City Power said there is a spike in the number of faults reported due to ongoing heavy rains.
More than 2,700 outage calls were logged on Sunday evening alone.
Lightning struck the Northcliff Water tower, which affected supply and interrupted operations.
The weather service has issued a level 4 warning for heavy rains in Gauteng for Tuesday.
City Power’s Isaac Mangena said “the wet conditions have worsened outages and are hampering restoration efforts as teams battle to access areas that remain water-logged. The prolonged rainfall continues to affect our ability to respond timeously to faults and maintain a stable electricity supply as technicians navigate hazardous terrain, limited access routes and unsafe working environments.”
He also said road closures synonymous with recent heavy rains, also hamper efforts of digging, required to repair underground cables.
A chunk of faults were reported in Roodepoort (906), Reuven (402), another 309 calls came from Cheltondale, Linksfield, Orange Grove, Sydenham, Sandringham, Bez-Valley, Cyrildene, and Deweshof.
Hursthill had 317 open calls, Randburg (288), Lenasia (253), Alexandra (209) and Midrand (99).
Important number: Outage queries must be logged via citypower.mobi or by calling 011 490 7484.