Source: New Zealand Herald, 25 January 2018
Christchurch's water will be
temporarily chlorinated to prevent the risk of it becoming
City councillors voted on
Thursday after a lengthy and at times fiery discussion to
chlorinate its 56 pump stations until work has been done to make
all its wells secure.
City councillors Sara
Templeton, Aaron Keown and Mike Davidson voted against temporary
chlorination because the risk was low, and they wanted the public
to make the decision.
They received applause from
the public gallery, but were outvoted.
City councillors made it clear
they did not want permanent chlorination after the upgrades are
The chlorination will take 60
days to start. It will cost $600,000 to do, as well as $20,000 a
month in operating costs.
In December, the city lost its
secure bore status because assessments found 103 below-ground
wellheads were not sufficiently sealed to prevent surface
groundwater contamination, especially in heavy rainfall.
City council staff and medical
officials found out on December 22. Mayor Lianne Dalziel and
elected members were not aware until January 15.
A work programme is under way
to upgrade city council wells by December.
In a separate motion, city
councillors unanimously voted to accelerate the programme, costing
The water would be chlorinated
until the city got back to "secure" status, which is hoped to be
done by October.
They also asked for a report,
through the infrastructure, transport and environment committee, on
any additional costs, and an external review by chief executive
Karleen Edwards about the whole situation.
It is currently safe to drink
the water - the risk is the chance of future contamination.
Cr Jamie Gough said to keep
Christchurch water chlorine free in the future, they needed to do
it temporarily now.
In September 2016 the city
council went against staff advice and decided not to temporarily
chlorinate the water in the northwest of the city, while it
upgraded its shallow bores.
Ms Dalziel said she was not
prepared to take the risk this time.
"If you look at Havelock
North, three to five people died and there were thousands infected.
There would be hundreds or thousands potentially exposed here."
Cr Templeton asked if Medical
Officer of Health Alistair Humphrey would have preferred the water
be chlorinated last month when the risk was discovered.
Dr Humphrey said yes but there
had not been a large risk because of the delay.
Cr Templeton also questioned
the timeliness of the response, but was shut down by Ms
"There's an assumption there
has been a delay in response. This is the first council meeting of
the year so there hasn't been a delay in response," Ms Dalziel
"Council staff have had
delegation on this matter, so they relinquish that this week. I
just want to put that to bed."
Cr Yani Johanson and Ms
Dalziel asked why the wellheads now did not meet standards when a
number of them were upgraded following the February 22, 2011
"I think we do have to look at
the quality of the work [inspections] that was undertaken before,"
Ms Dalziel said.
Additional funding may be
required to accelerate the upgrade programme. But it was not yet
known how much.
It would be found within the
existing maintenance budget. Other things with lesser importance
may be deferred.
Dr Humphrey said the city
council went above and beyond to keep the water safe.
The city council chlorinated
the water following the February 22, 2011 earthquake, he said.
Dr Humphrey could have ordered
the city council to chlorinate the water under the Health Act, had
the vote gone the other way.
The decision comes after a
Government inquiry into the 2016 Havelock North contamination
recommended all reticulated drinking water in the country be
The outbreak caused more than
5000 people to become ill with campylobacteriosis, with about 45
hospitalised. It was linked to four deaths.
Dr Humphrey said there was no
evidence chlorine at levels put in drinking water caused any health