Cuttriss Consultants carries out a diverse range of projects throughout the Wellington Region, and surveying Oriental Bay beach is one of our highlights.
Wellington City Council (WCC) completed the latest Oriental Bay beach survey, with Cuttriss Consultants and Tonkin + Taylor, to ensure the sand remains at optimal levels for the influx of beach goers over summer in Wellington.
The iconic and award-winning beach that surrounds Wellington Harbour was man made in 2004, when the Council shipped in 22,000 tonnes of sand from Golden Bay in the South Island.
“Because Oriental Bay is an artificial beach, WCC need to keep close tabs on how much the sand moves and we have a comprehensive programme in place to manage this,” says Peter Hemsley, Project Manager, Marine and Coastal, WCC.
Cuttriss undertake topographical field surveys of the sand in April and September each year, working closely with Tonkin + Taylor, the original coastal and civil designers who manage the annual monitoring and maintenance schedule for WCC.
Oriental Bay is a popular beach in summer with swimmers, families, and fitness fanatics alike. Without monitoring and regular sand shifting, sand would continue to accumulate at the western end of the beach and spill out into the harbour where it would be lost. Regular monitoring also allows the teams to identify and address potential hazards for beach users such as the condition of the beach structures and performance of the storm water outfalls.
James Moore, Civil Engineer at Tonkin +Taylor says Oriental Bay contains three artificially nourished sandy beaches; East Beach, Main Beach, and Freyberg Beach.
“The beach orientation in the harbour means that wave action causes long shore sand drift along the beach from east to west. As the beaches are artificial, there is no sand further around the coast to naturally replenish the eastern end of the beach. Monitoring allows us to assess how much sand has accumulated at the headland, and to identify the volume of sand that needs to be relocated back to the eastern end of the beach. It also allows us to track the long term trends of sand movement, and assess the future maintenance requirements for Council,” says James Moore, Tonkin +Taylor.
Cuttriss surveyors undertake the survey work to record the beach profile and to confirm the volume of sand to be relocated. When processing this data, surveyors plot the elevations of the sand from their measurements to build a 3D model of the beach. This information is also used to see how much the sand has moved compared with previous years.
Rachel Charlesworth, Graduate Surveyor, says the topographical sand measurements are not just undertaken on the sandy beach.
“We’ve carried out this monitoring since 2004 and our surveyor, Jeff Macphail, has to swim out quite far towards the fountain to get measurements, positioning a pole along section lines. The fieldwork on this job requires great communication and teamwork and we end up having a lot of fun while doing it,” says Rachel Charlesworth.
The WCC project, to enlarge the beach areas of Oriental Bay, and to develop the Freyberg Beach grass area with a modern playground, has won numerous awards including The Supreme Award – New Zealand Institute of Landscape and Architects.
To find out more about this project or our surveying work contact us.