Abstract:
Many road projects in Tanzania experience extensive delays, thereby exceeding the planned
project duration date which often lead to cost overruns, time overrun, disputes and claims
between the parties involved. The main objective of this study was to assess the most
common causes of Variation Orders in construction projects at Arusha, its effects and suggest
possible measures to grapple with the persisting problem. This study answered three key
questions which were: what are the causes of Variation Orders in road construction projects in
Tanzania, what are the associated effects resulting from such situations, and what measures
can be taken to minimize the detrimental consequences caused. The main methodology
employed was a questionnaire survey conducted among 89 major road project stakeholders
who included owners, contractors and consultants. The Relative importance index of each
cause and the effect was carried out. This study identified the most common causes of
Variation Orders in road construction projects. Besides, exploratory factor analysis was carried
out to eliminate variables that are not purely factorial and grouped the core causes under four
principal cause groups, namely; competence of the consultant, external elements, competence and project management of the contractor and administration and financial
management of the owner. Finally, the probit regression model was applied to identify the
level of influence of each factor group on the completion time of road construction projects. In
the same vein the most consequential effects of Variation Orders identified in this study
include extended completion time of the project, cost overrun, disputes and claims, negative
social impact and arbitration. Overall the study has further shown an average time overrun of
40.4% higher than the original construction durations and cost overrun of 25.1% higher than
the original budget in road construction projects. The study ends with recommendations for
each of the parties in order to minimize and avoid the causes of Variation Orders and make
sure that projects are completed within the planned timefram
