Meanwhile, traffic heading north was gridlocked by a series of crashes near the Highbrook Dr onramp.
NZTA said there were three seperate crashes causing delays int he area.
Emergency services are on-site.
"Pass the scene with care and expect delays."
Earlier, Emergency services were called to the scene under the Hopetoun Bridge at 3.30pm today after the incident. The person who fell from the bridge later died, police said.
Drivers were being advised to follow the director of emergency services onsite and should expect delays, Waka Kotahi New Zealand Transport Agency said.
"Motorists are advised some affected lanes are expected to reopen around the scene as soon as possible. Police thank motorists in advance for their cooperation," a police spokesperson said.
