An alternative, more radical, redesign of New Street Station - including demolition of The Pallasades shopping centre - was shelved because more than a third of the nearly £500 million cost needs to be found from the private sector.
The initial funding plan for the long-anticipated rebuild of the 1960s station will require £300 million from central and local government funding streams, with £167 million needed from other sources.
The Birmingham Post understands the relatively large chunk of nongovernment investment is the reason why designs by architects John McAslan and Partners - with a huge, sweeping glass roof covering the entire station - have been scaled back.
Significantly, The Pallasades shopping centre - frequently highlighted as a key reason for the dinginess of the current New Street layout - will remain above much of the expanded concourse level.
A new atrium will allow natural light in, but in a more limited fashion than originally envisaged by the current architects and also previous designs by Will Alsop.
A source close to the project said last night: "Considering the amount of money the project needs from the private sector, completely removing the shopping centre isn't considered an option any more."
Birmingham City Council's cabinet will today be asked to approve the scaled-back-scheme, known as Gateway 1, as opposed to the more ambitious Gateway 2 proposal.
The officer's report states Gateway 1 maxim-ises "the opportunity to partner with the new owner of the Pallasades Shopping Centre [Warner Estates]".
A summary of the business case report states: "In both the Gateway schemes there will be significant works to the exterior of the building and the retail above. The Gateway 1 introduces an atrium to bring natural light down to the concourse level. In Gateway 2 the retail level is reconfigured and a new all-over roof structure incorporating the atrium is introduced."
The report goes on to say that both Gateway schemes comfortably exceed the Government's benefit-cost ratio threshold of two to one - required to trigger state investment in major capital schemes.
Meanwhile, a Centro report to be considered by the Passenger Transport Authority next Monday details the public sector funding arrangements for the station upgrade.
The Government is to be asked for £100 million through the Local Transport Plan bid system, £100 million will come from regional development agency Advantage West Midlands, both Birmingham City Council and the PTA will contribute £10 million, with the remaining £80 million coming from the rail industry. ..SUPL: