The slip has come down on Birdwood St in Karori.
A big Wellington suburb has lost a key commuter route because of a slip during rush hour.
Birdwood St in Karori has been partially blocked by the slip and Wellington City Council spokesman Richard MacLean said commuters should take alternative routes to avoid delays.
Cars and buses are aready delayed as the roadway is down to one lane.
Work to clear the slip is expected to start later this morning.
Wellington has been badly hit by slips in recent weeks, including two on one day that led to homes being evacuated.
MacLean said the problem was unstable and sodden ground, which got another soaking overnight.
He said more slips were possible throughout today, and drivers should stay alert.
Police responded to the scene after reports the man got into trouble in the river.