Urban Rainfall-Runoff Study To Validate The Design Chart In The Malaysian Urban Storm Water Management Manual (MSMA).

Knowledge on rainfall-runoff response is vital in engineering practices for developing area in the humid tropics. This paper will discuss the runoff response due to varying rainfall within small Malaysian urban catchment

Flash flood susceptibility modelling: a review

Flash flood is common problem in the developed or developing country especially in urban areas. This is due to the changes of land use, poor planning of drainage system, deforestation and unplanned land use and etc. Flash flood susceptibility modelling (FFSM) for urban area is important to avoid the loss and etc. FFSM can be vital component and essential tools for planning and management of natural disaster and environmental. The objective of this paper is to review selected paper on flash flood susceptibility modelling using Geographic Information System (GIS) coupling empirical models. A lot of methods have been coupling with GIS to developed flood susceptibility modelling, for example, Weight of Evidence, Random Forest, etc. However, there is still lack of susceptibility model for flash flood. The GIS coupling method can improve the accuracy of flood susceptibility modelling. Thus, this paper will review the ability of GIS coupling with empirical models for the flash flood susceptibility modelling

Enhancement of Landfill Daily Cover in Minimizing the Migration of Heavy Metals in Landfill Leachate by Using Natural Soil, Pressmud Empty Fruit Bunch (EFB) in PulauBurung Landfill

This study emphasizes on the removal of heavy metals in landfill leachate by using natural soil mixed with agricultural wastes. The agricultural wastes used in this study werenatural soil or known as laterite soil, pressmud which is a waste from sugar refinery process and Empty Fruit Bunch (EFB), one of many forms of waste fromoil palm industry. The laterite soil was mixed with these wastes at different percentages of weight ratio namely 50S:40P:10E, 50S:30P:20E, 50S:25P:25E, 50S:10P:40E and 50S:20P:30E. The terms S, P and E each refers to soil, pressmud and empty fruit bunch respectively.Removal efficiency tests were also carried out and the results showed that the mixtures of laterite soil have the ability to remove concentrationsof As2+, Cd2+, Cr2+, Cu2+, Fe2+, Ni2+ and Zn2+between a range of 86% (minimum) and 99% (maximum) compared to removal via soil per se. Ergo, the laterite soil-pressmud-EFB mixtures signify great potential to be made as a daily cover material that minimizes heavy metals migration in landfill leachate, eliminates odor issues and providesadditional protection from further infiltration

Dam Break Analysis of Batu Dam using Hec-Ras

Dam is commonly built in Malaysia as it provides benefits to the local population, mainly agricultural activity and flood control measures. However, its massive potential energy reservoir would impose risk of sudden containment breach leading to loss of life and property at inhabited downstream area. Simulations of dam break events are crucial to characterizing and reducing threats due to potential dam failures. In all post-event natural disasters, where most structural countermeasures have been lost, the preparation of a smoother evacuation mechanism remains the most critical prevention tool for successful evacuation planning. The urgency of designing an appropriate emergency planning is important in response to the disaster. To perform a dam break analysis, hydraulic modeling is required, which involves routing the inflow flood through a reservoir, estimating dam breach characteristics, and downstream routing/modeling issues. The HEC-RAS (River Analysis System) software is commonly used for dam break studies. The software provides information on how to perform a dam break analysis, including the unique hydraulic modeling aspects that are required. Batu dam has the highest percentage of the population at risk (PAR) and most likely exposed to the flood disaster due to dam break. From flood boundary maps, it was estimated that 78% of residential areas would be affected if a dam break disaster occurs. From the simulation, the maximum depth can reach up to 18m with an estimated flow speed between 0.2 – 3m/s. At these depth and flow speed, people may lose strength and unable to control themselves in flood and would cause death and injury. Flood arrival time took 15 to 22 hours for flooding to arrive downstream with a maximum flood depth of 5.07m at Persiaran Jasa Utama and the highest depth of 12.62m at Kampung Baru Batu Caves with flood velocity between 1.60m/s to 1.46m/s. Analysis and simulation of embankment dam breach events and the resulting floods are crucial for distinguishing and mitigating dangers from potential dam failures. Accurate forecast of inundation levels and the time of flood wave arrival at downstream key places is required for the development of effective emergency response plans

Suitability of pressmud as an adsorption material in wastewater treatment and as a booster in soil fertility and productivity

Press mud is one of the most abundant wastes produced by the sugarcane industry. However, it has received far too little attention as a reactive material for pollutant removal, although its beneficial effect on soil fertility and crop productivity is well established. This paper investigates the potential of press mud to minimize heavy metal migration while boosting soil fertility and productivity. Firstly, the adsorbent was characterized by Fourier Transform Infrared Spectroscopy (FTIR) and Field-Emission Scanning Electron Microscopy (FESEM) analyses, which showed the presence of functional groups such as carbonyl, hydroxyl, and silica capable of adsorbing metal ions. The cation exchange capacity (CEC) of press mud is very high, ranging between 44.9 and 45.2 meq/100 g. Along with removal efficiency testing and evaluating breakthrough curves, characterization, and adsorption analyses (batch equilibrium and column test) were carried out. The press mud reveals promising adsorption characteristics, including a high organic content (17.62%) and the presence of carbon, which significantly affects its excellent removal effectiveness. Based on the removal efficiency test, press mud successfully removes metal ions at the highest value, such as zinc (Zn), at 99.7%. Meanwhile, its breakthrough curve reveals that it efficiently retained all heavy metals, as these metals do not reach 1 to 10 pore volumes (p.v.), indicating that press mud is a good material for heavy metal adsorption and soil productivity. This possible use establishes a new cyclical flow for the material and contributes to its minimization and reuse, adhering to circular economy ideas. However, press mud must be disposed of properly to avoid adverse effects on humans and the environment

Stormwater quality and pollution loading from an urban residential catchment in Johor, Malaysia

Sampling of urban runoff was carried out in a small catchment, which represents a residential area (3.34 ha) in Skudai, Johor. One hundred and seventeen runoff samples from ten storm events were analysed. Runoff quality showed large variations in concentrations during storms, especially for SS, BOD5 and COD. Concentrations of NO3-N, NO2-N, NH3-N, and P were also high. Lead (Pb) was also detected but the levels were low (<0.001 mg/L). In general, the river quality is badly polluted and falls in Class V based on the Malaysian Interim National Water Quality Standards. Event mean concentrations for all parameters were found to vary greatly between storms. The values (mg/L) were BOD5 (72), COD (325), SS (386), NO3-N (2.5), NO2-N (0.58), NH3-N (6.8), P (3.4), respectively. First flush phenomena were observed for BOD, COD, SS, NO3-N, NH3-N and P. The first 20–30% of the runoff volume evacuated between 20–59% BOD, 15–69% COD, 15–78% SS, 14–49% NO3-N, 14–19% NO2-N, 23–53% NH3-N and 23–43% P

Irrigation management strategies for winter wheat using AquaCrop model

Many regions of the world face the challenge to ensure high yield with limited water supply. This calls for utilization of available water in an efficient and sustainable manner. Quantitative models can assist in management decision and planning purposes. The FAO’s newly developed crop-water model, AquaCrop, which simulates yield in response to water, has been calibrated for winter wheat and subsequently used to simulate yield under different sowing dates, irrigation frequencies, and irrigation sequences using 10 years daily weather data. The simulation results suggest that “2 irrigation frequency” is the most water-efficient schedule for wheat under the prevailing climatic and soil conditions. The results also indicate decreasing yield trend under late sowing. The normal/recommended sequence of irrigation performed better than the seven-days shifting from the normal. The results will help to formulate irrigation management plan based on the resource availability (water, and land availability from previous crop)

Flood mapping using sentinel-1 SAR imagery: case study of the November 2017 flood in Penang

The Sentinel-1 SAR image by the Europe Space Agency (ESA) in the Copernicus Programme is an open source data which offers good data to develop flood inundation mapping. The flood inundation mapping is essential information for local authority personals or researchers to develop flood inventory map. The objective of this study is to develop a flood inundation mapping on November 2017 event to assess its use as potential flood inventory mapping data in Penang. The threshold method was carried out using Sentinel-1 image to extract the flood map. This method is pixel value used to separate the grey image into two parts. The flooded and non-flooded areas can be identified by separating the backscatter lower than the threshold value. The results revealed that the flood inundation maps are able to be extracted out from Sentinel-1 images

Urban stormwater quality and load estimation from urban residential area in Skudai, Johor

Sampling of urban runoff was carried out in a small catchment, which represents a residential area (3.34 ha) in Skudai, Johor. One hundred and seventeen runoff samples from ten storm events were analysed. Runoff quality showed large variations in concentrations during storms, especially for SS, BOD5 and COD. Concentrations of NO3-N, NO2-N, NH3-N, and P were also high. Lead (Pb) was also detected but the levels were low (<0.001 mg/L). In general, the river quality is badly polluted and falls in Class V based on the Malaysian Interim National Water Quality Standards. Event mean concentrations for all parameters were found to vary greatly between storms. The values (mg/L) were BOD5 (72), COD (325), SS (386), NO3-N (2.5), NO2-N (0.58), NH3-N (6.8), P (3.4), respectively. First flush phenomena were observed for BOD, COD, SS, NO3-N, NH3-N and P. The first 20-30% of the runoff volume evacuated between 20-59% BOD, 15-69% COD, 15-78% SS, 14-49% NO3-N, 14-19% NO2-N, 23-53% NH3-N and 23-43% P