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WEDNESDAY, JULY 6, 1994
MEASURES TO TACKLE DISCOLOURED TAP WATER
THE WATER SERVICES DEPARTMENT (WSD) IS TAKING ACTION TO THE WATERWORKS REGULATIONS TO BAN THE USE OF UNLINED GALVANISED PIPES WHICH ARE PRONE TO RUSTING AND CORROSION.
AMEND IRON
PUBLIC'S
IN ADDITION, WSD HAS ALSO TAKEN MEASURES TO FURTHER REDUCE MANGANESE CONTENT IN THE FINAL TREATED WATER IN VIEW OF THE CONCERNS ALTHOUGH THE CONCENTRATION LEVEL HAS NO ADVERSE HEALTH.
EFFECT
THE
ΤΟ
IN
THIS WAS STATED BY THE SECRETARY FOR WORKS, MR JAMES BLAKE,
REPLY TO A COUNCIL TODAY (WEDNESDAY) IN A WRITTEN LEGISLATIVE QUESTION BY THE HON EMILY LAU.
THE
MR BLAKE SAID THE "YELLOWISH" TAP WATER WAS FOUND TO BE BY SLIGHTLY HIGH IRON AND MANGANESE CONTENT.
CAUSED
CORRODED PIPES IN THE CONSUMERS' PREMISES COULD BE A SOURCE FOR THE IRON CONTENT.
1 RON NORMAL TREATED WATER ALSO CONTAIN SMALL QUANTITY OF
AT ACCEPTABLE LEVELS AS LAID DOWN BY
WORLD THE
AND HEALTH
MANGANESE, ORGANISATION.
SUCH IRON AND MANGANESE MAY, THE DISTRIBUTION
SYSTEM
AS
IN THE COURSE OF TIME, DEPOSIT
THE WELL AS
WITHIN PIPES
CONSUMERS'
IN
PREMISES.
THE
DISCOLOURATION
OF
SUCH
COULD BE CAUSED BY DISLODGEMENT DEPOSITS, WHICH MAY HAVE BEEN INDUCED BY CHANGES IN VELOCITY, PRESSURE OR DIRECTION OF FLOW OF WATER IN THE WATER MAINS.
AS
THE LONG AS
LEVELS OF IRON AND MANGANESE ACCEPTABLE LIMITS, ADVERSE EFFECTS TO HEALTH ARE UNLIKELY.
FALL
WITHIN
MR BLAKE NOTED THAT COMPLAINTS ABOUT DISCOLOURED TAP WATER WERE MOSTLY RECEIVED IN MAY THIS YEAR.
TOOK WATER SYSTEM
UPON RECEIPT OF THESE COMPLAINTS, WSD IMMEDIATELY SAMPLES FROM THE COMPLAINANTS' PREMISES AND THE NEARBY SUPPLY FOR ANALYSIS.
IN MOST CASES, THE WERE WITHIN
IRON LIMITS.
THE RESULTS OF SUCH ANALYSIS INDICATED THAT
MANGANESE CONTENT IN THE SAMPLES AND
ACCEPTABLE
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