An integrated, online fouling monitoring technique that provides dynamic and real-time information of membrane fouling during a water treatment membrane process was developed. This technique has preliminarily been demonstrated for monitoring particulate fouling in a water treatment microfiltration process using a single photo sensor. The results of the online dynamic analysis suggest that this technique provides in situ measurement of fouling layer thickness, dynamic analysis of the fouling layer structure, and monitoring of water quality during the membrane filtration process.