Disruptive ocean swells and a tidal surge battered Pier 4 in the Inner Harbour Marina last Tuesday [21 May] causing irreparable damage.
No boats were damaged during the swell event which plagued other areas of port operation last week.
“The surge on Tuesday morning broke a pile damaging the pier beyond repair and making it unsafe to use,” says Eastland Port general manager Andrew Gaddum.
Pier 4 is a small pier in front of Lone Star Gisborne. It is one of the original Inner Harbour Marina piers, built over 25 years ago.
Three of its berths are licensed to Eastland Port company Inner Harbour Marina Ltd. The other five are licensed to private berth holders.
Four vessels were tied up at Pier 4 before the tidal surge and these have now all been moved.
Mr Gaddum says Pier 4 will now be dismantled, as even before this event occurred planning was already well underway for the replacement of both piers 4 and 5.
Long-period or infra-gravity waves caused the surge. “These long slow waves cause disruptive wave patterns in the harbour. They have the effect of moving ships alongside the port and once ships start moving the momentum is extremely dangerous for staff, the vessel and shoreside infrastructure,” he says.
Mr Gaddum says the Inner Harbour Marina is expensive to maintain because of the effects of the waves. “These waves lead to wear and tear on facilities and maintenance costs are high.”
Inner Harbour Marina and river users as well as the general public are advised to stay clear of Pier 4 while assessments are carried out.
Image caption: Eastland Port marina maintenance manager Grant Donnell was the first to notice damage to the 25-year-old Pier 4 when making his regular marina checks on Tuesday.