Permeable concrete is used to reduce local flooding in urban areas. However, it is prone to clogging
by particulate matter and requires regular maintenance. This paper reports on the performance of
permeable concrete exposed to different clogging test methods to further understand this complex
phenomena. New methods were developed to study the clogging effect and to define a clogging
potential. The tests involve applying flowing water containing sand and/or clay in cycles through
the sample and measuring the change in flow rate. Clogging depends on the applied solution and
exposure method used. Significant permeability reductions were observed in all samples,
particularly when simultaneously exposed to sand and clay. This is because flocculated clay
adhered to surface of sand particles and this caused increased clogging.