Council’s water standards are considerably higher than the 76 percent compliance reached in many parts of the country, scoring 99.8 percent compliance in the Annual Report 2016-17.
All Whangarei’s seven water treatment plants have ultra violet treatment and chlorination to destroy pathogens. Five have additional clarification and filtration systems.
All are capable of fully complying with the requirements set under the standards and most exceed them. However, even with all the treatment processes, problems can still occur.
Whangarei Water Services Manager Andrew Venmore said there had been recent reports of a musty, earthy smell coming from tap water in some parts of Bream Bay.
“The water was (and is) perfectly safe to drink, it contains no bacteria or harmful substances. But, the treatment process does not remove odour and people, understandably do not like the taste.
“To address this, we have changed where we are getting the water from and have flushed the pipes that contained this water. Anyone who is still smelling earthiness in their tap water should run the tap for a while (save it for watering plants) and call us if it has not cleared. We want to stay on top of this issue.”
Mr Venmore said the smell was caused by dissolved organics in the raw water. It is likely that the hot weather has resulted in water containing organics rising to the surface of the Wilsons Dam and being drawn into the treatment plant.
In the meantime, he urged people on tank, bore, stream or other private water supplies to keep a close eye on the safety of their tap water.
Laboratory Manager Lois Howe said “between 1 July 2016 and 30 June 2017, WDC Laboratory tested 707 private water supplies from roofs, streams, bores and springs in the District.
“Of those, 288 contained E coli (40.7%). These results included samples from people considering potential alternative supplies, as well as existing home supplies.
“We do testing for some community supplies (schools, rural play centres) and irrigation schemes. Of 215 samples of this sort 17 contained E coli (7.9%) and were reported to Ministry of Health as required.
“When contamination is identified, we refer our customers to Ministry of Health guidelines, their plumber or water treatment supplier for advice.”