Members of the Building Collapse Prevention Guild (BCPG) Iru-Victoria Island Cell have called for mandatory subsoil investigations, especially in coastal areas, to curb incidents of building collapse.
The group expressed concern over inadequate subsoil investigations in the coastal region of Lagos State, which they said often lead to structural failures.
Noting that Iru–Victoria Island Local Council Development Area (LCDA) is surrounded by the Five Cowrie Creek and the Atlantic Ocean, the BCPG said conducting comprehensive subsoil investigations to determine the mechanical properties and shear strength of the soil that can bear the load exerted by a building’s foundation is essential.
It stressed that soil testing is a crucial step in building development, particularly in coastal regions, to prevent collapses caused by foundation failure. According to the group, a properly conducted geotechnical subsoil investigation report enables civil and structural engineers to determine and design the most suitable foundation type for a proposed building.
In a statement jointly issued by its Coordinator, Adefemi Afolabi, an architect; General Secretary, Taiwo Ayanboade, a quantity surveyor; and Public Relations Officer, Wale Oyetayo, a civil/geotechnical engineer, the group stated that the lack of effective regulatory monitoring of geotechnical practice in Lagos State could lead to more building collapses in Iru–Victoria Island LCDA.
It noted that investigations revealed a mismatch between execution costs and contract sums, which often results in substandard soil tests. According to them, “this excuse by some practitioners is not tenable since no one compelled them to accept low prices.”
The BCPG Iru–Victoria Island Cell reiterated that ensuring the integrity of subsoil investigations is critical to safeguarding lives, property, and investments in the coastal region of Lagos State. While it acknowledged efforts made to strengthen building control processes, it said more still needs to be done in geotechnical practice.
The group also called for collaboration between government agencies, professional bodies, and industry stakeholders to build capacity, enforce standards, and foster transparency in soil testing operations. It stressed the need to evaluate laboratories conducting shear strength tests such as Oedometer Consolidation, Atterberg Limit, and Triaxial Compression tests on in-situ soil samples.
To enhance credibility, it said, the building plan approval system should include procedures to verify soil test reports and minimise the risk of copied or falsified submissions.
The BCPG noted that the establishment of the Lagos State Materials Testing Laboratory (LSMTL) by law in 2006 was intended to curb poor geotechnical practices. Unfortunately, it said, “the agency that was supposed to play the role of disciplinarian umpire entered into the business of soil testing, thereby competing with the firms it was established to regulate.”
It argued that the agency’s revenue generation drive is counterproductive as it compromises standards, and called on LSMTL to stop playing the dual role of regulator and revenue-generating soil testing agency.
“LSMTL should now wield the big stick to sanitise the geotechnical sector. Any firm that wants to practise geotechnical investigations in the state must undergo scrutiny for possessing appropriate plants, equipment, accessories, experienced drillers, and analytically competent supervisors.
“A training school for drillers should be established by the Lagos State government in conjunction with the Nigerian Institution of Geotechnical Engineers, the Nigerian Association for Engineering Geology and the Environment, and other relevant bodies.
“For a result-oriented approach, field work monitoring with enforcement teams is inevitable in the aspirations for satisfactory subsoil investigations.
“By addressing the identified challenges and prioritising professionalism above expediency, Lagos State can significantly reduce the risks of building collapse and set a sustainable example for other coastal cities in Nigeria and beyond,” it noted.
The group added that observations from geotechnical sites in Iru–Victoria Island and other parts of Lagos State have raised doubts about the primary objective of subsoil investigations as a prerequisite for building development.
“Many of the soil tests conducted were below standard. Section 4, Sub-section 3 (V) of the revised Lagos State Physical Planning Permit Authority Regulations, 2019 specifies that ‘subsoil investigation report [is required] in the case of structures in excess of two floors and all developments in areas with low bearing capacity soil.’
“This regulation has created exponential demand for subsoil investigations, thereby exposing the unpreparedness and limitations of geotechnical firms. Although the challenges are being endured silently by practitioners in order to protect the business from low patronage, the need to avert the future disastrous consequence of downplaying the challenges necessitates bringing into the open constraints in the geotechnical field.”