Changes to disinfection - Sydney Water

Changes to disinfection for new water mains implementation

On Monday 23rd February we are changing the way we disinfect newly constructed water mains by replacing (in most cases) chlorination with ozone treatment.

Why are we changing? Feedback from the development industry has told us that the time taken to chlorinate, test and connect new water mains is too long and too expensive.

Watch this short video about ozone disinfection on our YouTube channel. Go to: http://youtu.be/CDjgIZzQJNA New disinfection process – takes 1 day 1. Constructors have three options for preparing new water mains for disinfection, either 

Capping/sealing of pipes and fittings: Organise for an odour and turbidity test to be carried out by listed Field Tester 

Ozone is also a more effective disinfection agent. During extensive trials, it was revealed that this method resulted in a greater pass rate than the existing chlorination method. By introducing ozone disinfection we will:

Schedule an odour and clarity test to be carried out by listed Field Tester 

Changes to disinfection| For new water mains V2.2 SW76 9/14

Option 3 Capping/sealing of pipes and fittings and swabbing for short single length water main runs (up to 18 meters in length): Schedule an odour and clarity/turbidity test to be carried out by listed Field Tester as per the nominated construction method 1 or 2 (as above).

 reduce job failure rate to less than 3%

 reduce rework (laboratory testing, labour and travel costs) and your waiting time to connect to our service.

Option 2 Capping/sealing of pipes and fittings and swabbing the water mains:

 improve employee and contractor safety, quality of the work and protect the environment

 deliver a faster, ’same day or within 24hrs’ service by supplying live, onsite results followed by connection of the new mains

Option 1

The Water Supply Code of Australia Sydney Water Edition 2014 (Particularly 15.1.1 to 15.1.4 and section 18) must be adhered to in conjunction with these options.

2. Field testers will conduct either: 

an odour and turbidity test (see option 1 above), or



odour and clarity test (see option 2 above), Page | 1

and then 

Pressure test the mains.

3. The Water Servicing Coordinator shall submit a Water Main Disinfection Notice together with the Project Validation Certificate – requesting pre-connection, disinfection and connection. The connection date must give us a minimum of 10 working days’ notice. 4. Civil Maintenance will disinfect main with ozone and take sample and receive result on site (pass/fail) 

If ‘pass’ we schedule the connection and bring the new main into service



If ‘fail’, we investigate the cause and take appropriate action.

 Important things to note: To date trials have determined that Ozone will disinfect mains that meet the criteria in the table below. This may be expanded following further testing. For all others, chlorination disinfection process.

will

remain

the

The Ozone trailer – a Joint Australian patent between Oxyzone and Sydney Water

I want to know more about…  The guideline for Capping, swabbing, flushing and testing new mains has been sent to our listed providers and will be available on our website shortly.  The ozone treatment process (Technical) – contact Peter Cresta on 9782-2344 or email [email protected]  Further enquiries or feedback contact:

Diameter of main (mm)

Maximum length of main (metres)

100

900

Or

150

400

Kathy Bain email: [email protected]

200

250

250

150

300

100

Changes to disinfection| For new water mains V2.2

Christian McNally on 8849-4042 or email [email protected]

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