KEY POINTS:
Security fences are being erected on Auckland motorway bridges to stop vandals from throwing objects at vehicles.
More than 50 objects thrown from bridges have hit vehicles in the past two years, prompting Transit NZ to put up permanent fences at the Alfriston Rd bridge in Manurewa and the Princes St bridge in Otahuhu.
The Princes St bridge is where 20-year-old Taupo man Chris Currie was killed in August 2005 by an 8kg concrete block hurled by a teenager since jailed for manslaughter.
Construction is well-advanced on a $300,000 pair of steel security fences on the Alfriston Rd bridge, from which at least eight potentially fatal missiles have been tossed on to the Southern Motorway.
Transit NZ said yesterday it had completed much of the structural work on the 3m-high fences and was ready to add steel mesh designed to prevent any object larger than about 5cm from being squeezed through.
The fences will be curved like the sides of a boat, to make it harder to hurl anything over the top, but Transit has decided against building solid walls for fear of making law-abiding pedestrians feel unsafe crossing the bridge.
Transit's board received a report this week identifying 28 bridges from which 56 objects hit vehicles after being dropped on Auckland motorways in the 19 months to October.
Although a second object was thrown off the Princes St bridge within weeks of Mr Currie's death in August 2005, temporary fences appear to have prevented more recurrences.
But the report, based on information from the police, listed 34 occasions on which objects were thrown from 15 bridges over the Southern Motorway.
That compares with four objects thrown on the Northern Motorway, all at Sunnynook, 10 on the Northwestern and eight on the Southwestern.
Transit network operations general manager Roly Frost told his board that apart from isolated incidents on the Tauranga and Wellington motorways, the problem appeared to be mainly confined to Auckland, the southern zone in particular.
Northern operations manager Joseph Flanagan said there were no plans to erect more security fences at this stage but that another Southern Motorway bridge, on Bairds Rd in Otara, was being closely monitored after six objects were thrown from it.
Auckland motorways police commander Dave Walker said it was fortunate that missiles such as rocks, stones and bottles in most cases bounced off vehicles or hit windscreens without penetrating them and injuring motorists or their passengers.
He was aware of just one other case, apart from Mr Currie's, in which a vehicle occupant was injured.
But the potential for more tragedies was such that the police gave top priority to reports of objects being thrown off bridges and Waitemata road policing manager John Kelly said their level of response was to include sending the Eagle helicopter overhead if available.
Two youths aged about 14 are understood to have been arrested last month after being spotted on a Transit-owned CCTV camera, allegedly scrawling graffiti and throwing stones from the Bond St bridge over the Northwestern Motorway.
Automobile Association spokesman Simon Lambourne welcomed Transit's fence-building efforts but said it should consider similarly safeguarding all 60 or so bridges on its Auckland motorway network given the potential for tragedy from every such "mindless act of violence".
"If it is a funding question, we have to ask how much a life is worth," he said.
Mr Flanagan said building more fences would mean taking money away from other safety projects.
He said safety spending accounted for 8 per cent of Transit's maintenance budget, which will run to almost $400 million in the next financial year.
That means almost $32 million will be spent on safety measures.
Motorway Madness
56 objects thrown from bridges hit cars on Auckland motorways between March 2005 and October last year:
* 34 on the Southern Motorway.
* 10 on the Northwestern.
* Eight on the Southwestern.
* Four on the Northern.
