Geoscientists recommend safety bays for falling rocks

Accra – The Ghana Institution of Geoscientists (GhIG) has recommended, as a matter of urgency, the creation of safety buffer zones for roads in mountainous and hilly regions from the roads to the toes of the hills.

Furthermore, steep slope along road stretches should be stabilised.

Where necessary, various rock support techniques should be incorporated, such as rock or cable bolting, retaining walls, geosynthetics and appropriate wire meshing, the institution advised, in a press release in Accra.

The release, signed jointly by Mr Chrisler Akwei Ankrah, the General Secretary; and Dr Yvonne Sena Loh, the Public Affairs Officer of the GhIG, is in reaction to the recent occurrences of rockfalls, slope failures and landslides and their consequential dangers to life and property.

Heavy rains have triggered landslides and rockfalls on the Akwapim�Togo Range, with the most recent one on the Aburi-Ayi Mensah stretch, creating inconvenience to pedestrians and motorists with near life threatening misses.

There are similar areas across the country where there is looming danger. These areas include the Kasoa Tollbooth, Ablekuma, MacCarthy Hill, Gbawe Kwabenya, Ofankor, the Nkawkaw Scarp, the Voltaian Scarp, Jamasi Asante Mampong Area, Gamabaga Nankapnduri Road, Larteh Road and their surrounding areas, which are subject to the risk of possible rockfalls and landslides.

The occurrence of these natural catastrophic events may be accelerated by heavy rains, earth tremors and earthquakes as well as the surge in uncontrolled, non-standardised and indiscriminate human activities, the geoscientists cautioned.

The earth scientists faulted the process by which the Aburi-Ayi Mensah dual carriage road was constructed, saying that during the construction of the dual carriage way, the footwall of the hill was cut back without adequate assessment of the geological structures and the general geodynamics of the hill.

Furthermore, the design and construction of the Aburi-Ayi Mensah dual carriage was deficient in the application of geodynamics to the rock formations in the area. The toe of the hill is in direct contact with the road without any safety buffer, the release said.

It added that the road should 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 berms created due to the multiple benching would act as safety bays for any rock fall.

The release said uncontrolled construction of buildings and access roads of the heavily fractured hill aggravated the problem that led to slope failure, facilitating the movements of rocks down slope; adding that clearing of the vegetation for farming along the slope exposed the rocks for water to seep into them, with possible rockfall, slope failures and potential lanslides.

The geoscientists recommended materials for road construction, buildings and other civil works to be certified by qualified geoscientists to ensure that the materials did not contain any injurious materials not suitable for building or civil works.

The GhiG stands in readiness to partner any governmental agency in the standardisation of geomaterials suitable for road, buildings any construction works so that all stakeholders will have value for money, safety, environmental stewardess that would ultimately lead to sustainable development, the release said.

Source: Ghana News Agency