By 1993 the motorway that was designed for a maximum of 88,000 vehicles per day was carrying 200,000 , 15 % of UK motorway traffic volume was on the M25 and there were plans to add 6 lanes to the section from Junction 12 to 15 as well widening the rest of the motorway to 4 lanes In parts , particularly the western third this plans went ahead , given consistent congestion however again plans to widen further sections to eight lanes ( four each way ) were scaled back in 2009 in response to rising costs , which are reinstated in the agreed Highways Agency 2013-14 business plan .
15 % of UK motorway traffic volume was on the M25 and there were plans to add 6 lanes to the section from Junction 12 to 15 as well widening the rest of the motorway to 4 lanes .