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NEA warns swimmers that waters remain too contaminated with bacterium in faeces
 FOR the third year in a row, picnickers hoping to swim in the waters off Pasir Ris Beach will be disappointed, as the area off the north-eastern shore is still too contaminated by a bacterium found in faeces to swim safely in.
The National Environment Agency (NEA) gave the water there a “fair” rating in its annual update on beach water quality yesterday, after finding too many samples containing unsafe levels of the enterococcus bacterium, which can cause gastro-intestinal illnesses like vomiting and diarrhoea if swimmers come into contact with it.
The bacterium is found in animal and human faeces, and the problem appears to be the proximity of smaller sewage treatment plants in Tampines and Changi which discharge the effluents into the area. Water treatment agency PUB said the currents off Pasir Ris Beach were not strong enough to carry the discharge out and disperse it at sea.
Some older sewage pipes may also be leaking untreated sewage.
In a study last year, the NEA also said that other sources of contamination could be moored vessels and animals in the area.
Pasir Ris has received the same rating since 2008. It may come as small comfort to know that waters there have not actually degraded, but that more stringent World Health Organisation guidelines have been in place since that year, said the NEA.
It advised the public not to swim in Pasir Ris until the next water quality review in August next year, as works are ongoing to phase out the sewage treatment facilities nearby.
Upgrading works are also being carried out to connect sewage pipes to a modern treatment facility in Changi, with its deep-water discharge pipe.
In contrast, the recreational beaches at Sentosa, Seletar Island, Sembawang Park, Changi and East Coast Park passed water quality tests with flying colours.
In water samples collected from Pasir Ris, 7 per cent contained more than 200 enterococcus bacteria per 100ml of water, exceeding World Health Organisation benchmarks.
Only beaches with not more than 5 per cent of such samples are suitable for swimming, wakeboarding and other activities involving full-body contact or immersion.
Prior to 2008, the NEA had used a different bacterium type called faecal coliforms as a water quality measure, but enterococcus was found to be a better indicator of health risks.
 At the drab and rocky Pasir Ris Beach yesterday, no one was swimming though a few people were wading.
None of the 10 beachgoers asked knew about the pollution and no-swimming advisory.
University student Lewis Tan, 20, said: “The water looks okay, but now that I know, we’re not going into the water.”
Another beachgoer, a 16-year-old student who wanted to be known only as Ashwin, pointed out that the uninvitingly murky water put people off swimming
anyway.
Dr Ole Larsen, director of the DHI-NTU research centre studying water and environment issues, noted that enterococcus was an indicator of faecal contamination.
“There are many more people in Singapore than there are wild animals, so that’s probably the best place to look,” Dr Larsen said.
He added that the highest numbers of bacteria tend to be found in sources that come from land, so sources farther offshore, such as Pulau Ubin or military training island Pulau Tekong, are unlikely to be the culprits.
PUB said it had started making plans to phase out the area’s sewage treatment
plants and mend the sewerage network in 2007.
By next year, about 23km of ageing sewers in the area will be repaired. And by 2012, the sewerage network will be extended, doing away with 39 older sewage treatment plants.
Besides the PUB measures, the NEA is also working with the Maritime and Port Authority to make sure ships moored offshore do not discharge sewage directly into the water.
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