Come on in, the water’s... free of E-coli

Irish scientists develop test to check sea’s swimming quality

FAST-RESULT E. coli tests could soon be available to swimmers to allow them to swim safely all year round.

Scientists in Dublin City University have developed a tool that would allow bathing waters to be tested for bacteria such as E. coli rapidly and regularly.

Housing and Local Government Minister Darragh O’Brien has said he has asked the Bathing Water Expert Group to consider giving fast-result E. coli test kits to swimming and water sports groups to avoid the standard 18- to 36-hour wait for full lab results.

It comes as demand for all-year swimming grows.

At present, there’s only a requirement to monitor water quality during the bathing season – from June to mid-September.

While some local authorities continue testing throughout the year, there are concerns that less regular testing during ‘off season’ can leave people vulnerable to bacteria when swimming – especially now that many people go swimming no matter what the weather is like.

The Bathing Water Expert Group is currently investigating the ‘national appetite’ for increased testing and resources to facilitate year-round swimming, Local Government Minister Darragh O’Brien has said.

And DCU scientists are developing an automated E. coli testing system which could allow bathers to swim safely out of season.

Green Party councillor and year-round sea swimmer Donna Cooney has told how she knows of swimmers who have become violently ill after swimming in untested water with sewage borne-bacteria such as E. coli.

Director of DCU’s Water Institute and Professor in Chemistry, Fiona Regan said it is down to county councils as to whether they will test year-round, with some councils monitoring more often than others.

However, since weather patterns are changing due to climate change, heavy rainfall can lead to storm water overflows at watertreatment plants at capac round ity. To override this, effluent is sent directly out.

‘That can happen at any time and I suppose in the winter-time we’re worried less about that happening or at least we report it less, because we don’t need to monitor,’ she said.

Prof. Regan said this needs to be monitored year-to ensure the ‘swimability’ of the water.

‘For compliance, we need to have the numbers of bacteria in the water, that’s the information that is needed to send back to Europe.

‘However, for swim-ability, we need to check the water every day. So, we’ve developed a sensor called ColiSense, which does not measure the numbers of E. coli formed but it tells us the likely concentration.’

This system would allow quick testing for E. coli in sea water.

‘We can take a sample in the morning from the bathing area, we filter the sample, we add reagent. We wait a short time, within an hour-and-a-half, and we have our reading.

‘That reading can then be pinged using wi-fi to a board along the beach where you can say it’s safe to swim,’ said Prof. Regan, adding that this process can be automated. ‘There are technologies out there that can be positioned at a swimming area, and they can take a number of samples. You could have an automatic sampler.

‘We’re in the process of trying to commercialise this, so we’re looking at what we call near real-time.’

Prof. Regan said there is no reason why this system couldn’t do multiple samples in a day because experts would say that the condition of the water changes, which might alter the recommendation as to whether people should swim or not.

The system has been tested in Fingal, Dún Laoghaire and Waterford and it is in the process of being commercialised.

Prof. Regan said they are looking to begin with a 12month pilot programme.

‘Need to check every day’