THE Ghana Institution of Geoscientists (GhIG) says the design and construction of the Aburi-Ayi Mensah dual carriage road was deficient in the application of geodynamics to the rock formation in the area leading to persistent falling of huge rocks after any heavy downpour.
The institution indicated that the toe of the hills (with rocks steeply dipping towards section of the road) was in direct contact with the road without any safety buffer.
Briefing the parliamentary press corps, Mr Crisler Akwei Ankrah, General Secretary of GhIG, said the road should not have been constructed facing the dip direction of the rocks, but rather on the other side of the hill.
“Besides, these high walls which are in close proximity to the road were not benched, so that the beams created due to the multiple bending would act as safety bays for any rock fall,” he said.
Mr Ankrah said another issue which might have aggravated the situation was the uncontrolled construction of buildings and access roads on top of the heavily fractured hill which led to slope failures facilitating the movement of rocks down the slope.
He also said clearing the vegetation for farming along the slope was another contributory factor which exposed the rock surface to water seepage into the fractures together with surface run-off leading to rock fall, slope failures and potential landslide.
Mr Ankrah said authorities must also ensure that mining of dimension stones for building purposes along the range which could also lead to disturbances in the structure of the rock’s unit, affects the slope stability leading to the rock falls, adding that illegal quarry activities was also weakening the stability of the rocks.
He asked the Ministry of Roads and Highways to as a matter of urgency create safety buffer zones from the road to the toe of the hill, and thereafter stabilise any steep slope along the stretch through multiple benching.
“Where necessary, various rock support techniques should be incorporated, such as rock or cable bolting, retaining walls geosynthesies and appropriate wire meshing,” he said.
Mr Ankrah said as a way forward to avoid such challenges anywhere along the range, there was the need to submit all materials for road construction buildings and other civil works to the GhIG for certification to determine their suitability of not containing any injurious minerals.
He said the GhIG was also ready to partner any government agency in standardisation of geomaterials suitable for road, buildings and any construction works, so that all stakeholders would have value for money and safety environmental stewardship that would ultimately lead to sustainable development
BY LAWRENCE MARKWEI