<Li> The cost of £ 537 million compared to cost of 1908 Olympic Stadium £ 60,000 (£ 5.6 million in 2010). </Li> <P> The stadium site is on former industrial land between the River Lea (which rejoins the Navigation below Old Ford Lock), the City Mill River, and the Old Pudding Mill River; parts of the Bow Back Rivers . Another branch of this system, St Thomas' Creek, 200 metres (660 feet) to the south, completes an "island" surrounded by water . 200 metres (660 feet) to the east is the Waterworks River; with the London Aquatics Centre on its eastern bank . This "island" site for the stadium lies at the southern end of the Olympic Park . To make room for the stadium, the already partially obstructed Pudding Mill River, a short channel of the Lea which ran from the west side of the stadium south - eastwards across the stadium site, was filled in . </P> <P> Dennis Hone, chief executive of the LLDC, revealed in November 2012 that the stadium would not meet its reopening deadline of 2014 . Instead the stadium would reopen in August 2015 with the stadium retaining a capacity of around 50,000 for athletics . Following the granting, in March 2013, of a 99 - year tenancy to West Ham United, the E20 LLP, a joint organisation by the London Legacy Development Corporation and Newham Council were specifically set - up to oversee redevelopment of the stadium into a UEFA Category 4 venue seating 60,000 spectators . The reconfiguration saw work on a new roof, corporate areas, toilets, concessions and retractable seating . West Ham contributed £ 15 million and Newham Council £ 40 million for the work to be carried out with the LLDC and the British Government making up the rest . Approval was granted for the installation of retractable seating on all sides of the stadium and an 84 - metre (92 yd) transparent roof . </P> <P> Balfour Beatty were initially contracted to construct the new roof for £ 41 million; in January 2014 they were awarded a £ 154 million tender, which includes the earlier contract for the roof, to complete the stadium's transformation works . Imtech G&H were awarded a £ 25 million contract to carry out electrical and plumbing work . Paul Kelso, working for Sky News, discovered in September 2014 that the cost of the conversion of the stadium may rise by £ 15 million, due to additional work to strengthen the structure, to allow it to support the new roof . It was revealed neither West Ham United nor the taxpayer would have to meet the additional cost as Balfour Beatty would contribute with the remainder funded from the existing LLDC transformation budget of the Olympic Park . In October 2014, the LLDC contributed a further £ 35.9 million towards the project with the funding coming from reserves and income generated by other means . </P>

What changes were made to the london olympic stadium
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