High-tech experts get grip on safety

Opus International Consultants staff Andrew Rudsdale, left, and Ian Twichel use a British pendulum tester to measure the slipperiness of footpath pavers in Rathbone St. Photo / APN

Walking on the Moon was a giant step for mankind and now the Whangarei District Council is using back to the future technology to help make it safe for people to walk on slippery paved city footpaths.

Getting a grip on how well feet stick to wet footpaths is a high-tech mission. It has to be done accurately so the ceramic pavers can be treated to avoid any repeat of the fall which broke 66-year-old amputee Wayne Wheeler's hip when he slipped over in Rathbone St in December.

Two experts from the Opus International Consultants' Whangarei laboratory, manager Ian Twichel and technician Andrew Rudsdale, yesterday used a British pendulum tester to assess the paved footpaths in Rathbone, Cameron and James Sts.

The tester has the shiny machined look possessed by many modern electronic and mechanical instruments but the way it works is not rocket science. When a device resembling a small foot swings into contact with pavers a needle points to the level of adhesion achieved with the footpath.

The pendulum testing was done on the southern side of Rathbone St yesterday after the pavers had been etched with acid to roughen their surface texture and given a deep clean wash on Tuesday night.

WDC field officer Grant Alsop said storm drain sumps in the area had been blocked during the cleaning procedure so acid-contaminated water could be captured for removal in a trailer rather than flowing into the harbour.

Anti-slip material applied to pavers on the northern side of Rathbone St was refreshed so the success of that method of increasing adhesion could be compared with acid etching.

Related experiments include pavers being sandblasted in a laboratory to see if that gives their surface better grip.

Mr Alsop and WDC infrastructure technician Nadia de la Guerre said all the tests were coming up with positive results which are expected to give the council a range of options to improve footpath safety.

After Mr Wheeler was hurt in his fall it was disclosed the WDC had received only four official complaints about slippery pavers in the previous six months.

But Northern Advocate Facebook followers had a different view with more than 900 people commenting on the pensioner's plight within 48 hours of the story of his fall being posted.

Most of the 900 claimed to have slipped on city pavers and Whangarei Mayor Sheryl Mai acknowledged the problem.

"'I have directed staff to find a solution to this safety issue, even if that means replacing the tiles."

Once tests have established the most cost-effective way to make the pavers safe a report will go to councillors to help them decide the next step.