Megaprojects, such as the construction of airports, transport lines including railways and motorways, power plants and aerospace projects, typically cost more than $1bn.
Their scale, high levels of complexity and substantial impact on communities, the environment and state governments make them notoriously “difficult to manage” the researchers from University College London said.
The study, published in Project Management Journal, found that no isolated factor can account for the poor performance of megaprojects.
Instead, the paper claims to be the first to identify several causes and suggest a systemic approach to enhance understanding of megaprojects.
Over-optimism, poor governance and the risks of using new technology are among the issues found to cause large schemes to run over budget and behind schedule.
Conflict between various organisations and poor leadership were also highlighted as causes for so-called megaprojects not going to plan.
HS2 was given the go ahead earlier this week despite a decade of sharply rising costs and repeated delays to the original project timeframe.
Crossrail was also due to open in December 2018 and its budget was set at £15.9bn in 2007. But it is more than two years behind schedule and will cost an estimated £18.25bn.
The team assessed 6,000 academic summaries on the subject and whittled these down to full analysis of 86 papers.
Dozens of solutions were proposed by the researchers, including assessing what could be improved on previous schemes, removing ambiguity from the scope of work and focusing on simplification.
Professor Peter Hansford, a former chief construction adviser for the Government and an honorary professor at UCL, said: “The success of megaprojects is vital to economies across the world.
“But all too frequently they fail to satisfy their objectives in material respects – sometimes with very serious social and economic consequences.
“It is therefore of urgent importance to understand why megaprojects under-perform and what needs to be done to prevent them doing so.”
Mark Thurston, CEO of HS2, said: “We at HS2 were pleased to contribute to what is an impressive and exhaustive piece of research into the world of megaprojects, covering both the practical and academic arenas.
“But what is really crucial is it has concluded on some key themes that those of us who wrestle with these challenges every day can apply as a useful guide to help drive success, something that both the profession and wider society will benefit from.”
Source: eandt.theiet
