Raw sewage flooded cells and common areas at Auckland's Paremoremo prison today, leaving a foul smell for inmates and officers.
The cause had been put down to a system blockage which resulted in sewage flooding areas of the prison's A block including the recreation room, education areas, an office and 24 out of the more than 600 cells.
Auckland Prison director Tom Sherlock said contractors had been on site working to resolve the issue.
He said the blockage resulted in sewage flooding "isolated" areas.
"We do the upmost to ensure the health and safety of staff and prisoners and have established processes to ensure that any potential health risks of such an event are managed. Personal protective equipment has been provided to those involved in cleaning up, and all internal areas affected have been decontaminated."
This is the second time this week parts of the prison's A block have been flooded with waste.
On Monday morning a source revealed several rooms in the prison, including the computer room and the indoor recreation area, had been covered in sewage that had spilled from the toilets overnight.
The man, whom the Herald has chosen not to name, said prison officers did not become aware of the incident until 7.30am on Monday.
"This is the third time this has happened. Most institutions have audible sewage overflow alarms, but as we know, Corrections don't mind placing inmates health at risk."
Mr Sherlock confirmed the spillage on Sunday night and said the area had been cleaned.
"There was a system blockage this morning which resulted in sewage overflow affecting the recreation room, education area and PCO office in A Block. Facilities management contractor, Spotless, was called to assist.
"The clean-up took approximately two hours once the professional team arrived and the affected areas were reopened and cleared for use."
He said sewage spillage was not a common occurrence and the prison was reviewing both incidents to identify the cause and prevent future occurrences.
In May last year the prison was forced to apologise to its neighbours in Paremoremo for an overflowing sewer that has caused a stench sporadically for years.
The sewer, owned and operated by the Corrections Department, had caused a stink in nearby Te Araroa Drive several times and overflowed several times.
A resident said that at its worst the stench from the sewer was so bad that his family found it impossible to walk in their garden.