Seasonal variations in faecal indicator bacteria concentrations and weather influences on bathing water quality

Here in Northern Ireland monitoring of identified bathing water sites for faecal pollution falls under the EU Bathing Water Directive (2006/7/EC). The enumeration of faecal indicator bacteria (FIB) is utilised to identify the potential risk from faecal pathogens to the public. In this study we investigated the seasonal variations and weather influences on FIB in Newcastle, County Down. Water samples were collected over a year from eight sites, two marine and six fresh water within the catchment. Samples were filtered through cellulose nitrate filter membranes using an adapted method from ISO-7899-2 for the enumeration of intestinal enterococci and The Standing Committee of Analysts Method for enumeration of Escherichia. coli. Environmental data including 24-hour rainfall and temperature was recorded from the MET Office. In this study, we found that there is a significant correlation between the concentration of FIB and the season and weather, highlighting the influence weather can have on the quality of bathing water.