Llyn Aled, Wales
The upstream face of the dam at Llyn Aled Isaf was protected by stone pitching which had weathered and been damaged over the years to leave inadequate protection to the embankment.
Hesselberg Hydro installed a protection layer of OSA over the existing stone pitching to the main dam and both sides of the saddle dam. The upstream face of the dam at Llyn Aled Isaf was protected by stone pitching which had weathered and been damaged over the years to leave inadequate protection to the embankment.
Hesselberg Hydro installed a protection layer of OSA over the existing stone pitching to the main dam and both sides of the saddle dam.
A total of 3,000 m2 OSA was placed – a 125mm thick layer plus approximately 100kg/m2 OSA was used to fill voids in the loose, open surface.
Hot-poured bituminous mastic was used to seal the edges of the repairs and to stabilise the loose rock lower down the slope beyond the reach of the excavator.