Stonbury have recently completed an interesting project in a very sensitive and remote location.
We were contracted to carry out repairs to an existing spillway, where major erosion of grout from between the spillway stone sets had begun to make the spillway unstable.
After periods of heavy rainfall the reservoir level would come up very quickly and such was the force of water escaping down the spillway it was starting to lift and displace some of the sets.
With a start in late August, when the reservoir was at a natural low level, we first had to rake out and pressure wash the joints, between the sets, to remove loose mortar, debris and vegetation.
Re-Pointing was then carried out using a rapid setting, high strength cement mortar chosen for its environmentally friendly composition and drinking water approvals.
After a contract period of 5 weeks a total of 540 bags of mortar (13.5 tonnes) were hand placed within the spillway to ensure its future stability.
Other works included re-forming concrete spillway steps, installing new concrete haunching to the full length either side of the spillway, restabilising sections of the stone spillway walls and repairs and re-grading along sections of the 2 mile stone access track.