Restoring power to the Kempton Park CBD could take a week, the Ekuhruleni municipality said on Thursday.

"We have a minimum period of five days for repairs and a maximum of up to ten days [from the date of the incdent]. We are trying to do the minimum," said Ekuhruleni spokesperson Zweli Dlamini.

This followed a fire at a substation on Tuesday which plunged the area into darkness

The areas to be affected include Kempton park extension 1, 2 and four; the CBD, Allen Grove, Adleen and Spartan.

The municipality were going to replace the transformer and panel that caught fire and repair the structure that housed them.

Dlamini said they were "very optimistic" that they would be able to meet the deadline.

About 75 percent of power had been restored to the affected areas apart from the CBD.