To set up and visualize the flushing frequency, a graph based on the average of the NaCl canal measurements was created (Fig. 10). Calculating the graph, a flushing schedule was created. Particularly for when only canal water is used. It can be concluded that the system should be flushed every second week, with a fixed quantity of 20% being taken out each time. The 20% are in this case replaced by less canal water. However, the frequency of rainwater usage can delay the flushing process.