An important point of attention in the research is that this has hardly fallen any rain during the measurement period, so that no extra pollution was caused via sewer overflow. Those unusually dry weather conditions can make the results seem more positive than the actual average state.
The analysis of the samples was subdivided into four quality levels: very good, good, acceptable and bad. The Heulebeek in Gullegem is an example of a watercourse with poor water quality, while the Schonebeek in Wevelgem is assessed as very well.