Temporary Chlorination of the Martinborough water supply – FAQs

1. When was the water chlorinated?

Chlorination toook place at approximately 5.10pm, 13 May 2019.

2. What will be the impact of chlorine in the water?

The addition of chlorine to water that contains manganese, as it does in Martinborough, can cause discolouration, due to the chlorine reacting with the manganese and forming deposits in the water. 

SWDC has been doing everything possible to reduce this effect. Network pipes have been air scoured and flushed to remove any biofilm and deposits of manganese. Some people may experience a bit of discolouration initially. This should be a short-term problem.

3. Why is temporary chlorination necessary?

Community wellbeing is our number one priority. Two boil water notices have been issued for the town since the beginning of the year. This means the water needs to be temporarily chlorinated to protect the health of residents and visitors.

4. How can I get rid of the chlorine taste?

If the faint taste of chlorine bothers you, there are a couple of tricks you can use to help reduce the taste of chlorine in your drinking water. You can put the water in a container or jug in the fridge (over time the chlorine level in the water decreases) for around 48 hours or boil it. You may find that using a water filter that uses carbon filtration helps (please consult the manufacturer's instructions on recommended use).

5. So how will temporary chlorination work in the meantime without the manganese removal plant in place?

We’re confident that during the winter months we can operate with the bore that has the lowest level of manganese, which shouldn’t affect the colour of the water too much.

6. What if I get discoloured water?

Discoloured water is a possibility if there is still some residual biofilm and manganese sediment in the water pipes. The flushing and ‘air scouring’ of the water network has been completed to dislodge the biofilm before adding chlorine, but there might be some left to flush through.

Advice to households experiencing discoloured water is to run a cold tap (preferably outside tap) until the water runs clear. This will clear the discoloured water in the pipe to your property and pull in clean water from the main pipe.

If flushing a cold tap doesn’t clear the water or if you have any concerns, contact SWDC on 06 306 9611.

7. How long will the Martinborough water be chlorinated for?

This depends on the results of SWDC’s investigations into finding the source of contamination. These investigations are expected to take a number of months to complete and the town water supply will remain chlorinated during this time.

8. How likely is it that the Martinborough water supply will be permanently chlorinated?

A decision on the permanent chlorination of the Martinborough water supply has yet to be made. This decision depends on the result of SWDC’s investigations and further discussions between Regional Public Health, Lutra water consultants, and Wellington Water.

7. How will you keep us updated on the situation?

SWDC will update its website and Facebook pages on a regular basis. Information will also be shared by media - newspaper and radio.

8. What about my pet fish?

If you have fish outside in ponds you will need to either turn down in-coming water to an absolute trickle (this dilutes the chlorine level to a safe amount for your fish), or fill up drums of water and let them stand for at least 24-hours before using (the UV of the sun evaporates chlorine). For fish tanks or bowls inside, fill up a container of water and let it sit for at least 24-hours and then only replace 1/3 of this water at a time with what is in the tank already. If you’re still worried, de-chlorinating kits can be purchased from pet stores.

9. What does it mean for my water softener?

Please refer to the recommendations of the manufacturer regarding water softeners and chlorinated water. It’s possible that the filter will need to be changed/cleaned more frequently.

10. Is there any place in Martinborough to get access to unchlorinated water now?

No. If your water has a chlorine taste, try putting the water in a container or jug in the fridge (this helps the chlorine dissipate from the water). Boiling the water also helps take the chlorine taste out of the water.

 

South Wairarapa District Council