Shrouded in political undertones, the construction of the dam was vital for the hydro-electric power it would provide for Zambia's burgeoning copper industry. Little thought, however, appears to have been given to the future of the human and animal populations who lived in the valley that would be inundated when the dam was completed.

The question has to be asked: Was this awe-inspiring man-made creation achieved at too high a cost in terms of the human suffering and environmental devastation it caused?

Central to the story of Kariba was the fate of the Tonga people who had for centuries lived in the Gwembe Valley, due to be flooded when the sluice gates were finally closed to halt the flow of the Zambezi River. Approximately 57 000 people were forced to move from their ancestral homes, abandoning family graves and spiritual sites to the depths of Kariba's waters. They become a dispersed people who have never been able to reunite as a cohesive society, never again been able to live peacefully on the banks of the river which gave them life. Animals, too, perished in their thousands despite the gallant efforts of wildlife personnel who mounted a hastily planned rescue mission known as Operation Noah.

Whispers from the Depths gives a voice to the all but forgotten BaTonga. It celebrates their unique culture but deplores the price they paid for progress - a price from which they themselves derived no benefit whatsoever.

Written by Liz Wickins and Mike Wickins, Whispers from the Depths is published by Tracey McDonald Publishers.