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The impact of floods is the most severe among the natural calamities occurring in Malaysia. The knock of floods is consistent and annually forces thousands of Malaysians to relocate. The lack of information from the Ministry of Environment and Water, Malaysia is the foremost obstacle in upgrading the flood mapping. With the expeditious evolution of computer techniques, processing of satellite and unmanned aerial vehicle (UAV) images for river hydromorphological feature detection and flood management have gathered pace in the last two decades. Different image processing algorithms—structure from motion (SfM), multi-view stereo (MVS), gradient vector flow (GVF) snake algorithm, etc.—and artificial neural networks are implemented for the monitoring and classification of river features. This paper presents the application of the k-means algorithm along with image thresholding to quantify variation in river surface flow areas and vegetation growth along Kerian River, Malaysia. The river characteristic recognition directly or indirectly assists in studying river behavior and flood monitoring. Dice similarity coefficient and Jaccard index are numerated between thresholded images that are clustered using the k-means algorithm and manually segmented images. Based on quantitative evaluation, a dice similarity coefficient and Jaccard index of up to 97.86% and 94.36% were yielded for flow area and vegetation calculation. Thus, the present technique is functional in evaluating river characteristics with reduced errors. With minimum errors, the present technique can be utilized for quantifying agricultural areas and urban areas around the river basin.

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The behaviour of river can be perceived by analysing the sediments to a substantial extent. Computation of sediment weight per unit volume of water, sediment distribution along the quantifiable parameters of water body and mensuration of amount of useful as well as detrimental contents of sediments entails for sediment water sampling. The design and outline of an effortless and uncomplicated water sampler is presented in this paper. Although a number of manual, semi-automatic and fully automatic samplers are in attendance, there is a gap in asking price of previously available samplers and the present tool. The cost of sampler can be limited by designing for its specific purpose. The present sampler can only be used for top layers of water body ( < 5 feet). But the same sampler can be modified for collection up to 10 to 15 feet. Design stresses of materials and force acting on the sampler is used to examine the safety of components used at the critical points. Manual design calculations and experimental use of the instrument in Kerian River, Malaysia evinces the approval of the design. The trouble-free design and facile use of the device will assist in suspended water monitoring for research in an economical way.