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Sustainable Affordable Housing Site Selection in San Francisco LAc188 Applied Project | Mari Hayashi, Jiechun Lei, Zhida Wang | Dec 11, 2015 Network Analysis Suitability Analysis We conduct a general suitability analysis based on the following criteria: We suggest our clients to build sustainable affordable housing next to existing roads and public transit stops to support low carbon transporation. Additionally, we suggest that sites should be away from major landmarks and highways to avoid noise, pollution and for safety concern. In short, all factors are presented below: Opportunities (Each weight 1): 100’ from existing streets 300’ from population > 1500 500’ from public transit stops Constraints (Each weight -1): 300’ from landmarks 500’ from existing highways Geo-Data (TIN) Analysis It is essential for residents of sustainable affordable housing to have access to facilities and services. Hence, we conduct a service area analysis to find out areas best served by local groceries, health services including hospitals and general clinics, and educational institutions including elementary and primary schools. We then assign weight for each feature class and make sure that different travel times are weighed according to the scale of weight for the final suitability analysis. The specific weight assignment is shown below: Travel Time to Groceries (by car, minute) 1 : weight 2 2 : weight 1 3 : weight 0 4 : weight -1 5 : weight -2 Travel Time to Health Services (by car, minute) 1 : weight 1 2 : weight 0 3 : weight -1 Travel Time to Schools (by car, minute) 1 : weight 2 2 : weight 1 3 : weight 0 4 : weight -1 5 : weight -2 We believe that one of the significant features of sustainable affordable housing is that residents are encouraged to walk or bike more to promote less carbon emission. However, walking or biking could be difficult in many hills of San Francisco with their steep slopes. As a result, steep slope has become one of the constraint factors in our analysis so that our clients could avoid areas that are too steep for residents to bike or walk comfortably. After conducting the Geo-Data analysis, we produce the map above in which the dark green areas represent ideal zones in San Francisco where slope is 0 degree. Accordingly, red areas with slope greater than 20 degrees are crossed out in our final analysis. We compose the final suitability map of sustainable affordable housing sites, as shown above, through combining the result of network analysis with the general suitability analysis, and highlighting areas with slope greater than 20 degree on the suitability map to produce the final map. To sum up, areas presented in dark green in the final map are ideal sites for sustainable affordable housing development, such as the Mission Bay district, the Inner Richmond, and neighborhoods around the Bernal Heights. It should be noted that some areas that score very high in suitability analysis are eliminated simply because of their steep slopes. We also conclude that identification of potential residents and application of existing affordable housing suitability models could furthermore narrow down our results, though our findings have already showcased a variety of choices for real estate developers to consider. Produced by Mari Hayashi, Jiechun Lei, Zhida Wang Dec 11, 2015 Final Suitability Map for Sustainable Affordable Housing Sites Flow Chart Introduction Clients Problem Statement Methods Conclusion Sources, Projection & Datum We collect data from the following sources: Google Earth; U.S. Geological Survey; Metropolitan Transportation Commission Open Data; San Francisco Data Catalog; US Census Bureau; LA C188 class website. We use the same projection and datum for all maps in this poster-- Geographic Coordinate System: GCS_WGS_1984; Datum: D_WGS_1984. City & County of San Francisco Mayor's Office of Housing and Community Development S.F. Housing Development Corporation (SFHDC) A nonprofit developer that builds and manages affordable housing units City planners have been using GIS to select location to build low- income housing to ensure that the urban poor has equal access to basic services and resources. In this project, we propose to incorporate sustainability features into affordable housing site selection criteria to help our clients to develop sustainable affordable housing that could further reduce living costs, alleviate burden on the environment, and improve the public's health. Our analysis addresses the following research questions: How to find the best locations in SF to develop housing units that are environmentally sustainable and economically affordable? What are some of the best locations? After identifying the selection criteria, we utilize three models that are TIN, network and suitability analysis, to generate a final suitability map to answer our questions as illustrated in the flowchart and detailed in each sub-section. Travel Time to Schools Travel Time to Health Services Travel Time to Groceries
