Gisborne District Council has had to open the emergency sewer valve on Oak Street into the Taruheru River. Photo: Supplied / Gisborne District Council
Contractors are still working to clear garden waste from a sewage pipe in Gisborne's suburb of Mangapapa, but say an emergency overflow valve is now shut off.
The council opened the valve into the Taruheru River last night after sewage spilled from a manhole on Dalrymple Road.
Council spokesperson Dave Hadfield said the valve was shut off at 5.30am and that the blocked pipe was being cleared 150m at a time.
Cameras would be going into the the network later today and water quality testing would begin, he said.
A ban on swimming and fishing at Gisborne's rivers and beaches was expected to remain in place for the next five days.
A council Facebook post on Monday hit out at whomever had been responsible for the act.
"For goodness sake, please take your greenwaste to the transfer station or hire a wheelie bin - don't dump it down a manhole or chuck it down a riverbank even," it said.
The pipe was blocked with garden waste, and caused wastewater to back up and manholes to start popping - coming at a time when the network has just recently dealt with heavy rain, it said.
It was especially disappointing that this had happened at a time that water users like Waka Ama were training for the national competitions, Hadfield said.
It was frustrating that people were deliberately disposing of greenwaste irresponsibly, he said.
"It's actually a deliberate act to cut, you know a size of a manhole is quite small, but to deliberately cut branches to that size so you could fit it in is a deliberate action, that's what we're so disappointed about."
While an initial blockage was cleared on Monday evening, Hadfield believed there could be multiple blockages in up to 500m of sewer pipe in the Mangapapa area.
It could be difficult to find the people responsible as there were many manholes on private property in the area affected, Hadfield said.
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