A brownfield sites is “any abandoned or underutilized site where redevelopment, reuse or expansion has not occurred due to the presence or potential presence of pollution in the buildings, soil or groundwater that requires investigation or remediation before or in conjunction with the restoration, redevelopment, reuse and expansion of the property” (state of Connecticut). Brownfield sites can cause harm to the built and the natural environment. In the city of Detroit environmental planning and sustainability efforts are needed in order to revitalize neighborhoods. Some neighborhoods in the city of Detroit appear to be abandoned and have brownfield sites within the area. According to ACS 2015 data, the Detroit median household income was $25,764. The city of Detroit has not only experienced economic challenges but the city has also experienced environmental challenges. Areas of Detroit that have high poverty levels also have issues with environmental planning and sustainability. Environmental unjust practices are questionable within the city of Detroit. For this directed study the alternate hypothesis is; “more brownfield sites are located near areas with low household income levels.” The null hypothesis is that there is no relationship between the two variables. The number of brownfield sites is the dependent variable and the household income levels will be the independent variable. Brownfield sites within the block group level of the city of Detroit are analyzed and counted along with an analysis of household income at the Detroit block group level.
Within this directed study 2015 ACS data and G.I.S ArcMap software was used in order to analyze the relationship between brownfield sites and household income levels. A map of the city of Detroit was added onto ArcMap and labeled as the study area. The data was downloaded from the ACS census website for median household income levels at the Detroit block group level. The number of brownfield sites data was added to ArcMap from the website homefacts.com. The excel file that contained the median household income data and the data for Detroit block groups was added onto ArcMap. In order to analyze the count of the number of brownfield sites along with the household income a join table was created by joining Detroit Block groups and the excel file for the median household income. A spatial join was created in order to join the tables of Detroit block groups and the number of brownfield sites. The spatial join displayed the count of the number of brownfield sites within each polygon. After the spatial join was completed and produced a join output of the number of brownfield sites at the Detroit block group level, a table join of the household income levels was completed. After joining the median household income table and the join output table, the household income and the count of the number of brownfield sites were displayed within the attribute table. A few discrepancies were produced from the joins. For example; the count of the number of sites was overestimated within a few polygons because of the sites’ (points) closeness to the polygon’s boundary lines. In order to check the accuracy of the brownfield count data within the join output attribute table, the sum of the number sites within the sites attribute table was compared to the join output table. The sum for both attribute tables (join output and the site attribute table) was 804 brownfield sites.
The number of brownfield sites at the block group level produced a descending line for a scatter plot that can be seen in figure 1 below. We reject the null hypothesis of neither variables having a relationship. The number of brownfield sites is related to median household income. The areas that have low household income levels have the highest count of brownfield sites within the area. Household income levels between $15,000 and $50,000 have the highest count of brownfield sites, while areas that have household incomes between $80,000 and $135,000 have the lowest count of brownfield sites.
Figure 1. Number of Brownfield Sites at the Detroit Block Group Level versus Median Household Income
I will post the graph that I made soon :). I apologize for the technical difficulties.
Figure 2. Map of the city of Detroit with Block Groups and Brownfield Sites from ArcMap
Figure 2. Map of city of Detroit with Block Groups and Brownfield Sites from ArcMap
The areas with the low household income levels have the highest number of brownfield sites within the area. The graph displays the correlation of income and environmental hazard exposure. Revitalization is needed for the most vulnerable neighborhoods within the city. The neighborhoods can also benefit from economic development. The median household income in 2015 for the city of Detroit was $24,764, within this income bracket there are a high number of brownfield sites according to figure 1. Environmental unjust practices within the city of Detroit need to be addressed.
Bureau, U. S. (2015). Factfinder.census.gov. American Fact Finder.
Protection, S. o. (2017, March 28). Brownfield sites in Connecticut. Retrieved from ct.gov: http://www.ct.gov/deep/cwp/view.asp?A=2715&Q=324930