Article révisé par les pairs
Résumé : The construction of a large metropolitan infrastructure, like other megaprojects, requires advanced technical expertise, capacity to manage complex procedures and planning processes as well as capacity to deal with conflicting interests. For the case of megaprojects, overestimation of benefits and underestimation of costs and risks is a common problem all over the world, leading to the 'survival of the unfittest’ (Flyvbjerg, 2009). The main causes were identified in the optimism bias, strategic misrepresentation, path dependency leading to lock-in and poor oversight; however, the 'survival’ of these causes is still unclear. For this purpose, the survival of the unfittest megaprojects is re-conceptualised into a proper cognitive-evolutionary framework. By introducing an innovative taxonomy of policy knowledge, this paper aims to argue that a specific policy community can 'survive’ by strategically using a ‘cognitive monopoly’ of some of the relevant policy knowledge for megaprojects. Based on the case of the new ‘Watermael – Schuman – Josaphat’ rail junction in Brussels, findings show the critical role played by the Federal Ministry for Communications thanks to a long-standing and context-specific know-how on underground works. While missing knowledge was outsourced and instrumentally used to overcome potential lock-in, the Ministry was able to build the only new large metropolitan infrastructure of Belgium during a period of high uncertainty due to decentralisation. The paper concludes discussing the effects of preserving this policy knowledge as well as negative issues related to this ‘cognitive monopoly’.