Napier City Council is warning residents not to swim or fish around the Ahuriri area, after heavy rain over the past couple of days forced the discharge of stormwater mixed with some wastewater into the estuary.
NCC said in a release the discharge took place about 1am into the Purimu stormwater stream and warning signs have been put in place.
The council yesterday asked residents to be frugal in using wastewater by limiting showering, flushing of toilets and using sinks until the network can recover from the downpours.
About 90mm of rain fell at McLean Park in the 24 hours to midnight last night - almost double the usual average for the entire month of September (58mm).
NCC chief executive Wayne Jack thanked Napier residents for holding off on creating wastewater, and said this morning's discharge was done at the most opportune time when the majority of the flow would have been stormwater.
He said manhole covers were beginning to lift around the city, which could have caused a public health risk and the decision had to be made.
Mr Jack also said work is in the pipeline to identify properties where stormwater is incorrectly routing into the wastewater network, causing burdens at times like this.
This will include smoke detection, where smoke is pumped into the wastewater network, making it easy to identify where piping is incorrectly installed.
Testing of water quality around the Ahuriri area will continue in coming days.
Other Hawke's Bay residents have shared images from around the region showing the extent of the flooding.
MetService says the rain is likely to continue today and tomorrow in Hawke's Bay, before easing over the weekend, but also says gale-force winds are forecast to hit tomorrow in exposed areas.
For a full forecast for your area, see our weather section here.
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