An independent inquiry will investigate what the NSW Premier has described as an "appalling" incident, in which a 15-year-old girl suffered an electric shock while walking near an "exposed wire" at the light rail construction in Sydney's CBD.

Anna Lambden had been at lunch with friends on Sunday when she took off her uncomfortable high heels and walked towards the train station in wet socks.

As she waited at the intersection of George Street and Ultimo Road near Haymarket, she felt a sudden shock which felt like pins and needles coursing through her.

"She felt it started at her legs and then it travelled upwards," her mother Viola Morris said.

"She was screaming out and then she dropped into the foetal position with her legs tucked up next to her."

The corner of Ultimo Road and George Street where Anna Lambden collapsed after feeling pins and needles sensation. ( Supplied: Google Maps )

Ms Morris said several passers-by tried to help but as they tried to touch her they also received shocks.

An ambulance was called and Anna was taken to Royal Prince Alfred Hospital when doctors told her that her injuries were "consistent with an industrial amount of electricity", Ms Morris said.

"She's really shaken by the whole thing because she thought that she was going to die yesterday."

Investigation underway

The NSW Transport Minister Andrew Constance said an inquiry had begun.

"There will be an independent investigation separate from all third parties that are involved in that area — wouldn't matter if it was RMS [Roads and Maritime Services], the light rail project itself, or alternatively some of the other third-parties … who might be involved in terms of management of electricity out of the pit in the footpath," Mr Constance said.

"Work has stopped on site at the moment until that initial investigation is undertaken and we can actually work out exactly who is responsible and what has occurred. At this stage that is not clear.

"But ultimately, we're very very sorry to that family and what has occurred here."

Mr Constance said the company responsible for the light rail project had been in contact with the teenager's family.

New South Wales Premier Gladys Berejiklian said she was devastated about what happened.

"I would have the same reaction as her mother did," she said.

"I think it's appalling that it occurred, and no pedestrian anywhere around a construction zone — no matter what project it is or what incident it is — should have to face that risk."



Ms Morris said doctors told her the fact that her daughter survived the initial shock indicated that there would be no lasting impact from the incident.

The teen's mother said Anna returned to hospital on Monday night because she had experienced problems with weight bearing and the pain was affecting her sleep. She briefly returned to hospital for treatment before being discharged.

"I'm devastated. The idea that a child can't walk the streets of Sydney without fear of electrocution is overwhelming to me," Ms Morris said.

"She's just 15 years old … she's a really nice kid and she was just innocently trying to walk to the train station and she just got struck — it's awful."

Ms Morris said she was worried a similar incident could happen again.

"I think the fact that this has occurred shows that there's been gross negligence on the part of the provider of the light rail service," she said.

"I don't feel assured that this will never happen again. I don't feel assured that they're going to do a proper investigation at this stage.

"The fact that there's been so little follow up and I've had to initiate it to get to this process is incredibly disappointing."