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Here are some common questions asked regarding water quality.
In rare instances,dissolved air in tap water may appear as tiny bubbles making it milky or cloudy. Similar to dissolved gas in carbonated and fizzy drinks, these bubbles are much smaller and will disappear after a few minutes. While this may affect the appearance of the tap water, water is still safe for consumption.
Should the issue persist, please call PUB’s hotline at 1800-CALL-PUB for assistance.
The first thing that customers can do is to run their taps and flush any water tanks inside their premises until the water runs clear. While doing so, avoid using the water for laundry or any other purposes. If the water has not cleared up after 10 to 15 minutes, customers can call PUB’s hotline at 1800-CALL-PUB for assistance with their water supply.
Customers should also try to determine the source of the discoloured water. For example, is the discoloured water only localised to a single appliance or from the hot water taps/showers? If it is, this could indicate a faulty hot water heater or appliance.
We will investigate and determine the likely cause and source of the discoloured water within PUB’s water mains. Depending on our findings, we will conduct emergency pipeline operations and isolate the source to prevent further discolouration.
If the discolouration comes from PUB’s water mains, temporary water supply, such as water bags, will be provided for the customers affected. In more serious cases, water wagons will be deployed. To clear brownish water from PUB’s water mains, our officers will flush the water containing re-suspended mineral sediments out from the water mains in a controlled manner until the water clears up.
However, if the source of discoloured water is within the customer premises (E.g. faulty or corroded water tank), we will advise the customer to rectify the problem by replacing or repairing the appliances or pipes.
As discoloured water can occur as a result of internal fittings, customers can do their part by ensuring that corrosion resistance materials are used for their service pipes. Customers should also frequently check that their appliances are in good working condition and replace them when there are signs of corrosion or when it has passed its service life stipulated by the supplier.
The common cause for temporary discolouration of your tap water is due to the re-suspension of mineral sediments inside the pipe. These sediments form over time when naturally-occurring minerals in tap water settle at the bottom of the pipes, especially when the water in the pipes is slow-moving. Discolouration could have also been caused by other issues and if you do observe discolouration in the water, please let the tap run until it is clear before drinking the water. If the water has not cleared up after 5 to 10 minutes, customers can call PUB’s hotline at 1800-CALL-PUB for assistance with their water supply.
Feedback on discoloured water will be investigated thoroughly to establish the cause and ensure that PUB’s water supply is clean and clear. We also work very closely with our customers, Town Council and Building Maintenance Team to ensure that the water is fit for potable use within WHO guidelines.
PUB engineers study and operate the water distribution network carefully during emergency and maintenance pipeline operations to prevent sudden changes in flow direction. This helps to minimise discoloured water incidents.
We also engage the Town Councils and SCDF regularly to ensure that their maintenance operations are conducted with care to minimise discoloured water incidents. In addition, PUB send out an annual circular to Town Council, Management Corporation Strata Titles (MCSTs) and building owners of their responsibility to ensure the proper security and maintenance of their water service installations including their potable water storage tanks.
Customers could also play their part by paying attention to their service pipes and appliances and ensure they are in good working condition. If water in their service pipes or water heater has been stagnant for a long period of time, they should flush before using the water, especially for potable use.
Do you wonder why filter devices (or cloth filters at the taps) turn brown? These brownish deposits are due to the minute amounts of minerals inherent in the water supply that were absorbed and oxidised over time. Filters may become a breeding ground for bacteria if they are not cleaned or replaced regularly.
These minerals are also common causes of water discolouration, when re-suspension occurs due to sudden flow changes in the water pipe. Essential maintenance operations such as the routine cleaning of water tanks, flushing of watermains and service pipes in buildings may cause re-suspension of mineral sediments. However, discoloured water can also be attributed to stagnant water in service pipes and water service installations as a result of infrequent use.
PUB has implemented fluoridation of drinking water as part of our water treatment process since 1957. This is a requirement by the Ministry of Health (MOH) to prevent dental cavities.
The fluoride levels in Singapore’s drinking water are lower than the maximum level of 0.7 mg/L stipulated in the Environmental Public Health (Water Suitable for Drinking) (No.2) Regulations 2019 and is well within World Health Organisation's guideline of 1.5 mg/L.
In rare instances,dissolved air in tap water may appear as tiny bubbles making it milky or cloudy. Similar to dissolved gas in carbonated and fizzy drinks, these bubbles are much smaller and will disappear after a few minutes. While this may affect the appearance of the tap water, water is still safe for consumption.
Should the issue persist, please call PUB’s hotline at 1800-CALL-PUB for assistance.
The first thing that customers can do is to run their taps and flush any water tanks inside their premises until the water runs clear. While doing so, avoid using the water for laundry or any other purposes. If the water has not cleared up after 10 to 15 minutes, customers can call PUB’s hotline at 1800-CALL-PUB for assistance with their water supply.
Customers should also try to determine the source of the discoloured water. For example, is the discoloured water only localised to a single appliance or from the hot water taps/showers? If it is, this could indicate a faulty hot water heater or appliance.
We will investigate and determine the likely cause and source of the discoloured water within PUB’s water mains. Depending on our findings, we will conduct emergency pipeline operations and isolate the source to prevent further discolouration.
If the discolouration comes from PUB’s water mains, temporary water supply, such as water bags, will be provided for the customers affected. In more serious cases, water wagons will be deployed. To clear brownish water from PUB’s water mains, our officers will flush the water containing re-suspended mineral sediments out from the water mains in a controlled manner until the water clears up.
However, if the source of discoloured water is within the customer premises (E.g. faulty or corroded water tank), we will advise the customer to rectify the problem by replacing or repairing the appliances or pipes.
As discoloured water can occur as a result of internal fittings, customers can do their part by ensuring that corrosion resistance materials are used for their service pipes. Customers should also frequently check that their appliances are in good working condition and replace them when there are signs of corrosion or when it has passed its service life stipulated by the supplier.
The common cause for temporary discolouration of your tap water is due to the re-suspension of mineral sediments inside the pipe. These sediments form over time when naturally-occurring minerals in tap water settle at the bottom of the pipes, especially when the water in the pipes is slow-moving. Discolouration could have also been caused by other issues and if you do observe discolouration in the water, please let the tap run until it is clear before drinking the water. If the water has not cleared up after 5 to 10 minutes, customers can call PUB’s hotline at 1800-CALL-PUB for assistance with their water supply.
Feedback on discoloured water will be investigated thoroughly to establish the cause and ensure that PUB’s water supply is clean and clear. We also work very closely with our customers, Town Council and Building Maintenance Team to ensure that the water is fit for potable use within WHO guidelines.
PUB engineers study and operate the water distribution network carefully during emergency and maintenance pipeline operations to prevent sudden changes in flow direction. This helps to minimise discoloured water incidents.
We also engage the Town Councils and SCDF regularly to ensure that their maintenance operations are conducted with care to minimise discoloured water incidents. In addition, PUB send out an annual circular to Town Council, Management Corporation Strata Titles (MCSTs) and building owners of their responsibility to ensure the proper security and maintenance of their water service installations including their potable water storage tanks.
Customers could also play their part by paying attention to their service pipes and appliances and ensure they are in good working condition. If water in their service pipes or water heater has been stagnant for a long period of time, they should flush before using the water, especially for potable use.
Do you wonder why filter devices (or cloth filters at the taps) turn brown? These brownish deposits are due to the minute amounts of minerals inherent in the water supply that were absorbed and oxidised over time. Filters may become a breeding ground for bacteria if they are not cleaned or replaced regularly.
These minerals are also common causes of water discolouration, when re-suspension occurs due to sudden flow changes in the water pipe. Essential maintenance operations such as the routine cleaning of water tanks, flushing of watermains and service pipes in buildings may cause re-suspension of mineral sediments. However, discoloured water can also be attributed to stagnant water in service pipes and water service installations as a result of infrequent use.
PUB has implemented fluoridation of drinking water as part of our water treatment process since 1957. This is a requirement by the Ministry of Health (MOH) to prevent dental cavities.
The fluoride levels in Singapore’s drinking water are lower than the maximum level of 0.7 mg/L stipulated in the Environmental Public Health (Water Suitable for Drinking) (No.2) Regulations 2019 and is well within World Health Organisation's guideline of 1.5 mg/L.
