Polypipe proves its power for Scottish hydroelectricity project

Hikers that visited the picturesque Scottish Highlands may have caught a glimpse of the rather unusual sight of Polypipe’s Ridgistorm-XL large diameter piping system being airlifted up the mountainside of the Arrochar Alps to Loch Sloy.

The mountainside is home to the Loch Sloy Dam and Sloy Reservoir, whose combined catchment area of 31 square miles is collected to supply Scottish and Southern Energy’s (SSE) Sloy Hydroelectric Power Station.

Located on the banks of Loch Lomond, the power station converts energy generated by water travelling down the mountainside from Loch Sloy above in pipework, which is then turned into useful electricity, feeding homes across Scotland.

Polypipe’s Ridgistorm-XL came to use during repair works to the existing pipework at Sloy Reservoir, which was originally installed in 1946. The system replaced part of the original pipework to collect excess water from the catchment area of the reservoir to feed the power station. 

As the UK’s leading manufacturer of sustainable drainage and water management products, Polypipe was called upon by SSE to produce a suitable water management solution that could not only provide adequate water capture, but could also be delivered and installed safely in such a remote location.

Working closely with SSE, Polypipe devised a system comprising two RIDGISTORMSeparate Catchpits and five lengths of the company’s popular Ridgistorm-XL large diameter pipe in 750mm diameters, offering storage for excess water from the catchment area.

Standing at 3.45m high, the RIDGISTORMSeparate Catchpits in 1500mm diameters were selected to provide effective separation of silt and debris from water entering the system – a vital consideration given the remoteness of the site.

Manufactured off-site under factory conditions and delivered ready to install, the RIGISTORMSeparate Catchpits designed by Polypipe’s team were engineered to feature inlets and outlets at exact heights in order to suit the site’s gradient and allow the effective flow of water through the system.

The location of the site meant that traditional vehicle access was impossible, leaving SSE with no option but to lift the system into place by helicopter. To provide stability while handling, Polypipe’s in-house Fabrications Team pre-welded Ridgistorm-XL Lifting Points to the RIDGISTORMSeparate Catchpits, allowing SSE to airlift them safely with slings into position for installation with the Ridgistorm-XL pipes.

Alasdair McDonnell, Area Supervisor at SSE, said: “While Polypipe has a reputation for providing high quality drainage solutions, it was their design expertise and the innate properties of their products that made them a natural choice for this project.

“Given the unusual location of the site, and the access difficulties that this presented, we needed a solution capable to perform and safe to airlift and install on the mountainside. Polypipe was able to do this and more, even designing their RIDGISTORMSeparate Catchpits in such a way as to limit the potential of damage when in transit on the helicopter. A company supplying a set, stock product option would have struggled to meet the challenges presented by this project.”

Emma Nicholls, Marketing Manager at Polypipe, said: “We often receive requests from clients that have unique elements, and occasionally these can include site and delivery considerations, but its not often that our engineers have to consider how to make our products fly!

“This project provided an ideal opportunity to showcase our ability to pre-fabricate unique fabrications and safety accessories, along with the benefits of plastic over traditional materials. Not only has our team been able to provide benefits at the delivery and installation phases, but they have also supplied a system that will serve a vital energy provision for years to come while protecting the natural beauty of the area being spoiled by erosion.”

For more information on Polypipe and its range of solutions, visit www.polypipe.com/civils-infrastructure/water-management-solutions