Abstract
Green roof systems could help reduce peak discharge and retain rainwater in urban areas. The objective of this study was to investigate the hydrological behavior of a green roof system by using the SEEP/W model. The rainfall-runoff relationship within the green roof system was simulated and the results were compared with actual data from a test bed for green roof systems to verify the applicability of SEEP/W. Then, the verified SEEP/W model was used to simulate the green roof system by varying four factors (soil type, rainfall intensity, substrate depth, and green roof slope) to explore the hydrological performance through the peak discharge to rainfall intensity (PD/RI) ratio and the rain water retention rate. The results show that the model presents slightly faster and greater peak time and peak discharge values, respectively, as compared to the observational data. This is attributed to the vegetation conditions in the real green roof system. However, it is also shown that the SEEP/W model can be used to design green roof systems and evaluate their hydrological behavior because of its modeling efficiency. Thus, the SEEP/W model can be used to reliably design and manage green roof systems by further considering the vegetation conditions and water flow dynamics. Furthermore, it would be desirable to consider additional factors, such as vegetation and an insulating pebble layer, in the design and management of green roofs in future work.
Highlights
The acceleration of urbanization has induced the stronger impermeability of the subsurface, as farmland, green land, and forest have been replaced by buildings, roads, and pavement (Mentens et al, 2006; Li et al, 2018; Yan et al, 2019)
The objective of this study was to investigate the hydrological behavior of a green roof system by using the SEEP/W model
The objective of this study was to investigate the hydrological behavior of a green roof system by using the SEEP/W model, for design and management purposes
Summary
The acceleration of urbanization has induced the stronger impermeability of the subsurface, as farmland, green land, and forest have been replaced by buildings, roads, and pavement (Mentens et al, 2006; Li et al, 2018; Yan et al, 2019). The main environmental problem caused by these impermeable sub-surfaces is that urban hydrological systems should manage a highly fluctuating runoff, which is significantly high during stormwater season (White, 2002). Conventional stormwater systems have only been used for flood reduction and management, while the environmental problems related to urbanization have not been considered (Carter and Fowler, 2008). Green roof systems can be an effective and eco-friendly rainfall management tool for problems related to uncertain water flows. Green roof systems can provide environmental benefits such as rainwater retention, peak discharge reduction, and runoff delay (Getter and Rowe, 2006; Feitosa and Wilkinson, 2016; Soulis et al, 2017; Shafique et al, 2018).
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
