Riccarton racecourse will feature the rare sight of its public grandstand sitting empty during this year's Grand National Carnival.
The Canterbury Jockey Club has closed the grandstand following advice from its engineers and lawyers.
''They want to err on the side of caution by not having Joe Public in there,'' chief executive Tim Mills said.
''You just have to take the safety-first approach.''
The nearly 100-year-old grandstand has been the subject of regular and rigorous inspection since Canterbury's 2011 earthquakes.
Recent investigations revealed additional information that led to the grandstand being closed, Mills said.
The Canterbury Jockey Club has told its members the building is not at imminent risk of collapse under gravity loads, but earthquake damage has increased the risk of collapse in the event of a ''design level earthquake''.
The grandstand could be reopened after negotiations between the club, its insurers and engineers are complete.
''At this stage we are still working through the repair methodologies, the repair strategies, working with two sets of engineers thrashing things out.
''Hopefully, sooner rather than later it will come to a head and we will know where we are going and what we are doing.''
The closure of the grandstand is not expected to have a significant effect on the Grand National Carnival.
The Canterbury Jockey Club expects the annual feature meeting to attract a good contingent of North Island horses, as well as Otago and Southland raiders.
''We are looking forward to a strong representation of horses from Invercargill to Whangarei.
''We have been talking to the Oulaghans and the Myers and the Duncans and the Rayners and all of that crew that make it a feature.''
Otago's star hurdler, Jackfrost, is set to have his final hitout before the Grand National Carnival at Timaru on Friday.
The Brian and Shane Anderton horse is the topweight among 12 nominations for a 3000m restricted open hurdle.
Leading Southern steeplechaser Tai Ho is among 10 horses nominated for Friday's 4280m restricted open steeplechase.
