Open water swimming (OWS) refers to swimming in waters such as the sea, lakes, rivers, reservoirs or canals. OWS is becoming increasingly popular in Ireland, in particular in association with triathlon. As the summer approaches increasing numbers of people will take to our open waters to train, participate in events, or simply for recreation.

Open water swimming can have great benefits for physical, mental and social health. However, open waters are at risk of pollution, resulting in a risk of infectious diseases for swimmers. There is a particular risk of gastrointestinal disease from OWS due to pollution with sewage or animal faeces. Animal faecal contamination can be from a number of sources: agricultural run-off from fields which have been sprayed with slurry; birds, livestock or domestic animals defecating in or near waters. Water can be contaminated with sewage due to: poorly located or poorly maintained septic tanks; wastewater system failures; or direct discharge of sewage from wastewater plants. Water is at particular risk of being of poor quality during and after heavy rainfall as run off rainwater from agricultural or urban areas can be contaminated. The activation of storm overflows to prevent flooding, during periods of heavy rainfall can also lead to contamination of water.

In Ireland, the 2008 Bathing Water Quality Regulations aim to improve the quality of bathing water and minimise the risk to swimmers. Only ‘identified’ bathing waters are subject to these regulations. These are waters which have been identified by local authorities as being widely used by the public for bathing, and are monitored, managed and assessed as per the regulations. Under the regulations, local authorities must assess the water quality of these waters at least four times during the bathing season which runs between 1 June and 15 September. Many local authorities will sample more frequently than this. The local authorities must notify the Environmental Protection Agency (EPA) and the HSE about any incidences which have or could adversely impact on bathing water quality and on the health of bathers, inform bathers of any risk, and implement measures necessary to eliminate or reduce the risk. A guide on how the HSE respond to bathing water incidents is available here.

Information on identified bathing waters around Ireland can be found on the Splash website (splash.epa.ie). Here you can view the profile of all identified bathing waters, the latest bathing water quality results, and information on any current incidences. Bathing water incidents will also be reported by the EPA via their twitter account (@EPABathingWater), and on local authority websites.

All open waters, even identified bathing waters, can be subject to transient pollution, for example after heavy rain as described earlier.  Whether swimming in identified bathing waters or in other open waters, swimmers should follow the following recommendations to minimise the risk of infectious diseases:

• When planning your swim:
  • Check the noticeboard at the bathing spot, the SPLASH website, or the relevant local authority website to ensure there are no current incidences
  • Avoid swimming after heavy rainfall
  • Avoid swimming in water that looks dirty
  • While swimming:
    • Cover cuts or wounds with waterproof plasters
    • Avoid splashing water into your mouth or swallowing water
    • Consider wearing appropriate protective clothing such as a wetsuit, gloves or protective footwear
    • After swimming:
      • Clean hands with soap and water as soon as possible after leaving the water, and before eating or drinking
      • Clean any cuts or wounds with soap and water
      • Rinse any swimming equipment, bathing suits or wetsuits with clean water as soon as possible after leaving the water and clean as per the manufacturers’ instructions
      • Clean hands with soap and water after handling swimming equipment, bathing suits or wetsuits
      • If you are concerned about any symptoms which develop after swimming, seek medical assistance and inform the medical practitioner that you have been in open water
      • If you develop diarrhoea, avoid swimming in the open water or pool for 48 hours from the time symptoms resolve

 
Eve Robinson, HPSC