SPOIL FROM tunnels on London's eastwest Crossrail project could be used to build up the River Thames floodplain ahead of future development, project promoters said last week.
The decision comes as engineers try to find cheaper alternatives to landfilling construction waste.
Landfilling will be more expensive as tax increases over the next few years and capacity is reduced (NCE 17 June).
'We'd like to avoid paying landfill tax so we're looking at using excavated material to raise flood plains on development sites, ' said Crossrail head of operations and development Keith Berryman.
Berryman added that most of the spoil would be uncontaminated so it could be also used as capping material for landfills.
A Crossrail spokesman confirmed that a landfill site in Pitsea, East London, with rail links to Stratford, had been identified for this use.
The first phase of building Crossrail is expected to involve tunnelling 30m below ground between Paddington and Liverpool Street stations.
Berryman said that most of the 8M. m 3of tunnel spoil between Paddington and Stratford stations would be 'good, clean clay'.
But he added that developing details of where the clay would go had been stunted because of uncertainty on when the scheme would be delivered.
Promoters are still waiting for ministers to decide whether to go ahead with the project.
If it gets the go-ahead this summer, tunnelling should take place between October 2008 and August 2010.