06 Nov Cemaes Bay moves into compliance for the first time in three years

We are delighted to say that Cemaes Bay has achieved compliance with the EU Directive in 2018.  The modelling system provided by the Acclimatize team is not required under EU legislation, but its use will enhance the bathing experience of visitors to Wales and add resilience to the local economy, which is heavily reliant on visitors to the Welsh coastline and its bathing waters.

Cemaes Bay was the first site sampled by the Welsh team working on the Acclimatize project during the 2017 bathing season.  This effort has resulted in: (i) a quantitative source apportionment of faecal indicator bacteria movement into the bathing water (see Cemaes QMSA comp 05_11_18.pdf); and (ii) a predictive model used to drive advisory signage at this site, which had failed the EU Bathing Water Directive (2006) in 2016 and 2017.  The new model was calibrated using half hourly sampling for 12 hours during 60 bathing season days in 2017.  This gives accurate prediction of water quality at the bathing water, with explained variance over 70%, using hydrological, tidal and meteorological predictor variables.  Model predictions (blue line) and actual 2017 data (orange circles) are presented in Figure 1 below.  Importantly, the high bacterial counts responsible for beaches failing Directive standards are correctly predicted by the new modelling system provided by the Acclimatize project.  This allows such ‘at-risk’ bathing waters, with a history of non-compliance, to be more resilient to natural causes of poor water quality such as rainfall events.

Figure 1: Prediction of Water Quality at Cemaes Bay bathing water in Anglesey, Wales (Click on image to enlarge)

To view the full presentation, click here Cemaes QMSA comp 05_11_18