Johannesburg (and South Africa in general) has some increasingly failing infrastructure. This manifests in sometimes daily power interruptions ("load shedding"), which also cuts water supply at the same time.

Most recently the linked story has piled on another issue: explosions from underground, probably linked to gas line maintenance. A followup story[0] has a little more information, but I thought the main link's brevity might be more digestible.

[0] https://www.bbc.co.uk/news/world-africa-66256591