The multibillion-rand Bus Rapid Transit (BRT) systems which are being rolled out across South African cities need vastly increased densities to be successful and financially sustainable.

Three Gauteng metros have spent in excess of R10-billion on BRT projects, however, the system is averaging less than 60000 commuters in Johannesburg and Pretoria where the system is already operational. Transport experts have warned that with South Africa's lower densities and longer distances between where people live and work, the system will continue to struggle for years to draw bigger numbers of commuters and become self-sufficient.

Associate professor at the University of Pretoria's Centre for Transport Development, Christo Venter, said the BRT systems which have proven successful in South America faced different realities here.

Venter said the BRT systems "were not quite appropriate for our conditions. With our lower densities and long distances, BRT systems are much more expensive to build and run while people are generally not willing to pay much more for the higher quality we are trying to provide."

He said there's an urgent need to link BRT investments better with new housing and commercial developments built around them.

Venter said BRT made "absolutely no sense on its own", unless it was part of a whole integrated, restructured and improved network. Ekurhuleni, Joburg and Tshwane are currently spending in excess of R3-billion on BRT in the current financial year.