The theory was initially considered by some of those involved early on in the case before sinister alternatives, such as abduction, were developed by cops
MADELEINE McCann could have fallen down a storm drain after leaving her Portugal apartment, new Netflix documentary The Disappearance of Madeleine McCann claims.
The theory was initially considered by some of those involved early on in the case before sinister alternatives, such as abduction, were developed by cops.
Cops in 2014 also opened manholes and began searching stormwater drains in 2014 in a bid to scour the region's underground sewerage system.
Maddie disappeared from her bed on May 3, 2007, while on holiday with her parents and family friends at a resort in Praia da Luz, Portugal.
Her parents, Gerry and Kate McCann, had left her sleeping with her siblings while they had dinner at the hotel's restaurant - only realising about 10pm that she was gone.
The notorious missing child case is the subject of a new eight-part documentary on Netflix titled The Disappearance of Madeleine McCann.
Barry Sadler, a local property developer, told the documentary producers: "When you leave the main road and the tourist areas, there are wells all over the place.
"I'm sure the child didn't wander up there them-self, but you don't know, accidents could happen."
And journalist Jon Clarke recalled the initial fears that perhaps Maddie fell into a construction workers' trench nearby.
"There was a big trench... leading all the way down the road about this wide and 6ft deep and there were two or three guys working in the trench.
"You kind of think, could she be down there, could she have fallen down there? Could they have buried her by accident?"
However, without the discovery of a body the theory was mostly ruled out by police, who instead turned to first falsely accuse Kate and Gerry of being involved, before later focusing on unknown abductors.
Investigator and author Anthony Summers told Netflix producers: "Perhaps the most telling sighting of all is that of Carole Tranmer who had been out to see her aunt who was living in the apartment immediately above the McCanns.
"Carole was looking out of the window.
"She said: 'Looking down below the McCann flat I saw someone come out of the ground floor apartment closing the gate very carefully and quietly.
'It looked very strange to me. He looked to one side and the other, shut the gate and walked very quickly below. This is on the afternoon of the day Madeleine is going to disappear.'
"What had struck her as peculiar, she said, was 'the way the man had closed the little gate down there. It his furtiveness that got my attention. The man had moved stealthily as if he didn't want anyone to know he was coming or going'."
Mr Summers added: "That has to be significant in any investigation of this case."
It comes as we reported how the President of the Portuguese Association of Missing Children, Patricia de Sousa Cipriano, told the Netflix producers: "We have information that our country is used by traffickers to pass children to other countries.
"They enter the country through the Algarve and then they go to Spain, to France, to Germany, to be exploited.
"They have a very strong structure that allows them to move human beings from one country to another in a matter of hours. It's frightening because it's very easy."
In 2011 Kate also wrote her own account of what happened that evening for a book titled "Madeleine: Our daughter's disappearance and the continuing search for her".
In it, Kate reveals Maddie's haunting words to her the day before her disappearance.
She wrote about how Maddie asked her: "Why didn't you come when Sean and I cried last night?"
Kate wrote: "Madeleine didn’t answer or elaborate. Gerry and I were disconcerted. Could Madeleine and Sean have woken up while we were at dinner? If so, it was worrying, obviously, but it didn’t seem very probable."
Meanwhile, Maddie's parents have slammed the new Netflix documentary on her disappearance, saying it "won’t help" the search.
The family also believe the controversial new film could "fuel conspiracy theorists", their spokesman said.
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