Welcome to the Costain Group.. Costain, in joint venture with Skanska, announces that it has been awarded a second contract by Crossrail, as part of its enabling works framework, for the construction of the Pudding Mill Lane Portal The Costain team working on the AMP4 Welsh Water Framework have won a prestigious national accolade for the considerate way that it completed a £1million investment scheme in Colwyn Bay A West Wales road improvement project is bringing not only relief to frustrated drivers and beleaguered villagers but also plaudits to the Costain team building it