A flow imaging and monitoring system for synchronized management of wide area drainage that includes an interposer for supporting monitoring and management equipment in a manhole, a module for illuminating water flowing in pipes at the base of the manhole, a module for monitoring responses to reflected light, a sealed and rechargeable battery pack, and a data analysis and management system to interpret data streams in real time. The interposer can be adjusted to fit the diameter of the manhole and can be adjusted to be placed under the manhole cover. The module for illuminating the flowing water can be adjusted to generate various frequencies. The support structures for the modules can be adjusted for varying pitch, roll and yaw with respect to the manhole. The data analysis and management system is supported by cloud computing.