Police in West Auckland say it would not have been possible for a child to shift the manhole cover on a drain where the body of Aisling Symes was found.
She was found on Monday night after police decided to dig up the drain near the Henderon house she went missing from.
Inspector Gary Davey said on Tuesday that police found the manhole cover was about 8 - 10cm ajar when they first checked the drain.
A police officer moved the cover out of the way and went inside the drain to check it.
Inspector Davey said the officer called Aisling's name and then climbed out, replacing the cover. He said cameras put into the drain also did not find her.
He said Aisling's father Alan Symes also checked the drain and did not find her.
Aisling, aged two years, went missing on Monday afternoon last week.
Inspector Davey said the police still don't know how the child died and a post mortem will be carried out on Tuesday.
While it seems likely that her death was an accident, he said police have not ruled out foul play or any other possibilities.
An Asian woman who was reportedly seen speaking to Aisling at the time she disappeared, has now been identified and
Inspector Davey said police are trying to locate her.
The area is being treated as a crime scene and has been cordoned off.
Waitakere City Council services acting director Tony Miguel told Nine to Noon it would be impossible for a toddler to move the manhole cover.
Family heartbroken - pastor
The pastor at the church that the Symes family attended says her parents are heartbroken by the discovery.
Pastor Russell Watts from Ranui Baptist Church told Morning Report that Aisling's parents had still held hope she would be found alive.