 These cause a major buildup of traffic and are the main sources of pollution in the towns, notably in Strasbourg where the motorway traffic of the A35 was 170,000 per day in 2002.At present, plans are being considered for building a new dual carriageway west of Strasbourg, which would reduce the buildup of traffic in that area by picking up north and southbound vehicles and getting rid of the buildup outside Strasbourg.The line plans to link up the interchange of Hœrdt to the north of Strasbourg, with Innenheim in the southwest.