Putting context to numbers : a geotechnical risk trajectory to cost overrun extremism

Amadi, AI; Higham, AP

Abstract

The study investigates the cause of the unusually high cost overruns experienced
in highway project delivery in the tropical wetland setting of the Niger Delta
region of Nigeria. This is in view of the extensive literature supporting the link
between geology, the lack of geotechnical best practices and cost overruns. An
empirical profiling of cost overrun research further reveals the predominance of
mono-method studies based on survey methods, correlative analysis and archival
data modelling techniques, all of which are underlain by positivism. The study
argues that such positivist philosophies, although methodologically valid, cannot
adequately explain and provide in-depth understanding of the contextual cost
overrun drivers in highway organisations., Using a robust and thoughtfully
designed mix of methods, the paper examines the contribution of geotechnical
risks to cost overruns experienced in highway project, and demonstrates the
relevance of context in cost overrun research. Cost overrun data from
documentary sources for 61 completed highway projects in the Niger Delta are
gathered and analysed, revealing an average value of 216%, with extreme cases,
ranging up to 1925% of budgeted cost. To uncover the intrinsic contextual
drivers, 16 interviews were conducted with participants from the three highway
agencies in the region, responsible for the execution of the sampled highway
projects. Adopting a geotechnical narrative, the data is thematically analysed,
deductively and inductively. The results of the analysis identified that poor
project governance, management and procurement practices, have inhibited the
competent management of geotechnical risk, creating a propensity for extreme
cost overruns on the highway projects. The study submits the phenomenon of
cost overruns in public infrastructure projects is underlain by a complexity of
contextual social constructs, which would have been overlooked in positivists
studies. Cost overrun research therefore, needs to be contextually and
numerically anchored.

Keywords: Context, Cost overruns, Highway projects, Mixed methods, Social
Constructs

Citation

Amadi, A., & Higham, A. (2019). Putting context to numbers : a geotechnical risk trajectory to cost overrun extremism. Construction Management and Economics, 37(4), 217-237. https://doi.org/10.1080/01446193.2018.1513656

• Journal Article Type: Article
• Acceptance Date: Aug 14, 2018
• Online Publication Date: Nov 19, 2018
• Publication Date: Jan 1, 2019
• Deposit Date: Oct 12, 2018
• Publicly Available Date: Nov 19, 2019
• Journal: Construction, Management and Economics
• Print ISSN: 0144-6193
• Electronic ISSN: 1466-433X
• Publisher: Routledge
• Volume: 37
• Issue: 4
• Pages: 217-237
• DOI: https://doi.org/10.1080/01446193.2018.1513656
• Publisher URL: https://doi.org/10.1080/01446193.2018.1513656
• Related Public URLs: https://www.tandfonline.com/toc/rcme20/36/9?nav=tocList