Mohamed Roseli Zainal Abidin’s research while affiliated with Universiti Tenaga Nasional and other places

Efforts have been made by the government agency to install the Gross Pollutant Trap (GPT) to protect of entering the gross pollutants from direct discharge into the river. Few studies have been performed in related to GPT and there is a need to do research on the performance of GPTs in Malaysia. The performance of GPTs is strongly dependent on installed location. Moreover, contribution of landuse has also potential to evaluate the GPTs performance. The main objective of this paper is to analyse the wet load that has been trapped inside GPTs. In this study, Installation of GPTs are performed based continuous deflective separation (CDS) and downstream defender (DD). Kemensah River is chosen as a case study and GPTs are installed at drainage systems due to analysis the impact of GPTs on reduction of solid waste from discharge to the Kemensah River. The result shows that the GPTs can reduce the gross pollutants before entering the river system in optimum way. Consequently, the area of catchment, dense residential area and rainy season have important role on increasing the gross pollutant.

Rapid urbanization in the recent decades has quickly fuelled up the process of global warming. Many mitigation measures have been formulated and implemented in order to tackle the effect of global warming. Green roofs (roof with vegetated cover) have been proposed and implemented by various countries as one of the new environmentally friendly innovation. This paper evaluates the qualitative and quantitative performances of an extensive green roof system under tropical climate. Simulations showed that the peak discharge of stormwater run-off was reduced up to 26% in relation to concrete tile roof. Its reduction ability was decreased for storms with intense rainfall. Increment of pH was observed for the green roof run-off, and the run-off quality ranged between class I and II under Malaysia National Water Quality Index (WQI). High concentrations of phosphate were observed in the run-off samples, which showed that substrates (fertilized planting soil) might be the potential contributor. Findings indicated that there was a reduction up to around 5% for indoor temperature of the building after installation of the extensive green roof system. * LINK: http://www.tandfonline.com/doi/pdf/10.1080/15715124.2015.1048456#.VcoEoWoVjIU

With respect to the current vulnerable climatic condition, water quality has become a matter of the highest worldwide concern. Rainwater harvesting is the most acceptable solution for overcoming this problem. Among various rainwater harvesting systems, green roof rainwater harvesting is a significant tool for improving the standard of living for rapidly growing populations in the whole world, in terms of both water demand and protecting the environment from pollution. This paper assesses the water quality parameter (dissolved oxygen (DO), pH, conductivity, and temperature) of rainwater harvesting from green roofs in humid tropic center under tropical climate conditions. It shows that the values of electric conductivity are always within Class I according to Interim National Water Quality Standards (INWQS) and Water Quality Index (WQI). Depletions of DO and pH values were observed for the green roof runoff, and the runoff quality ranged between Class I and III under INWQS and WQI. Lower value of pH indicates that harvested rainwater from green roofs is more acidic than the standard neutral value. Harvested water must be processed through general water treatment methods like filtration, disinfection, and through reverse osmosis storage tank. The indoor temperatures are always within an acceptable range.

Promoting green design, construction, reconstruction and operation of buildings has never been more critical than now due to the ever increasing greenhouse gas emissions and rapid urbanizations that are fuelling climate change more quickly. Driven by environmental needs, Green Building Index (GBI) was founded in Malaysia to drive initiative to lead the property industry towards becoming more environment-friendly. Green roof system is one of the assessment criteria of this rating system which is under category of sustainable site planning and management. An extensive green roof was constructed in Humid Tropics Center (HTC) Kuala Lumpur as one of the components for Stormwater Management Ecohydrology (SME) in order to obtain scientific data of the system. This paper evaluates the performance of extensive green roof at Humid Tropics Center with respect to urban heat island mitigation and stormwater quantity and quality controls. Findings indicate that there was a reduction of around 1.5°C for indoor temperature of the building after installation of green roof. Simulations showed that the peak discharge was reduced up to 24% relative to impervious brown roof. The results show an increment of pH and high concentration of phosphate for the runoff generated from the green roof and the runoff water quality ranged between class I and II under INWQS.

Langat River is 180 km length has a total catchment area of 2,350 km2. The Langat River is classified as Class II in the upstream, and as the water flows downstream the quality degrades to Class III and IV. This degradation is caused by the rapid and uncontrolled urbanization in the contributing catchment of the river. The characteristics of the river and its contributing catchment are modeled using Model for Urban Stormwater Improvement Conceptualisation (MUSIC) in order to rehabilitate the river and enhance its Water Quality Index (WQI) to Class II. The historical rainfall data was obtained from DID for the period from 1974 to 2012. This paper presents the effects of various BMP Components on rehabilitating the water quality of the river. In addition, the minimum amount of river flow required for protection of the habitats and the river's ecology has been assessed during the dry seasons. The outcomes of this study suggest the most appropriate Best Management Practices that can be used as solutions for the river's rehabilitation. Simulations and modeling result found out that a configuration of wetlands, bio-retention systems and ponds are capable to reduce pollutants loadings such as TSS, TP and TN by 85.1%, 69.1% and 37.5% respectively