Martin Wilson is Managing Director of Abseil Access, a company he started 30 years ago. With offices in Wellington, Christchurch, Nelson and New Plymouth, the business specialises in bridge design and building, slope stabilisation and industrial maintenance.
Abseil Access has completed the end-to-end process of design, engineering, local approvals, and construction of swing bridges and suspension bridges across some of the most stunning parts of New Zealand and the Pacific Islands.
Having designed and built all the bridges on the nearby Old Ghost Road, they were asked to assist with the Kawatiri Coastal Trail bridges, having also worked previously with Buller District Council, Westreef and Dextera.
No matter how remote the location, or challenging the design, their passionate team deliver innovative, high quality, fully engineered solutions. This has seen them recognised as the market leader in pedestrian and cycle trail suspension bridge and swing bridge design, engineering, and construction.
We caught up with Martin, who is also a qualified engineer, and active mountain climber who likes to get his hands dirty, to hear more about the building process, the challenges they face, and what the recent Award for the Waitakere Nile River bridge means to them.
Photo credit: Abseil Access – Waitakere Nile River Suspension Bridge
You work closely with clients to understand their needs and produce the perfect solution. Tell us about your design, engineering and construction process.
We have now built 90 bridges. Most of these are the full design, engineering and consents package. We are the only firm in New Zealand offering this one-stop shop solution. We have several standard designs for bridges based on length, width, look and capacity. I can visit the site, measure up and get a costed solution to the client quickly.
We are also good at working alongside the trail builders, to get the best efficiency on equipment. Overall, we aim to provide an extremely cost-effective solution with minimal fuss. It’s part of the greater plan to get New Zealand going with cycle trails everywhere.
With the boom in cycle tourism in recent years, has the bridge building aspect of the business become more significant?
Yes, we started with one bridge per year in 2006 & 2007 and then 11 in 2020, 13 in 2021 and 9 so far across 2022. There are cycle trails getting built everywhere, and we are contacted by the Trusts to assist with the bridge builds. At this stage, we have 57 bridges on the books to do in the next five years.
Photo credit: Abseil Access – Construction of the Nile River Bridge
The construction process for your teams isn’t a usual day job. What are the main challenges they face on a bridge build?
The builds are always done with a small team of 3 or 4. In the team the crew needs to be multi-disciplined. We do the survey ourselves, the geo-tech investigation, the set out, the digging (with our own flyable digger), the steel cages, and the concrete pour. The team pre-make all the timber (towers, transom and decking). The towers are raised using a helicopter or one of our three crane trucks.
Often the team will live together near the site. Sometimes in a Department of Conservation hut or even camping. We also have a flyable accommodation. The team must get on well with each other, cook as team, and work in all weather, even snow.
How does the addition of bridges along our cycle trails contribute to the Trail user experience? And what is their expected lifespan?
The bridges are always made to meet the New Zealand construction codes with a minimum life of 25 years, and some extended to 50 years. They are often the popular stopping points on the trails and get photographed. They are always in beautiful locations and are built to withstand high water (100-year flood levels).
Photo credit: Abseil Access
How sustainable are the bridges?
The bridges do require yearly inspections, but this can often be done by a local. We provide an inspection manual and instructions. We try to make the bridge sustainable by using timber for decking, handrails and towers. Sometimes we have to use steel for the bigger spans.
The Waitakere Nile River Bridge was the recent recipient of the Small/Medium Structure Award at the NZ Bridges 2022 Awards. What does this recognition of your structures which complement New Zealand’s cycling and walking trails mean to you and your teams?
We are incredibly happy. It is one of our best bridges, and so it was the obvious choice when we were asked to enter a structure. I’m also really pleased it is with the Kawatiri Coastal Trail Trust, and the other locals who we worked with. Jim McIIraif from Westreef, Glenn Irving, Eric de Boer from Buller District Council, Phil Rossiter from Dexterra, and Stu Henley. They are all a great team, and I’m stoked to be a part of it all.
We have designed and bought all materials for the next two bridges in the middle of the Trail. These bridges are planned to be built this year, by the same crew that built the Nile River bridge, and the Martins Creek bridge.
We currently have quite a West Coast bridge record, with 18 bridges on the Old Ghost Road, 4 on the Paparoa Track, 3 on the West Coast Wilderness Trail, 4 on the Heaphy Track (plus major repairs and works on 6 others). Wilderness bridges for DoC on the Copeland Track, Perth River, Whataroa, Moeraki, Pancake Rocks, Routeburn Track, Marian Creek Walkway, and 4 on the Milford Track.
Photo credit: Abseil Access – Martins Creek Suspension Bridge
You can experience the Martins Creek Suspension bridge on the Pūwaha Section. With its towering ship like masts, it offers elevated views of the wetlands, wildlife and wider West Coast scenery. The bridge is named after the Martin family who were the first permanent Pākehā settlers in the Buller District, establishing the first farm in 1865.
The Waitakere Nile River Suspension bridge can be found at the start of the 1km Waitakere Section between the Nile River and Charleston. Charleston settlers funded the construction of the original log bridge which opened to traffic in 1867. A third bridge in 1875 served traffic for 65 years, and the abutments of this bridge were used for the new suspension bridge.