BPC presents at the Bridges Conference in Wellington
BPC Engineering Manager Ian Pringle and Holmes NZ’s Infrastructural Manager Wayne Juno spoke to the Bridges Conference in Wellington about the benefits of lateral thinking and early collaboration to achieve better value outcomes for clients.
Among the examples they discussed was their work re-engineering the design of the Silverstream Water Bridge, a critical infrastructure upgrade for Wellington Water Ltd (WWL). The original bridge proposal was very heavy, beyond what could be easily sourced and fabricated in New Zealand and outside the capability of locally available lifting equipment, meaning it would have had to be ‘stick built’ in the volatile Te Awa Kairangi Hutt River.
Recognising the likely budget issues, BPC teamed up with Holmes to present an alternative design to WWL. “Key to our thinking was the ability to reduce the bridge’s weight so it could be built offline and lifted into position,” Ian said. “Holmes accepted the challenge!”
The result was a more constructable design that looked the same but weighed about half the original, and made of materials that could be fabricated locally.
“In total we were able to reduce an estimated 300 tonnes of steel and 1,640 tonnes of concrete from the original design,” Ian said. “This translates to an estimated carbon reduction of 1,914 tonnes of CO2 emissions.”
