Development of rainfall-runoff modelling using the HEC-HMS at the catchment of Kelantan River, Malaysia

The simulation of rainfall-runoff is important to be analysed at the Kelantan River catchment as flood is one of the common natural disasters in Kelantan. Sustainable water management in this region is only feasible following the availability of reliable information on the rainfall-runoff and other hydrological determinants that affect the water system. This study aims to evaluate the effects of extreme rainfall on the runoff at the catchment of the Kelantan River where recurrent floods have been occurring since 1988 to 2019. The study employs the remote sensing and geographic information system (GIS) integrated with the Hydrologic Engineering Center-Hydrologic Modelling Systems (HEC-HMS) to delineate the catchment line and simulate the river discharge. The observed discharge is used during the calibration and validation process to evaluate the performance of the integrated model. The model performed satisfactorily by obtained R2 with the range of 0.80-0.97 and 0.64-0.93 in each sub-catchment during the calibration and validation period. The finding indicates that the developed HEC-HMS model has the ability to simulate event-based runoff

Integral application of electrical resistivity tomography, geochemistry and borehole data in groundwater seepage assessment

Electrical resistivity tomography (ERT) has increasingly adopted as an alternative approach in engineering, environmental and archeological studies. In the past, several limitation of conventional method in groundwater mapping was always relative to the high cost, time consuming and limited data coverage. Hence, this study adopted an ERT in order to identify the unknown problematic zone due to the excessive groundwater seepage occurrences. During data acquisition, five (five) ERT spread lines was conducted using ABEM SAS4000 equipment set. Then, field raw data was processed using RES2DINV and ROCKWORKS software to generate 2-D and 3- D of the inverse model resistivity section respectively. Engineering properties and information related to the borehole and geochemistry results was also used for interpretation and verification purposes. Geochemistry test was performed to identify groundwater sources using Atomic Absorption Spectrometer (AAS) and Ion Chromatography (IC) in order to determine the elements of cation (sodium, potassium, calcium and magnesium) and anions (chloride, bicarbonate, nitrate and sulfate) respectively. Based on ERT results, it was found that low electrical resistivity value (10 ~ 100 Ωm) which commonly associated to groundwater was detected at ground surface (0 m) until greater depth (> 10 m). Furthermore, it was found that the groundwater was classified as Ca-HCO that indicates the water was originally come from a typical shallow of the fresh groundwater. Finally, this study has successfully demonstrate that the integral application of ERT, geochemistry and borehole data was applicable to produced comprehensive outcome with particular reference to the problematic groundwater seepage assessment

Removal of Iron and Manganese Using Cascade Aerator and Limestone Roughing Filter

Combination between oxidation and filtration can be used for removing iron and manganese from groundwater especially when the concentrations of these metals were high. This study focused on the effectiveness of the cascade aerator and the size of the limestone filter media to remove iron and manganese from groundwater. Water samples used for this study were collected from orphanage home, Rumah Nur Kasih, Taiping. Universiti Sains Malaysia (USM) has provided a tube well of 15 m depth and 150 mm diameter for the orphanage home. However, the water cannot be used for domestic consumption due to high amount of iron and manganese at 6.48 and 1.9 mg/L which exceeded the drinking water standard of 0.3 and 0.1 mg/L respectively. Using laboratory physical model, the study has shown that the removals of iron and manganese have reduce the concentration until 0.17 and 0.2 mg/L respectively. Thus, the results from this study which utilize cascade aerator and limestone roughing filter could be implemented on site for the community to use the ground water for domestic purposes

Removal of Iron and Manganese Using Cascade Aerator and Limestone Roughing Filter

Combination between oxidation and filtration can be used for removing iron and manganese from groundwater especially when the concentrations of these metals were high. This study focused on the effectiveness of the cascade aerator and the size of the limestone filter media to remove iron and manganese from groundwater. Water samples used for this study were collected from orphanage home, Rumah Nur Kasih, Taiping. Universiti Sains Malaysia (USM) has provided a tube well of 15 m depth and 150 mm diameter for the orphanage home. However, the water cannot be used for domestic consumption due to high amount of iron and manganese at 6.48 and 1.9 mg/L which exceeded the drinking water standard of 0.3 and 0.1 mg/L respectively. Using laboratory physical model, the study has shown that the removals of iron and manganese have reduce the concentration until 0.17 and 0.2 mg/L respectively. Thus, the results from this study which utilize cascade aerator and limestone roughing filter could be implemented on site for the community to use the ground water for domestic purposes

Integration methods to predict the rock mechanical behavior using RocSlope

This paper proposes a method to predict mechanical failure-mechanicsm. This method is capable of predicting failure mechanism of diverse geo-hazards, such as landslides, rock slope failures, etc. The method uses the displacement or strain divergence phenomenon in the fatal phase of failure to predict failure mechanism irrespective of failure mechanism, lithology and other parameters. Using the proposed method (RocSlope), prediction of failure mechanism of case histories was done (Rock mass failure and landslides) and laboratory studies (creep tests). In most cases, safe predictions were obtained. RocSlope, is a simple, quick and reliable practical method that revealed independency to volume of failure, lithology and failure mechanism. In addition, two empirical relations to estimate the terminal phase of failure and the critical deformation rate were developed, these practical relations complement the RocSlope method. This research will analysed rock orginally from a cool temperate region in West Hokkaido,Japan was presented. A rock slope deformations of jointed-chert rock were monitored using six surface fracturedisplacement sensors. Some movements that could be related to joint growth were observed. With the RocSlope, rock mass and rock deformations were numerically analysed and joints deformations were dominantly caused by thermal fatigue. Affects of the minor freezing on deformation of rock slope can be seen were observed

Effect of Step Height On the Aeration Efficiency of Cascade Aerator System Using Particle Image Velocimetry

Aeration is an important parameter in water filtration system as it allows the transfer of oxygen to water through turbulence effect which subsequently increases air entrainment in the water. For water treatment application, aeration efficiency is measured to ensure continuous re-oxygenation of the unfiltered water. Aside from aeration, this paper also studies the flow patterns through the use of particle image velocimetry (PIV) setup. Through the use of real scale down physical model laboratory study is performed using PIV to obtain the velocity profile. These velocity profiles will then be used to calculate the aeration efficiency of the water in a cascade aerator system. Based on the findings, the aeration efficiency obtained from the PIV experiment has a maximum value at the lowest point of the cascade aerator system with a value of 0.0139 due to increase in mass flow rate as it moves through the steps with velocity of 0.418 m/s. Therefore, in the design of a cascade aerator system, it is advisable to increase the number of steps since it will increase the aeration efficiency of the system