Civil Defence has reassured concerned Gisborne residents that no sewage was discharged from a local pump station during this week's flooding.
Monday's heavy rain left more than 50 properties in the Graham Road area covered in silt, and locals were concerned about the lack of information they were getting about possible sewage contamination.
But Civil Defence said the closest discharge of sewage to Graham Road happened downstream on both sides of the Gladstone Road Bridge.
However, it did warn that livestock contamination from farm run-off in the wider catchment remained a hygiene risk.
Gisborne Civil Defence emergency manager Louise Bennett said it was safe for residents to clean up their properties as long as they followed normal hygiene procedures,
"People should wash their hands with soap and water after handling anything contaminated with floodwaters, before eating or preparing food, after taking part in any flood clean-up activities," she said.
Civil Defence said residents in the Graham Road area were incorrectly told by Fulton Hogan contractors on Monday that the council was going to discharge sewage at the Graham Road pump station.
Stormwater was discharged, however, with diluted wastewater released into the Taruheru, Waimata and Turanganui rivers from the city's sewerage network.
The valves were opened late Sunday night in order to avoid sewage flowing back onto private property with the last valve closed last night.
Mrs Bennett said most of the 40 properties affected by Monday's flooding have flooded in the past and will flood again in the future.
"I expect that the affected properties are identified in their Land Information Reports as flood-prone areas. We advise residents to follow basic hygiene procedures when cleaning up their properties.
"Also, it's advisable to keep pets outside while covered in silt.
Almost a metre of water flooded the bottom storey of Anna-Maria Hunt's Graham Road property, destroying her lounge suite, a bed, table and carpets.
The water has now gone, leaving ankle-deep silt. Mrs Hunt said when the council arrived, they told her it was not their problem, but the insurance [company] or owner's problem.
Mrs Hunt said their response was appalling, considering she did not know whether the silt was contaminated by sewage and whether it was even safe to clean up.
She said her insurance company gave her the all-clear to clean outside, but the council's message had been harder to understand. "They said it's not [safe to clean], you shouldn't do anything. And then the insurance people said just carry on, you can start outside, but not inside."
Across the road, Matt Smith has been busy mopping up the mess the flooding caused in his two-storey home.
"We had a whole team of guys with water blasters, brushes and brooms... to get it cleaned up," he said.
"It's not actually looking too bad downstairs but the carpets are stinking of sewage and mud."
Mr Smith's neighbour, Mark Kingsbeer, had been helping out residents. He said Civil Defence, run by the council, said there could be contamination from the wastewater station at the end of Graham Road.
"A call was made to say that there is a possibility of sewage being in the water and we were to stop immediately and make sure that we showered. Any cuts that we had were to be treated with antiseptic cream and that [we] weren't allowed to help any further other than that."
Mr Kingsbeer said he also got a voicemail from the council saying there might be sewage in the silt.
Bridge build-up blamed for flood's impact
Some Gisborne residents said if the Gladstone Road Bridge had been cleared of debris earlier, the impact of flooding in the area would have been less serious.
Mr Smith said all residents knew debris from forestry harvesting piling up against the bridge in bad weather was an ongoing issue.
He said flooding problems could have been avoided if the council had regularly cleared the bridge of debris build-up, and a crew should be on call to keep the bridge clear.