Kaytech has played an important role in providing its heaviest grade geotextile to protect the linings on newly constructed raw water dams at Eskom’s Kusile Power Station in Mpumalanga. Roshcon SOC Ltd, an Eskom-owned service company, contracted Aquatan Lining Systems to install its HDPE liner and a highly effective protection geotextile. It was decided that Kaytech’s bidim A10 would be the ideal product.

Since 1978 a range of non-woven, continuous filament, needlepunched geotextiles has been manufactured from 100% polyester by Kaytech and distributed throughout Africa and internationally. The mechanical process of needlepunching imparts several significant advantages to these high performance geotextiles. Providing excellent resistance to abrasion and piercing, while still retaining a high tensile strength, heavy-grade bidim A10, is the ideal cushioning protection for above or below liner systems. Ease and speed of installation compared to sand protection layers, especially on slopes, is another great advantage. The in-plane drainage characteristic dissipates pore water pressure build-up beneath the liner and the inclusion of bidim can extend the life and maintain the integrity of the lining system.

The Kusile raw water dams project commenced in March 2012 and had almost reached completion when contractors were requested to cease operations due to illegal strikes by construction workers. During this downtime, severe weather damaged a large area of HDPE liner and bidim A10, both of which had to be replaced.

Fortunately the ease of application of this geotextile facilitated the process of repairing the embankments where the stone particles of the in-situ soil were too large to obtain the correct working surface. Approximately 25 000m² of bidim A10 were used to reline the dam walls which were sloped at 1V:3H.

Aquatan Lining Systems, who had previous experience using Kaytech’s geotextiles, was highly impressed with the ease of application and time-saving benefits of such a top quality product, and proclaimed that bidim A10 was technically proven to be an effective liner protection for this application.

A 27km water pipeline running from the nearby Kendal Power Station is nearing completion. This 800mm diameter Nominal bore steel pipe will deliver raw water from the Vaal River Augmentation Water Scheme managed by the Department of Water Affairs, to the new dams. The pipeline crosses provincial roads, railway lines, petrochemical lines and the N12 national road on its journey to Kusile Power Station.

By completion of the project, Kaytech had supplied 100 000m² of bidim A10 as protection for the linings of the raw water dams. The bidim A10 quantities used in this project equate to 629,630 recycled PET cold drink bottles, which were used in the manufacture of bidim.

Generally, a coal-fired power station takes approximately eight years to construct and once completed, Kusile will be Eskom’s second most advanced coal-fired power plant after Medupi in Lephalale, Limpopo.