x\pubyear2014\address\({}^{1}\)Dept.ofCivilandEnv.Engrg.,KongjuNationalUniversity,1223-24Cheonan-Daero,Cheonan,Korea\keywordinfiltrationstormwatermanagement;physicalclogging;sand-bottomashfilter Clogging brought mainly by the deposition and filtration of urban stormwater runoff sediments over time tend to reduce filter systems infiltration capacity that subsequently affects its lifespan and treatment capacity. The clogging rate of these systems was found to be influenced by the filter media type being used. Several types of filter media are now being utilized by which sand is the most common. Also, bottom ash is now gaining its popularity in wastewater treatment due to its high sorption capacity. In this study, a series of 1-D laboratory column experiments were conducted to better understand the filtration performance and physical clogging possibility of different sand-bottom ash filter media mixes under constant and varying head water flows. The presence of bottom ash was identified to have a significant effects in the filter systems overall performance. Noticeable amount of particle breakage brought by seepage forces to bottom ash media was made accountable for the rapid increase in the systems clogging rate. All media configurations were observed to experience premature clogging during varying head flows; whereas, complete clogging state was reached by all sand-bottom ash mixtures during constant head flows. Regardless of media mix and head condition, clogging layer was found to be mainly made-up of 100-250 m sediment size which were found to develop at the upper 15% of the filter depth. Overall, homogeneous sand filter media layer was still recommended for use as long as both filtration performance and clogging were to be considered.