Designed by: Department of Parks & Wildlife (DPAW), GHD
Client: DPAW, BGC, Boyd Metal Industries
Location: Tondirrup National Park, Albany
Timeframe: Completed March 2016
The Harley Dykstra team in Albany have been involved in this project since the original feature survey in early 2005 which was used along with some highly detailed follow up surveys to develop the concept plan and finally construction drawings for the new walkways and lookouts. Construction work began in November 2014 and was completed in March 2016. During construction many other detailed feature surveys were done to ensure there would be no clashes when the structural steel elements for the elevated walkway and lookout were installed.
A critical part of the construction phase were the many ‘Prefabrication’ surveys done by Chris VanderPlas and David MacInnes in Perth. These surveys involved checking and adjusting the final welding setup of the five large stainless steel beams that now hold the main cantilevered lookout in place. It was critical that these beams were manufactured to design so that they would fit exactly between the pre-installed anchor points on site.
The final stages of this work took place in late 2015 and early 2016. The five lookout beams were individually lifted into place by a 100 ton crane. Their final position was monitored and adjusted by sighting small adhesive targets fixed to their cantilevered ends. This was done with a Trimble S6 Total Station from the far side of the Gap, and was important to ensure that the beam ends were all at the same height and spaced so that the cross-member joists would fit between them.
At the completion of the project Harley Dykstra received a very nice thankyou letter from DPAW acknowledging that our “attention to detail with all aspects of survey on and off site was critical in successfully delivering this project.”
Some of the challenges faced by the Harley Dykstra team during this project included:
- Ensuring that the beams prefabricated in Perth would match design and fit between the anchor points installed on site;
- Maintaining high accuracy in less than ideal conditions;
- Set out for intricate concrete pathway works, including stainless steel inlays and etched patterns; and
- Communication on-site with the numerous sub-contractors.
This project has resulted in new walkways and lookouts for the Gap and Natural Bridge area that have received overwhelmingly positive feedback from the public and will be a tourist attraction for Albany for many years to come.