In this study, we discuss the hydrodynamics of the modular concept of a well known wave energy device - the Oscillating Wave Surge Converter. Such a concept has emerged to address some of the shortcomings in the original design of the device. A mathematical model is presented to analyze the effect of the interactions of the system. The analysis is performed with a modular system comprising of six identical modules of total combined width 24 m, reminiscent of the Oscillating Wave Surge Converter - Oyster800 developed by Aquamarine Power. Various design strategies are explored. It is shown that such a closely packed system of modules results in multiple resonances which can potentially be exploited to capture more power. It is also observed that the modules lying at the center of the system capture more energy than those lying at the edges. An optimization of power take-off system shows that at lower wave periods it is possible to capture the levels of power similar to those of an equivalent size rigid flap while at higher periods, the modular system has the potential to capture more energy due to the occurrence of multiple resonances.