St George/te Statlew Rainway

Urban Heat Island Effects and Biodiversity Monitoring Plan 

Xiaotong Ding, Zhenyang Sun, Gurtaj Virk, and Lindsay Yeung 


The object of this report is to develop a data analysis and monitoring method that can be used to assess the environmental and community co-benefits of GRI, specifically biodiversity enhancements and reduction in UHI effects provided by the St George street rainway project. The proposal aims to provide a realistic plan that can be implemented by the city. The proposal as well as exploring the benefits of GRI within the literature, the report seeks to explore the efficacy and ease of implementation of citizen science as a method to collect data. The recommendations included in the data monitoring plan should be viable to implement, realistic in budget and provide the most accurate data possible. The rainway is being implemented for the public, this report's main aim is to provide an avenue through which the city may quantify the benefits of the rainway to better communicate the full effect of the project on the community to the public. 

Next Steps

7.1 Biodiversity

Once the biodiversity impacts of the rainway have been assessed, further biodiversity goals can be set. While increasing urban biodiversity has many positive effects on the urban environment, it can only support a limited amount of wildlife, and changes in biodiversity may impact urban residents. Feedback specific to the increased biodiversity in the area should be solicited from residents on St. George Street and the surrounding neighbourhoods. Residents may be asked some of the following questions to gauge how changes in biodiversity are affecting their neighbourhood and homes:

  • ●  Have you noticed changes in the usual wildlife in your neighbourhood or around your home? Such as more, less, or different wildlife? Think of animals, insects, and plants.

  • ●  Has this wildlife had any effect, positive or negative, on your daily life?

  • ●  Has this wildlife had any effect, positive or negative, on the physical state of the

    neighbourhood or your home?

It is possible an increase in biodiversity may introduce wildlife to the area that is deemed undesirable by local residents. For example, things like an increase in the number of flying insects may bother some residents or an increase in burrowing animals that disturb lawns and gardens.

To gain full public support for the rainway and future GRI projects, there must be a balance between the environmental and social impacts of increased biodiversity. If further increases to biodiversity are desired, consideration of the urban environment’s ability to support it, and the public’s ability to support it, must be considered.

7.2 Urban Heat Island Impacts

After completing the monitoring and data analysis of land surface temperature by satellite and sensitive organisms, our team chooses to use the canopy closure rate of trees to monitor further UHI effects. Canopy closure rate means the percentage of tree canopy sheltered from direct sunlight (Murphy, 2021). A higher ratio of canopy closure can effectively reduce the surface temperature, thus reducing the UHI impacts (Greene & Millward, 2017). Simultaneously, it will improve the quality of life and activities' range of some temperature-sensitive organisms to facilitate our monitoring and observation of these organisms. Then, further analyze the relationship between satellite measurement data, canopy closure rate, and sensitive organisms, we may find the correlation among these three variables, which will improve the accuracy of all monitoring data. Our group chose Strickler (1959) Method to calculate the canopy closure rate, which can avoid the repeated calculation problem of a convex spherical densitometer (Murphy, 2021). We divide St. George into two parts and calculate the canopy closure rate of each part. The first part is that there are only trees and no residential buildings near the street, and the other part is that there are both trees and residential buildings. Ten sites were selected for each part, and the average value of the canopy closure rate can be calculated. According to the percentage of the two parts in the total Street area and the independent canopy closure rate, we can calculate the average rate of the total canopy closure with the formula (Murphy, 2021).

Different tree species have different canopy closure rates. Our group recommends planting linden on both sides of St. George. Linden does not wither in winter because it is almost evergreen. The canopy closure rate will not decrease even in winter. Linden is not easily threatened by pests and has a large and loose canopy, providing a vast shadow and canopyclosure rate. Moreover, the Vancouver government has chosen to plant some varieties of linden on both sides of the street (City of Vancouver, 2012), which proves that linden is suitable for growing in Vancouver and meets the Vancouver government's standards. 

Research Poster

Final Report