HS2 tunnel 'could protect Chilterns'
High-speed trains would travel at speeds of up to 250mph between London and Birmingham
A £1.85bn 15-mile (24.7km) tunnel could protect an area of outstanding natural beauty in Buckinghamshire from damage caused by the HS2 high-speed rail line, says a report.
The study commissioned by Chiltern District Council looks at how to avoid damage to the Chilterns.
It says a tunnel "avoids the loss of ancient woodland and impact on listed buildings and scheduled monuments".
The cost represents 2% of the overall cost of HS2 phase one, says the report.
The study was produced by development consultancy Peter Brett Associates and commissioned by Chiltern council in association with Aylesbury Vale District Council, Buckinghamshire County Council and the Chilterns Conservation Board.
The preferred tunnel route would go under the River Misbourne at Chalfont St Giles as far as the A404 and then follow the A413.
Leader of Chiltern District Council Nick Rose: "HS2 would create a huge and ugly scar.
"Our proposal represents a huge improvement over the existing government proposed scheme and avoids the reckless damage that the rail line would cause."
Steve Rodrick, chief officer at the Chilterns Conservation Board said: "The Chilterns area of outstanding natural beauty is natural heritage and we expect those responsible for designing the HS2 railway to protect this special place.
"A long bored tunnel is the only acceptable solution."
A Department for Transport (DfT) spokeswoman said: "We are committed to protecting the environment, as per the mitigation measures set out in the Environmental Statement.
"The suggestion of a tunnel through the entire Chilterns area of outstanding natural beauty has been explored and given extensive consideration."
The DfT is proposing a much shorter 13.5km (8.4 mile) tunnel just inside the M25, to pass underneath a section of the Chiltern Hills.
The 100-mile rail link, which would be built between 2016 and 2026, aims to cut the London-to-Birmingham journey time to 49 minutes.
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