Before the start of the bathing season, Member States shall notify the Commission of (a) all waters identified as bathing waters, (b) the reasons for any change compared to the previous year. Spatial data is aligned with the provision of protected areas under the Water Framework Directive. Data on the water quality of each swimming pool are provided. Values of quality class ("qualityClass"): 1 - excellent quality 2 - good quality 3 - satisfactory quality 4 - poor quality. 0 - means that there is no rating yet, because the rating is based on the results of 4 seasons, it is either a new swimming pool, or there was a season when the swimming pool was not used for some reason.