(AUS)Major engineering hurdles remain for new rail tunnel beneath city

[Pakenhamtrain]

From The Age:

 

 

Major engineering hurdles remain for new rail tunnel beneath city

February 28, 2013

 

SILTY soil, the cancer centre currently being built, the City Loop's
four tunnels and aquifers beneath the murky bottom of the Yarra River
are all major hurdles to building a proposed new rail tunnel beneath the
city.

 

Investigative work is well under way on building the proposed
Melbourne Metro tunnel, before the required federal funding to help pay
for the major project has been secured.

But project planners have yet to solve a number of
engineering challenges, the greatest of which is how to tunnel beneath
the Yarra River, which is risky due to the presence of aquifers and
softer ground.

Cracks have previously appeared in CityLink's Burnley tunnel
near the river, leaking water and costing hundreds of thousands of
dollars to repair.

 

 

http://www.theage.com.au/victoria/major-engineering-hurdles-remain-for-new-rail-tunnel-beneath-city-20130227-2f6dd.html#ixzz2MRiQTzZ7

 

Building the tunnel between street level would be interesting. Not much space. It goes:
LATROBE ST

Station masters office and concourse
LOWER GROUND FLOOR Melbourne Central Shopping Centre inc. Station Concourse.

Platform 1 and Platform 2.

 

I wouldn't think the space between the platforms and the concourse was than much. It would have to slot between the escalators.