A reminder for boaties watching SailGP in Lyttelton this weekend

The two-day event is returning to Christchurch for a second consecutive year tomorrow - with 22-thousand expected across both days.

Rules and jetski patrols have been amped up in the harbour - after a few watching boaties got too close to racing last year.

Maritime New Zealand's Matt Wood says people need to stay safe while having fun.

He says all boaties need to follow the standard rules - and travel at a safe speed.