The recent emergence of sinkholes and fissures especially in Nakuru County has brought into sharp focus the need to consult geologists before embarking on construction projects.
The phenomenon has occurred following torrential rains that have pounded large swathes of Kenya. But it is Nakuru County that has borne the brunt of the incidents. In certain areas, buildings have been destroyed while others sit right on the path of fissures and risk suffering similar fate.
According to the Ministry of Mining, ground subsidence, which is the technical term for sinkholes, poses extreme and grave dangers to lives, property, livestock and infrastructure. “Geologically and tectonically, Nakuru County is located in an area prone to various geohazard types including sinkholes, landslides and earthquakes”, states the Ministry. “The western part with its complex network of underground drainage channels draining through porous unconsolidated pumice and volcanic ash is most prone to such hazards. These drainage channels create significant susceptibilities on the structural integrity of the land by forming subterranean tunnels and cavities which ultimately result to creation of sinkholes that damage property and roads.”
The Ministry says that Nakuru has a history of this phenomenon, with incidents reported since 1972. It calls for immediate intervention to avoid accumulation of excess water on the surface and the construction of adequate storm drains and waterways within the town and residential areas to allow free and fast flowing of water to destination water bodies.
“Additionally, in-depth geophysical survey is needed determine the depth of damage, area geology, rock profile and depth to the basement rock.”
Developers and other builders ought to take great caution before commencing projects in areas that are prone to these incidents. Consulting a geologist is therefore just as important as consulting other professionals. However, it is important to note that engineers are also competent to assess ground conditions at a proposed site.
How Geologists Can Help
- Site Suitability: A geologist can assess whether the site is suitable for the planned construction. They can identify any geological hazards, such as landslides, sinkholes, or seismic risks, which could affect the safety and stability of the building.
- Foundation Design: Geologists can provide valuable information for designing the foundation of the building. They can assess the soil and rock conditions to determine the best foundation type and design to ensure the building’s stability over time.
- Water Management: Geologists can evaluate the site’s hydrogeology, including groundwater levels and flow patterns. This information is crucial for designing effective drainage systems to prevent water-related issues like flooding or foundation instability.
- Material Selection: Geologists can also provide insights into the availability and suitability of construction materials, such as rocks and aggregates, which can impact the project’s cost and sustainability.
- Environmental Impact: Geologists can assess the potential environmental impact of the construction project, including the risk of soil erosion, habitat disturbance, or contamination.
Overall, a geologist’s assessment can help mitigate risks, optimize construction plans, and ensure the long-term stability and sustainability of the building project.
