Stormwater Retention Performances of Green Roof under the Tropical Climate of Sarawak
| dc.contributor.author | Chai Chern Tcian | |
| dc.date.accessioned | 2026-10-15T02:05:51Z | |
| dc.date.issued | 2018 | |
| dc.description | The retention performance of the green roof has been widely investigated in developed countries particularly in the temperate climate region. However, available literatures concerning the retention performances in tropical region are scarce. This study is an initial attempt to investigate the retention performance of the green roof under the hot-humid tropical climate specifically in Sarawak through modeling approach. Prior to modeling, the retention capability of an extensive green roof under the actual meteorological condition in Sarawak was demonstrated, indicating 88.1% of mean retention rate and 80.8% of cumulative retention rate. There are only seven rainfall events were captured due to unavailability of suitable instruments and overflow of runoff towards the outlet of downspout pipe during heavy events. By applying twelve month past meteorological data in Kuching, Sibu and Miri into the green roof water balance model, the runoff generated from the green roof models were continuously simulated. When compared to the reported performances from other studies, the modeled results revealed that the high and stable evapotranspiration rate in Sarawak has moderated the unfavorable impact from tropical rainfall towards the long-term retention performance. On event basis, the green roof performed well in stormwater retention for most of the event but performed poorly during the event that potentially triggered the occurrence of flash flood with mean retention rate of 11.5% only. By performing Spearman’s rank correlation analysis, the result shows that the event retention rate was inversely related to rainfall depth and mean rainfall intensity whilst the direct relationship between event retention rate and ADWP was found to be event size dependent. The modeled result also indicated that there were significant variations in monthly retention rate. Correlation analysis revealed that the monthly retention rate was inversely related to monthly rainfall depth. These results suggest that v rainfall depth is the salient meteorological factor that affects both the event and monthly retention rate in Sarawak. Understanding on the relationship between retention and meteorological factors allows the designer to enhance the retention capability of the green roof according to the characteristic of local climatic conditions. Although the result shows that green roof alone is unable to significantly contribute to urban runoff reduction, it may well provide effective and practical contribution towards urban stormwater management in Sarawak when it is incorporated with other BMPs. The modeled performance can be referred as the potential contribution of green roof alone in runoff reduction in future studies that focuses on large scale modeling with different BMPs. | |
| dc.identifier.uri | https://scholarhub.unimas.my/handle/123456789/3077 | |
| dc.language.iso | English | |
| dc.publisher | UNIVERSITI MALAYSIA SARAWAK | |
| dc.relation.ispartofseries | Faculty of Engineering | |
| dc.subject | Retention, green roof, runoff modeling, urban stormwater management | |
| dc.title | Stormwater Retention Performances of Green Roof under the Tropical Climate of Sarawak | |
| dc.type | Masters |