IMPACT ASSESSMENT OF RIVERINE TERRAIN INDICES ON COST AND TIME PERFORMANCE OF BUILDING PROJECTS IN ONDO STATE, NIGERIA

Abstract

Mankind is faced with the need to battle nature and produce a sustainable environment suitable for living for its residence. Construction risks, methods and liabilities varies with location, this is more so in riverine regions. Riverine project has so far been plagued with inadequate knowledge of these factors because the forces at work in the riverine is quite different from the other terrestrial regions, hence this study has been carried out to assess the impact of terrain factors on the cost and time performance of building projects in the riverine region of Ondo State. To achieve this aim, the study adopted a quasi-experimental research design due to its suitability for this kind of research. This allows for the assignment of samples into groups, having the non-riverine terrain features as a control for the study. The samples, being building projects were not randomly assigned as it would have, in an experimental design. The samples pre-exist in their habitat, and by virtue of location, belong to a group by default, and so cannot be randomly assigned. Four objectives were outlined to achieve the set goal. The data needed to achieve objectives was obtained through an interview of nineteen (19) professionals, analysis of fifty-three (53) project document and the use of the Geo-Information System (GIS) technology. The first objective to identify some of the different terrains indices that could affect the performance of building projects in the riverine, was achieved with the aid of using different tools and data as obtained through the use of questionnaires. it is discovered that several indices affect riverine construction cost and time generally and some are peculiar to the riverine alone. Some of the most important indices are; fees paid for community development, transportation, soil nature, terrain relief (or elevation), weather condition, building type, labour fees amongst others, and through the analysis of project document for obtaining data for the research, and regression analysis, the study ascertained the extent at which these riverine terrain conditions affect building project cost and time performance. The impact assessment was performed using multiple regression model. Findings reveal that riverine terrain indices such as soil nature, terrain nature, and relief has a significant impact on construction cost and time. The strength of the relationship between cost and time was tested using Pearson moment correlation and results show that cost – time relationship shows a strong positive correlation (R = 0.821), which is statistically acceptable. The study thus concludes that construction in the riverine is costlier as expected but it also shows the factors responsible for this. These are the factors to consider when engaging in riverine construction. This research has to a great deal bridge the gap in knowledge about the mysterious uncertainties as to the items that affect construction performance in the riverine. The study also recommends that similar research should be made on other terrains such as mountainous terrains and desert terrains.