Heritage North Island rail viaduct wins international structural engineering award in London

The 109-year-old Makatote rail viaduct, in the central North Island. Photo / Supplied

The rejuvenation of a rail viaduct that first linked the main truck line between Auckland and Wellington more than a century ago has won an international engineering award.

Opus International Consultants received the Institution of Structural Engineers Award for Structural Heritage for the renewal of the Makatote rail viaduct.

The honour was announced in London yesterday.

The winners were chosen from a shortlist of 45 pioneering global projects which showcased the ingenuity and expertise of the engineers behind them.

The judging panel commented on the "elegant, non-intrusive detailing of the strengthening procedures", such as new tension rods hidden behind existing structural members.

This meant the heritage aspects of the viaduct have been fully maintained, while enabling increased loading from modern railway traffic.

The 109-year-old viaduct is 2262 metres long and 79m high. It has six concrete and five steel piers, according to nzhistory.govt.nz

Meanwhile, The Christchurch Arts Centre - Block C was also commended in the awards Structural Heritage category, and the seismic strengthening of the Majestic Centre in Wellington, received a commendation in the Sustainability category.

Both projects were completed by engineers Holmes Consulting.

A diverse range of structures, from temples to tourist attractions, were recognised across 14 categories in the awards, which are in their 50th year.

The Supreme Award winner was the British Airways i360 in Brighton.

The British Airways i360 in Brighton, United Kingdom. Photo / Supplied