How we protect our water supplies

Monitoring

• Timaru District Council regularly takes water samples to monitor microbial contents (bacteria).
• Samples are taken from the source water, treated water and from the reticulation (pipe network).
• These samples are sent to independent, accredited laboratories who analyse the results according to the Drinking Water Standards for New Zealand requirements.
• Additionally, Timaru District Council tests all water sources for a full panel of chemical determinands on a biennial (two-yearly) basis. Results of the latest chemical panel are shown below:

Comprehensive Chemical Sampling Results (September 2022)

• Comprehensive chemical sample Geraldine Temuka September 2022 (pdf, 220.2 KB updated 21-Jun-2023)
• Comprehensive chemical results Peel Forest Rangitata Huts Te Moana (pdf, 187.6 KB updated 21-Jun-2023)
• Comprehensive chemical sample Pleasant Point Seadown Timaru (pdf, 220.1 KB updated 21-Jun-2023)
• Comprehensive chemical sample Downlands incl Pareora St Andrews (pdf, 219.9 KB updated 21-Jun-2023)

Treatment

• Treatment methods vary between our different water supplies and this is because each water source is unique.
• Timaru city’s water is treated with ozone. This is a gas that dissolves in water to kill bacteria, viruses and cysts (e.g. Giardia and cryptosporidium).
• Chlorine is used in all of our potable drinking water supplies. This is because chlorine is an effective measure against contamination such as e.Coli. (Note: over 80% of the country is supplied with chlorinated water). Chlorine also continues to treat the water through our pipe network offering protection against backflow or bacteria entering through pipe breaks.
• UV (ultra violet light) disinfection is another popular treatment option which treats the water where it enters our supply network and kills giardia and cryptosporidium.
• Filtration is also used at some of our supplies. This helps with water that has high turbidity.

There are a number of other ways we protect our drinking water supplies including source protection, in river gallery filtration, and other barriers for example turbidity monitoring.

We also have a Water Supply bylaw (Chapter 15 of our Consolidated Bylaw 2018) which applies to water supplies under our care, control and management. This allows us to make and enforce rules to protect the safety of our water supplies e.g. backflow prevention. Note: water races are covered under Chapter 16.

Last updated: 23 Nov 2023