Modelling of Dam-Weir Operations for Environmental Quality

It is the desire of many societies to have clean and safe potable water sources. As manmade structures are built in water supply catchments for the purposes to increase safe yield, then facilities management of these structures should be steered towards environmental quality. Hydraulics over a weir is well studied. However, this paper probes into benchmarking of flows over a Batu Kitang Weir to guide operations of an upstream Bengoh Dam in Sarawak, Malaysia. Flow releases from the dam are tried and routed through Sarawak Kiri River to achieve supercritical states at weir by means of computer modelling. For daily dam-weir operations, the modelling results suggest a condition of 20 m3/s < dam releases < 200 m3/s to meet raw water demand as well as adequate river flow regulation

Green building technology initiatives to achieve construction quality and environmental sustainability in the construction industry in Malaysia

construction industry to enhance environmental concerns and the adoption of capacity development model to manage the environment and up keeping of the quality in Malaysian construction industry. Design/methodology/approach – This paper describes an innovative approach to understanding the role of internal and external influence through LEGO® concept. This approach builds on the theory of change management, in which includes learning about the domain of enabling environment, organisation, individual and knowledge management process. New ideas, practices or technologies occur through integration of efforts particularly from the above mentioned domains. The approach also analyses the challenges faced by construction stakeholders. It draws on findings from different studies including some other countries of sustainability in which the engagement of previous research has been incorporated to further enhance the construction and environmental quality in the Malaysian construction industry. Findings – Environmental sustainable development construction requires a holistic thinking and decision making and more innovative solutions that enhance sustainability and result in mutually benefited outcomes for all stakeholders. A dedicated effort especially government and government link company is in strong demand. A valid reason for capacity development to develop in organisations and individuals to perform functions needed to keep green management operating and evolving to meet new challenges. The construction sector will benefit from learning advances in capacity development which are designed to improve and enhance construction and environmental quality governance. The coverage of LEGO® conceptual framework at which capacity development operates was identified in each domain of change management. Research limitations/implications – A limitation of the study was the relatively little literature information provided and thus affects the expounding and reliability of data. For this reason, these findings cannot be generalised to the other countries based on this study alone. The access to information is limited as public and private organisations hesitate to share information on their strategic planning and tactics. Originality/value – Development of capacity development model will contribute to the understanding of environmental sustainability through identifying gaps in the understanding and pursuit of construction and environmental quality in the Malaysian construction industry. This paper suggests the future prospect that integrates several dimensions towards green management practice in Malaysia

Use of InfoWorks River Simulation (RS) in Sungai Sarawak Kanan Modeling

The main purpose of this project was to reconstruct historical flood events at the flood-prone Sungai Sarawak Kanan to obtain flood hydrographs to provide explanation to the flooding of Bau town and surrounding areas. The Sungai Sarawak Kanan and its floodplains were modeled using one-dimensional hydrodynamic modeling approach, by utilising the Wallingford Software model - InfoWorks River Simulation (RS), coupled with its embedded GIS applications, to capture the hydraulic response of the river and its floodplains in extreme flooding conditions. InfoWorks RS was applied on 23 km of Sungai Sarawak Kanan between Buan Bidi and Siniawan. The model was calibrated with 3 storm events, verified with another 2 sets of storm data and applied on reconstructing 2 extreme events of February 2003 and January 2004 floods where the correlation of observed and simulated data at Siniawan were between 0.87 – 0.98. The differences of observed and modeled peak water levels were within the allowable limit of ± 0.10 m. Similar efficiency had been achieved in the interpretation on the simulation of reconstruction results through analysis of flood depths and flood watermarks. The model was managed to estimate the flood depths and flood watermarks within the observation range by Department of Irrigation and Drainage Sarawak. This shown that InfoWorks RS is an appropriate model for flood modeling in Sungai Sarawak Kanan

Modelling the Outlet of Multi-Chamber Stormwater Detention System

Outlet size influences the detention volume that is crucial in a stormwater system. This paper describes an application of improving the outlet size of such a system. A field test is built in a terraced house that consists of a 4.40m x 4.70m x 0.45m multi-chamber stormwater detention tank connected to 0.1m diameter inlet and 0.05m diameter outlet. During field monitoring, an overtopping event is observed that puts a quest to re-look into its design. The field test has enabled the data collection of ten storm events with peak rainfall ranging from 20-48mm. A stormwater detention model is developed using the US Environmental Protection Agency’s Storm Water Management Model (SWMM). Calibration of the model with the observed storm events has returned with good matches with R Square values more than 0.9.With the calibrated model, investigations into the outlet sizes of 0.050m, 0.055m and 0.063m are carried out. The existing field test setup with the outlet size of 0.050m has water levels in the detention tank higher than the expected design values; and therefore, overtopping is observed for rainfall depth over 40mm. By simulating a scenario of enlarging the outlet size to 0.055m, the system is improved to accommodate rainfall depth up to 45mm, but overtopping is expected for rainfall depth over 45mm. By simulating another scenario of enlarging the outlet size further to 0.063m, the possibility of overtopping is eliminated but at a cost of achieving only in average 10% of attenuation between peak inflow and peak outflow. It is the least attenuation rate compared to average 30% for 0.050m and 20% for 0.055m. In short, the modelling efforts are demonstrated as a practical solution to the improvement of the intended stormwater detention system

A Study of Ecological Sanitation As A Way To Combat Urban Water Stress

Water supply is one of the basic infrastructure requirements. Water treatment and supply are often granted a much higher priority than wastewater collection and treatment, despite the fact that wastewater deserves a greater emphasis due to the impact of its poor management has on public health. A new commitment to give wastewater the same priority as water supply is a very positive development. A pilot project of greywater ecological treatment is established in Kuching city since 2003. Such treatment facility opens up an opportunity of wastewater reclamation for reuse as secondary sources of water for non-consumptive purposes. This paper aims in exploring the potential of the intended purposes in the newly developed ecological treatment project. By utilising the Wallingford Software model, InfoWorks WS (Water Supply) is employed to carry out a hydraulic modeling of a hypothetical greywater recycling system as an integrated part of the Kuching urban water supply, where the greywater is treated, recycled and reused in the domestic environment. The modeling efforts had shown water saving of more than 50% from the investigated system reinstating that the system presents an alternative water source worth-investing in an urban environment

Environmental Technology: Potential of Merging Road Pavement with Stormwater Detention

This study stresses on the concept of multi-functional urban land use incorporating permeable pavement integrated with underground storage. Permeable pavement that is available in the market consists of pavers and a thick layer of course aggregates that store water. Contrary to the mentioned pavement, this study tries to replace the underlying storage with blocks of concrete detention cells. Stormwater permeates through the openings of pavers and flows into the detention storage underneath. Investigation of such application is carried out using the SWMM software. Performance of a single hollow cube pavement block (0.25m x 0.25m x 0.25m) is demonstrated here. The block is virtually subjected to the worst scenarios of extreme rainfalls over a non-stop time span of three hours. Modelling outputs point to encouraging benefits of the anticipated size and storage volume are capable of capturing stormwater up to at least one hour. Thus, the system is suggested to be effective in limiting stormwater, and subsequently, promoting road structure as multi-purpose infrastructure

Ecological Sanitation, Sustainable Strategy as an Alternative Urban Water Source

Water supply is one of the basic infrastructure requirements. Water treatment and supply are often granted a much higher priority than wastewater collection and treatment, despite the fact that wastewater deserves a greater emphasis due to the impact of its poor management has on public health. A new commitment to give wastewater the same priority as water supply is a very positive development. A pilot project of greywater ecological treatment is established in Kuching city since 2003. Such treatment facility opens up an opportunity of wastewater reclamation for reuse as secondary sources of water for non-consumptive purposes. This paper aims in exploring the potential of the intended purposes in the newly developed ecological treatment project. By utilizing the Wallingford Software model, InfoWorks WS (Water Supply) is employed to carry out a hydraulic modeling of a hypothetical greywater recycling system as an integrated part of the Kuching urban water supply, where the greywater is treated, recycled and reused in the domestic environment. The modeling efforts had shown water saving of more than 50% from the investigated system reinstating that the system presents an alternative water source worth-investing in an urban environment

Modelling of msmacomponents: Porous pavement with detention system underneath for low traffic roads

This study has been made in order to pursue practices in Water Sensitive Urban Design (WSUD), where stormwater management becomes a mainstream in Malaysia. The main focus of this study is to develop a stormwater conveyance model incorporating porous pavement and on-site detention system at Heights Drive (Stutong), Kuching City, and to investigate its effectiveness. Conventional pavements are impervious and create contaminated runoff. In contrast, combination of porous pavement with storage as WSUD approach allows stormwater to percolate to an underlying detention system where stormwater is both infiltrated to underlying clay soil and discharged with a lower rate to drain beside the road. Nine roads with total surface area of 12,660 m2 are selected and a total of 6 scenarios are modelled and simulated using EPA’s SWMM 5.0. It is found that the peak discharge at outfall from the study area is decreased by 23%, in which 2% of the stormwater is infiltrated to the ground for groundwater recharge

Testing the Concept of Mitigating Urban Flooding with Permeable Road: Case Study of Tong Wei Tah Street, Kuching City, Sarawak, Malaysia

This paper describes the investigation of permeable road as a mitigation measure for urban flooding. The study involves the reconstruction of a historical case of inundation, namely the 11 December 2019 flood event along the Tong Wei Tah Street in Greater Kuching City, Sarawak, Malaysia. The Storm Water Management Model version 5.0 was used as the platform to describe the flooding at the selected site and the functionality of permeable road to alleviate flooding. A permeable road with a dimension of 200 m long, 6 m wide and 1 m deep was used to simulate runoff after a structure was installed along the whole stretch of Tong Wei Tah Street. The model results show that flooding was caused by a backwater effect in the drainage system. Models predicted 0.1 to 0.5 m flood depths which matched the observed 0.3 m flood depth account of a local resident. The permeable road exhibited capability to absorb all the out-of-drain floodwaters, leaving no water due to the 11 December 2019 flood on the street. Modelling efforts demonstrated that the floodwater hydrographs in the drain rose and fell within 7 hours, while the underground storage, filled and drained within 13 hours. Moreover, the storage of permeable road was found to fill up to 75%, reserving the unfilled 25% for adverse weathers