River Tay Hydroelectric Project Success with Bradley & Co. and HydroNI

Bradley & Co.’s Aquaspira Pipe Recommendation: Powering Grandtully Hydroelectric Project

Following the successful completion by Bradley & Co. of major project for Northern Ireland Water using Aquaspira pipes, the contracting partnership of Bradley & Co. and HydroNI recommended the use of Aquaspira Composite Steel Reinforced pipes to their client for a new Hydroelectric Power project alongside the River Tay at Grandtully, Pitlochry.

540m of 2250mmØ Headrace Pipe and 50m of 1350mmØ Tailrace Pipe were required to complete the low head, run of river project.

1. There was a high probability that the ground would be saturated during the construction phase, making it impossible to utilise a pipe system that would require in-situ welding of joints. Only a pipe system with manufactured sealed joints could be considered.
2. For such a long run of large pipes, it was important to be able to progressively excavate, lay, and backfill the pipes efficiently.
3. Access into the site was not only very constrained in relation to space, but there were also weight limits on the most direct route to the site entrance.
4. The route of the Headrace pipe run necessitated a gradual curve with a critical design remit to ensure minimal head loss.

The spigot & socket, push-fit joints, with integral seals on Aquaspira pipes would provide an immediate sealed joint that can be completed in any weather, and even a slightly waterlogged trench, without any requirement for site welding.

The small OD of the pipes would keep excavation and backfill to a minimum, enabling the pipeline to be progressively installed and backfilled, eliminating risks from large, open excavations and piles of spoil.

Whilst each load would be optimised in terms of space (15.6m/load), the total weight of each full load of 6 pipes was only 2200Kg’s, enabling the most direct route to be taken.

The gradual radius to form the curved sections of the run was easily achieved through the use of a range of short pipe lengths that would enable minimal head loss and maximum versatility on site.