Steam Pipe Line Tunnel
(Incorrectly dated photos from 1947)
217609PD Construction of a tunnel for steam lines from
East Perth Power Station to Royal Perth Hospital, 1941
217610PD Construction of a tunnel for steam lines from
East Perth Power Station to Royal Perth Hospital, 1941
In April 1948, the Public Works Department of Western Australia completed construction of a 1.5-mile-long steam pipeline linking East Perth Power Station to Royal Perth Hospital. The pipeline became operational the following month, after a 15-month construction period that employed an average of 150 full-time workers.
Planning and Construction
The contract to supply and insulate the steam and condensate pipelines was awarded to Bradford Insulation Pty Ltd, a Sydney-based firm, on 10 December 1946. The contract was valued at £10,608—approximately $468,100 in today’s currency.
The pipeline was engineered to handle a maximum steam flow of 25,000 lbs per hour, with additional capacity planned for future extensions, including heating the proposed Government Offices (likely the Treasury Buildings) and a state laundry facility in East Perth (which was never built). During testing in April 1948, the system demonstrated the ability to deliver 56,000 lbs of steam per hour.
The pipeline’s construction required:
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200 tons of steel piping lay in a reinforced concrete box culvert to protect against groundwater.
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A total of 4,600 cubic yards of concrete.
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A tunnel width of 4 feet 6 inches (137 cm).
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140 tons of mineral wool insulation (also known as slag wool), 4.5 inches thick, secured with mesh netting and steel straps.
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A 0.5-inch-thick layer of insulation cement mixed with slag wool.
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30 tons of 0.3-inch-thick Zincanneal sheeting (zinc/iron alloy-coated steel) to minimise heat loss.
To accommodate thermal expansion and contraction, the steam pipe was mounted on rollers, allowing it to move freely in either direction.
How It Worked
The steam generated at East Perth Power Station was used at Royal Perth Hospital for sterilisation, cooking, heating and was planned to support a steam jet refrigeration plant to provide chilled water for air conditioning.
Heat from condensate (steam that had condensed back into water) was recovered for use in the hospital’s hot water system and laundry.
Instead of building a 200-foot smoke stack on hospital grounds, which would have taken up significant space and required ongoing maintenance, the steam pipeline provided a compact and cost-effective alternative.
Steam Traps and Condensate Return
The pipeline used steam traps to remove condensate and maintain dry steam. The recovered water returned via a condensate line to the Machinery Room at Royal Perth Hospital, ensuring efficient heat recovery and system operation.
Water Hammer Incident (1951)
In June 1951, issues arose due to water hammer—a phenomenon caused by sudden pressure changes in a piping system. With steam temperatures reaching nearly 315°C, the hospital’s Superintendent Engineer raised concerns about the safety risks. It was suspected that the newly opened South Fremantle Power Station was supplying lower-quality steam, contributing to the problem.
At the time, Royal Perth Hospital was paying around £1,400 per month (about $46,780 today), with approximately £256 worth of steam not being received due to losses.
Decline and Legacy
Anecdotal reports mention a Royal Perth Hospital janitor walking the pipeline at least once a year to conduct safety and maintenance checks.
Control gear inside East Perth Power Station can still be seen with labels like ‘RPH No.1’.
Additionally, a smaller 5-inch steam line supplied steam to the East Perth Gas Works, though very little documentation exists about its operation.
Today, most of the 4 feet 6 inch pipeline tunnel has been either filled in or repurposed for other utilities, leaving behind only fragments of this once-innovative energy solution.
