Napier City Council says it is satisfied with the efficiency of water drainage after the deluge. Photo / Warren Buckland
Napier City Council says it is satisfied with the efficiency of water drainage after the deluge. Photo / Warren Buckland
Napier City Council says it's "pleased" with the efficiency of flood drainage, despite pumps briefly stopping due to a power outage and a quarter of a sewer pump station being inundated by floodwater.
"This was a one-in-250-year event which would have exceeded the networks of every New Zealand council, regardlessof the standards they were built to," a spokeswoman said.
After heavy rain across the district earlier this week, the council was forced to discharge wastewater into the Purimu stormwater stream, which flows out to sea through the Ahuriri Estuary.
The city's wastewater network is operating as normal, however, meaning residents can use showers, washing machines, toilets and dishwashers as normal.
Landslips at six sites across Napier Hill caused damage to the sewer network, while 12 of the 49 sewer pump station were inundated by floodwater but were still able to function.
The council spokeswoman said five of the sewer pump stations have been running 24/7 since the event began due to high flows.
"We also know that significant flows of water entered the sewer network from gully traps in properties in the flood-affected areas, through manholes and at the pump station sites themselves," she said.
Of the 330 assessments undertaken, 17 properties were found to be "severely" damaged after the floods. Photo / Supplied
Napier mayor Kirsten Wise admitted water pumps did not operate for a short period of time due to a power cut.
"It was a very short period of time as generators were used straight away," she said.
The council said it is pleased with how quickly most of the water was drained after the deluge and that their systems "don't work without people".
The spokeswoman said the stormwater network is designed for a one in 10-year event.
"We have an overland flow design which works with our usual stormwater network, meaning we use roads and parks as flood areas when required which is designed for a one-in-50-year event," she said.
"We try to keep stormwater flowing underground for smaller events, however, larger ones mean we have to use the overland network."
The spokeswoman said the council is still in the "response phase" after the floods.
"It is too early to understand the full impact to services as we are still working through the event," she said.
"We will be discussing lessons learned at a later stage when we are in recovery."
