tools, when combined with private data and alternative and publicly available data sources can describe and potentially quantify waste materials that are being diverted from landfills.