Water quality in the River Liffey is said to be "exceptionally poor" ahead of tomorrow's 100th Liffey Swim - but the event is going ahead as planned.
Hundreds of swimmers are due to take part in the annual swimming event in the capital tomorrow afternoon - with the iconic swim this year marking its 100th anniversary.
However, Dublin City Council has advised organisers that water sample results "significantly exceed the maximum permitted levels for designated bathing waters".
They say any decision about whether the event proceeds 'is a matter for the organisers', Leinster Open Sea.
However, the group says the event will take place.
Leinster Open Sea's Brian Nolan said: "We put it back to the swimmers, and we've advised them to go to the HSE link... it's up to each individual swimmer.
"Since we put that link up, I'm after getting at least 150-200 texts of congratulations [saying] it's a great decision. So we're all looking forward to it."
Yesterday evening, Irish Water was made aware of a sewage overflow in the Knockmaroon area.
It's feared the discharge "may have been active for some days" before it was addressed.
While it has now been resolved, notices have been placed at nearby bathing locations.
Dublin City Council has notified both the HSE and the Liffey Swim organisers ahead of tomorrow's event.
They add that it's not possible to have more recent samples tested ahead of the event, and have stressed that the river isn't a designated bathing water location.
The council said: "While any decision in relation to this event is a matter for the organisers, it is noted that a number of tidal cycles will have taken place prior to the Liffey Swim and that, as is done every year, the ESB will increase flows in the Liffey prior to the event to further dilute any residual contaminants.
"It would, therefore, be hoped that the river water quality will have improved significantly by the time of the event but, unfortunately, no guarantees can be given in this regard."
The council adds that it regrets the situation "given the long history" of the Liffey Swim.
In a statement this evening, the HSE said it was informed of a significant increase in bacteria in the Liffey between Glenaulin Park and East Link Toll Bridge .
The executive is warning that swimming in the water may cause illness.
They've offered the following advice:
- Avoid swimming or other water activities in the River Liffey if you are pregnant or have a weakened immune system.
- Avoid swallowing or splashing water as much as possible.
- Avoid swimming or other water activities with an open cut or wound – if you have one, make sure it is covered appropriately.
- Wash your hands before handling food.
- Shower after swimming or water based activities.
Anyone who does feel ill after swimming in the Liffey is being told to seek medical advice and inform doctors that they were in the water.