Bathing water quality
The European Union sets standards for seaside bathing water in the EU area. Although European Law is not applied directly to the Island, the Government of the Isle of Man in 1990 took the decision to adopt the same standards, namely those set out in Directive 76/160/EEC which primarily was concerned with the contamination of bathing water by sewage.
The Government Laboratory tests seawater from 19 sites around the Island for compliance with the European Union Directive concerning bathing water quality. The sites that are monitored are not necessarily all bathing beaches in the sense of being beaches where people regularly swim, with facilities to support that activity, but they are beaches from which it is known that people do bathe or participate in sports that can involve or result in immersion and possible ingestion of water.
For 20 weeks each summer season (mid May to mid September) the results of testing are plotted on a chart showing the quality of the water in a traffic-light manner as assessed to the quality standard presently applied in the Isle of Man (1976 EU Directive). This chart is updated each week during the season and is displayed at the main bathing beaches, and is also available for download. ("Bathing Water Chart 2XXX” in list of downloadable documents). In addition, although the more recent 2006 EU Directive has not as yet been adopted here, assessment is now made to this standard and a similar ‘traffic light’ chart giving weekly indications for each beach is also available for download. (Bathing Water Chart 2XXX against 2006 directive).
Any discharge or other release of untreated or only partially treated sewage to sea deposits large numbers of micro-organisms into the sea water, which have a significant influence on bathing water quality on beaches. The same is true of untreated water run-off from intensive land-based animal husbandry. These micro-organisms include bacteria and viruses, some of which can be pathogenic with the potential to cause diseases, skin irritations and gastro-enteritis. The most abundant organisms in sewage are, however, the non-pathogenic coliforms, the detection and quantification of which is the basis of the regular testing of bathing waters.
Collection of the seawater samples from the beaches is arranged by the Department of Environment, Food and Agriculture's Environmental Protection Unit (EPU). More information about the Island's water quality is available on the EPU water quality page.
The Isle of Man's sewage system has been undergoing substantial modernisation in recent years, commencing with the major 'IRIS' scheme which has effectively dealt with human sewage from the southern half of the Island since 2005, and continuing with a programme of smaller treatment works in other locations which in due course should ensure that all sewage is adequately treated. Improvements in bathing water quality have been evident in the regular monitoring data as the modernisation has progressed. It is noted, however, that not all of the beaches in the affected areas meet the best standards all the time. This may be because human sewage is not the only source of bacterial contamination, however also possibly relevant is that any incorrect sewage connections to the surface water drainage system will circumvent sewage treatment, which may be of significance particularly in locations with a substantial volume of older property. Related to this, the quality of bathing water is widely accepted as being affected by weather, with extended periods of sunny, dry weather yielding better water quality than very wet periods, due to the dual effects of ultraviolet light from the sun killing bacteria coupled with less land run-off entering the sea – so summers with good weather tend to have a higher proportion of 'good' scores than bad weather summers.
Bathing water standards
The key requirements of the 1976 EU Directive, adopted as an objective by Tynwald, relate to microbiological contamination, with mandatory limits set for total coliforms and faecal coliforms (95% of the samples taken throughout the bathing season required to have less than 10,000 total and less than 2,000 faecal coliforms per 100ml). That Directive also identifies a higher 'guideline' target standard (80% of samples having less than 500 coliforms and less than 100 faecal coliforms per 100ml). Subsequently in 2006 the EU issued a revised bathing water quality Directive which sets 3 standards instead of 2 – 'excellent' being approximately twice as stringent as the current Guideline standard, 'good' being broadly similar to the current guideline standard, and 'sufficient', a standard that sits between the current mandatory and guideline standards. The classifications are based on the last 4 years' data updated annually, not individual years, tending to average out abnormal years such as those with weather extremes affecting water quality one way or the other, though it also means that improvements such as updated sewage treatment take longer to be fully reflected in the assessment.
The newer EU standard became mandatory for neighbouring EU member states from the start of 2015. Its more stringent requirements undoubtedly impose challenges for many aiming to meet it – however it does also allow flexibility such as resampling in the event of short-term adverse weather causing a temporary worsening of water quality, which may aid compliance in some cases, subject to resources being available to do that.
Although the 2006 standard does not presently apply as an official standard in the Isle of Man, the Government Laboratory has been monitoring and assessing bathing water quality to this new standard to inform policy decisions and to enable information to be available to the public. Formal assessment to the new standard combines the data from the most recent four years, ironing out minor fluctuations arising from factors such as poor weather, thereby giving a better overall assessment of the quality of water likely to be found at the beach, although this also means that improvements arising from, for example, better sewage treatment, can take a while before they are fully reflected in the assessment. Interestingly, in common with the situation in neighbouring isles, it has been found that that whilst fewer beaches meet the new EU minimum 'sufficient' standard compared to the 1976 directive's mandatory standard, more tend to meet the next level 'good' standard than meet the 1976 ‘guideline’ target.
Other bathing water monitoring
Quite separate from the seasonal monitoring of bathing water from the sea, the Government Laboratory also undertakes bacteriological water quality testing of water taken from the various public swimming pools around the Island, including public baths and hotel swimming pools. These are variously submitted by the operator of the pool or by Environmental Health Officers, with reports given to the appropriate party.
For further details contact:
+44 1624 642250