Truck sets off Sydney tunnel sprinklers

A truck that blocked a tunnel on Sydney's Eastern Distributor for hours has been removed but traffic remains heavy.

The thoroughfare was closed southbound at Moore Park on Thursday morning, after a truck knocked the sprinklers in the tunnel.

Police said the truck appeared to be over height and reports said its tip tray was up.

About 3pm (AEDT) authorities confirmed the truck had been removed and all southbound lanes were reopened at Dacey Avenue.

The Transport Management Centre (TMC) says traffic is still backed up to The Domain tunnel.

The southbound Eastern Distributor will close again at 9pm (AEDT) for repairs.

The truck driver was taken to St Vincent's Hospital but is not believed to be seriously injured, a police spokeswoman said.