Sydney Harbour drilled for rail link

Drilling has begun in Sydney Harbour to test a pathway for the NSW government's North West Rail Link.

NSW Transport Minister Andrew Constance launched his new post-election portfolio by promising to begin construction in 2017 and complete the project in 2024.

"This is going to, I think, revolutionise rail community across the city," he told reporters on Wednesday.

By drilling holes in the harbour, workers will determine the best route to continue the North West Rail Link from Chatswood into the CBD.