Traffic restrictions remain in place on Riddiford Bridge on Te Awaiti Rd near Tora after concerning cracks in the supporting piers were identified before Christmas.
The cracks were discovered during a visual inspection on December 12, prompting South Wairarapa District Council [SWDC] to impose restrictions on December 13 that limited its use to vehicles weighing 3500kg or less, travelling at a speed of no more than 10kmh.
Although a secondary report on December 14 endorsed these restrictions as “appropriate and reasonable”, SWDC subsequently raised the vehicle weight restriction to 20,000kg after advice from the initial assessor.
SWDC group manager Stefan Corbett has confirmed to the Times-Age that the council intends to commission a full assessment early next year, and the current traffic restrictions will remain in place until this is done.
“[The cracks] were not a real issue in 2019 but have worsened significantly in the past 24 months,” Corbett said.
“The damage is significant enough for us to temporarily reduce the weight crossing the bridge as a precautionary public safety measure.”
The report released on December 14 notes that there was no specific mention of a vertical crack in Pier Three during an inspection in May 2017, although a “February 2019 report notes a wide and long vertical crack in the upstream edge of Pier Three with the crack measuring 10mm wide”.
The width of the crack has now increased to 20mm, with an unknown depth.
“No reinforcement was visible in the crack, so we could not determine whether the crack extends into the reinforced core of the pier or is just in the cover concrete,” the report said.
Corbett confirmed that bridges in South Wairarapa have a basic visual inspection every year, a more detailed examination every two years, and a structural assessment every six years.