Tom Moir was stuck in traffic on the Harbour Bridge as a result of the crash, and said he saw a "pile-up" of cars.
"It was quite shocking really to be driving past that at that time of the morning."
He said he was held up by "nose-to-tail" traffic for 15 minutes until passing the crash site.
Police were called about a second crash involving a truck and a car just before the bridge at 6.14 this morning. It is blocking two lanes, with traffic backed up from Esmonde Rd.
The police spokesman said police were on their way, while NZTA tweeted that commuters should expect delays.
NZTA also tweeted that a third crash clear of lanes citybound on the Northern Motorway would add to the delays.
A police spokeswoman said they had been called about a crash between the Upper Harbour Highway and Tristram Ave.
There are currently no reported injuries from any of the crashes.