Auckland Transport has selected two construction consortia to begin the first phase of construction of the City Rail Link.

The Connectus venture and Downer and Soletanche Bachy joint venture have won the construction contracts for the first Downtown phase.

City Rail Link spokeswoman Carol Greensmith says the construction industry has shown strong interest in the project.

She says the selection of contractors hasn't bee easy and the tender process has been thorough and rigorous.

"We spoke to all the key players in the construction industry, they all had to tender for the work, and all those tenders were evaluated by a team of experts. It's just sort of that first step to get going, so the construction industry knows we're coming."

Carol Greensmith says it's an important step towards building up the city's transport capacity.

"With all the motorways and key arterial routes in Auckland were cul-de-sacs we'd think it was stupid, but we have a rail system like that. Rail patronage is growing by over 20-percent a year at the moment and Britomart is a dead-end."

The contractors

The ink is fresh on the contracts but the final completion date for the project will depend on Auckland Council and Government funding.

Downer New Zealand will lead work from Britomart Transport Station to Downtown Shopping Centre from early 2016.

New business general manager Chris Moloney says the company is relishing its role.

“We are excited to have won a contract for the most significant improvement to Auckland’s transport network since the opening of the Auckland Harbour Bridge"

The Connectus Consortium will construct cut-and-cover tunnels along Albert St from Customs St to Wyndham St.

That work is expected to start in October with a major stormwater line in Albert Street between Swanson and Wellesley Streets being relocated.

McConnell Dowell managing director Roger McRae says the Connectus members McConnell Dowell and Hawkins have a long history of infrastructure construction.

"It's enormously satisfying to be working together on a transport project that is helping to shape the future."

The arguments

Larry Williams: At some point that City Rail Loop will have to be completed. A rail system ending in the city with just a few tracks is quite absurd. What Brown needs to do, and indeed the other councillors who are ideologically opposed to flogging off some assets to help pay for some of this, is think about what you want.

Josh White: It allows trains to flow through the CBD, so more trains can operate across the entire network. Yes, even trains that don't even touch the CBD. More cars off the road means an easier commute for those who drive to work.

Councillors: George Wood says there's also no guarantee that if the council starts the CRL early, that the government will come on board to fund work already completed. He also believes that the 50 percent promised by central government is not enough ... and he's worried there's no strongly constructed agreement in place over the funding.