"It happened on Saturday, August 6, during the large storm that hit Hawke's Bay when we had no power."
He believed the generator must not have kicked in causing the sewage to flow out over the lid on to the grass.
He said there were a lot of feathers amongst the toilet paper and general waste, which he thought was very "odd".
"You do not usually expect to find that in a sewer and I expressed my concern to the council."
A Hastings District council spokeswoman said council staff had been unaware of the problem and apologised for taking so long to respond.
"Council had completed a first look at why the message from a member of the public asking that it be cleaned up did not reach the correct channels. The cause is not immediately obvious and council will look further into this."
Mr McDonald said he knew councillors had been and seen the waste but was shocked that nothing was actually done for at least two weeks.
Councillor Adrienne Pierce had looked at the mess and agreed that it was "disgusting". She was equally confused as to where the feathers may have come from.
The council denied there was any link to the gastro-outbreak, saying it was a very different matter.