The reservoir, which supplies drinking water to about 200 households, was not previously chlorinated, "as hand dosing is required in order to treat the reservoir", the council said.
All of Napier’s drinking water supply except Otatara and Puketapu had been chlorinated since May, when E. coli was again found in the system.
Faecal matter was first discovered on February 1.
* Napier City Council shuts off chlorine-free taps after E.coli detected in reservoir * Chlorine to stay in Napier water because supply is still not considered secure * Napier’s challenging year blighted by costly mistakes * Napier’s water to remain chlorinated as safety standards shift A council spokeswoman said Friday’s chlorination "was for the benefit of the Puketapu and Otatara zone".
Meanwhile, Napier residents have reported sickness and frustration over the city-wide chlorination.
Hospital Hill resident Cheri Waitoa said she was sick of the tap water.
"Now after having moved suburbs (and water supply) our tap water is so rank our cats won’t drink it – and I’ve seen the buggers drink from some manky-looking puddles before.
But I know residents in Napier, there are the odd Facebook post I see of people," she said.
Documents released to Stuff under the Official Information Act in August revealed that Drinking Water Assessors told the council in July it was failing to meet national Drinking Water Standards.
Wood revoked the council’s secure bore status, meaning the bores were not believed to be protected from contamination.