Marine pollution comes from different sources including agricultural, industrial, and domestic wastewater discharge from human activities in coastal areas. Environmental simulation can represent ground and sea characteristics, modeling spreading occurring in both spaces. These characteristics are variable, due to soil capability and reaction, and sea behavior, in particular currents and tides. This work presents a heterogeneous tiling approach modeling sea behaviors in coastal areas based on tidal currents and ground effects.  The ground is segmented into irregular cells following administrative divisions for collecting observations while the sea area is segmented into regular geographical tiles. The impact of the interactions is represented by messages carrying qualities and quantities of physical pollution. Channels link cells following cellular automata or distributed system paradigms. This system architecture allows to produce a synchronous message passing program suitable for massive parallel execution. The status of cells and messages are produced step by step and can be interpreted graphically. Green tides caused by eutrophication appear when nutrients circulate in high concentrations in coastal waters. These nutrients come from land use, accumulate, and propagate to the shores mainly through rivers end up joining the sea or the oceans. Our simulations show when and where tides are able to increase concentration levels, producing space and time characteristics.