Thursday, September 9, 2010

Beware of water quality

Annual Assessment Of Water Quality At Beaches

Singapore, 7 September 2010 - The National Environment Agency (NEA) had in August 2008 revised its guidelines for water quality for recreational use. The revised guidelines were developed based on the World Health Organisation's water quality guidelines for recreational use.

The revised guidelines are based on the microbial indicator, Enterococcus*, which corresponds better with the health risks associated with the use of recreational beach water compared to the previous indicator, faecal coliform.

Under the revised guidelines, only beaches with not more than 5% of the collected water samples having enterococcus counts of greater than 200 per 100 ml, and graded “Good” or “Very Good”, are suitable for whole–body water contact activities such as swimming, water-skiing, and wakeboarding (also known as primary contact activities). Beaches that have more than 5% of the collected samples having enterococcus counts greater than 200 per 100 ml and graded “Fair”, “Poor” or “Very Poor” are not suitable for primary contact recreation.

Water quality of Singapore beaches

In 2008 and 2009, five out of the six popular recreational beaches monitored by NEA were assessed to be suitable for primary contact activities as they were graded “Very Good” or “Good”. They are Sentosa Island, Seletar Island, Sembawang Park, Changi and East Coast Park.

The water quality at Pasir Ris beach was graded as 'Fair' under the more stringent revised WHO guidelines, and hence deemed unsuitable for primary contact activities. Accordingly, NEA has put up signages along Pasir Ris beach to advise beach goers against swimming in the water since 1 August 2008.

The NEA has now completed the annual water quality review of the six recreational beaches for 2010. Under this review, the water quality of Sentosa Island, Seletar Island, Sembawang Park, Changi and East Coast Park beaches are again graded “Very Good” or “Good”, and are suitable for primary contact activities. Pasir Ris beach continues to be graded as “Fair”. In the latest grading for Pasir Ris beach, 7% of the collected samples had enterococcus counts greater than 200 per 100 ml, compared to 8% in 2009. The public is again advised to refrain from swimming at Pasir Ris beach until the next review in August 2011.

Causes of “Fair” water quality of Pasir Ris beach

According to results from a study released by NEA in 2009 during the last annual assessment of water quality at beaches, Pasir Ris beach’s water quality is affected by various possible sources, including minor leakage from older sewers, moored vessels, animals, as well as discharges from small-scale Sewage Treatment Plants (STPs) that presently serve the more remote areas in Pasir Ris. The low water currents in the concave part of Pasir Ris beach are not effective in diluting and dispersing the discharges.

To help improve the water quality at Pasir Ris beach, PUB has an ongoing plan to extend the sewer network and phase out the 39 STPs in the Halus/Tampines, Changi and Selarang areas by 2012. PUB also has an ongoing sewer rehabilitation programme for aging sewers in this area, under which 23km of sewers will be rehabilitated by 2011. Works on the phasing out of the STPs and sewer rehabilitation are both on schedule.

NEA will continue to closely monitor the water quality at Pasir Ris beach and inform the public of the updated beach gradings in our next annual review.

(*A type of bacteria found in the faeces of human and warm blooded animals)


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For more information, please contact

Call Centre: 1800-CALL NEA (1800-2255 632)
Email: Contact_NEA@nea.gov.sg

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