Engineering and construction company Costain has won a 150m pound deal to build a branch of London's Crossrail project.Costain said Network Rail (NR) had handed it the Crossrail North East Spur contract to build infrastructure and stations between Stratford in east London and Shenfield in Essex.Costain and NR will now start work on design work to develop detailed plans for the scheme, which includes big station upgrades at Romford and Ilford and station improvements at Forest Gate, Goodmayes, Harold Wood, Gidea Park, Chadwell Heath and Brentwood.Main works will start later this year and complete in 2017. Major infrastructure improvements will also include upgrading tracks and overhead electrification equipment.Chief Executive Andrew Wyllie said: "We are delighted Network Rail has awarded us this contract on Crossrail, currently Europe's largest infrastructure programme."PW