Broken legs and optional hard hats: Memories of construction in the 1970s
Although nearly 50 years have passed, Harry Knights can still recall the screams of pain from a fellow labourer who had broken both legs and was swinging upside down from formwork at the Warrnambool Water Treatment Plant (WTP).
They’d been part of a construction crew, pouring concrete for the walls of the huge water storage tanks when the formwork collapsed, leaving the man suspended high above the ground. In a rescue exercise that seemed to take forever, the single crane on site had to be manoeuvred into position to brace the structure, allowing the worker to be freed and taken to hospital.
Harry, his brother-in-law and concreter Gary Speed, and Don Carter, a former Warrnambool City Council water and sewerage engineer (who was in charge of the project) met on-site at the WTP last week to share some photos and memories of the project.
The two tanks – the 34-megalitre raw water storage and a 20-megalitre clear water storage – were designed with trapezoidal walls, reducing the amount of concrete required without compromising strength.
Anchor bolts were driven about 18 feet (5.5 metres) into the ground and then stress-tested. When one failed, the crew attempted to fill the void with concrete slurry. It required truckloads of slurry for days and days until they finally realised the bolt had been drilled into a cavern below the site.
Construction took place using slipforming, with a 14-metre long formwork lifted manually with hydraulic jacks. It was wound up around 2.5 centimetres every five minutes as the concrete was continuously poured. The concrete was trucked onto site and hoisted up in two barrows at a time.
Gary said nobody really knew what they were doing during the first pour, which took around 24 hours to complete. In the end, they were back to just five or six hours.
The crew worked in two shifts for 24 hours a day, seven days a week “until they cut it back to six days as everyone was getting tired”, he recalled.
Unfortunately, the formwork collapse wasn’t the only accident that occurred. There was very little regard for safety back in the late 1970s although “we wore hard hats sometimes”, Harry said.
“I was carted off to hospital twice.” The first time was when scaffolding fell and Harry landed on his back, striking a rock and injuring his shoulders. In the second incident, he was carrying an armful of tools, including a welding mask, when his feet slipped off the top rung of a ladder fixed to the wall, smashing both wrists.
The walls of the tanks were completed before the team started work on the floors and then the roof of the clear water storage. Once completed, the tanks were filled with water for leak testing and then emptied. It wasn’t until a few locals arrived the site to complain, the crew realised they’d inadvertently flooded all the houses further down the hill.
With the support of a workmate, Harry’s final task was to repair any cracks in the wall with a sealing agent. Rather than equip them with a boat, they were sent out on a raft crafted from a tractor tube and some timber planks (and not a life jacket in sight!). As the water level in the raw water storage dropped during the day, they had to row around to find the cracks and seal them: “Such a boring job!”
Prior to their construction, Warrnambool had been subjected to regular water restrictions and the council (then in charge of water and sewerage for the city) had been receiving complaints about dirty water for more than 20 years.
Huge thanks to Don, Gary and Harry for their time and for sharing some stories of a remarkable project that resulted in a safe and secure water supply for future generations.
