Wen Kam Leong, Alex Lung Keat Ngo, Alvin Choon Hsien Wong, Jen Hua Ling and How Teck Sia 2022. The Mandatory 4 Years Desludging Frequency of Underground Septic Tanks in Residential Areas: A Case Study in Sibu Sarawak, East Malaysia. Journal of the Civil Engineering Forum. 8, 2 (May 2022), 147-156. DOI:https://doi.org/10.22146/jcef.3812.