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Loch Drunkie is retained by two earth dams built in 1859. The outlet pipe is a 24 in dia. cast iron pipe through the highest part of the east dam with downstream control only. Although no record drawings exist, it is considered that the pipe is laid directly within the foundation or embankment fill and the presence of any concrete surround is unlikely. The pipe is over 160 years old and, due to the valve arrangement, is always subject to internal pressure from the reservoir. The east dam was inaccessible with no vehicular access to within 500 m. In the 2014 Statutory Report, a recommendation in the interest of safety was made to ascertain the condition of the outlet pipe and carry out any works deemed to be required to reduce any potential threats posed to the safety of the dam. This paper describes the series of investigations and subsequent pipe lining works that were carried out at the reservoir. Due to concerns regarding the integrity of the pipe, all investigations and pipe lining works had to be carried out with the reservoir at top water level to ensure the internal pressure to the pipe was maintained throughout.

In December 2020, the British Dam Society (BDS) conducted a year-end survey of both its individual and corporate members. The survey asked that members rate how much they agreed with a series of statements and were given the opportunity to submit additional comments. The survey contained 14 questions for individual members and three questions for corporate members. This paper presents the results of the survey along with feedback from the BDS Committee.

At Talla Reservoir the main scour outlet was impracticable to operate due to its arrangement; discharge would impinge at high velocity against the adjacent supply pipe stack, which carries a substantial part of the water supply to Edinburgh. The scour capacity available without the use of the main scour arrangement was deemed inadequate. Works were carried out to amend the arrangement of the scour pipe by installing specially manufactured steel bends and tapers to discharge reservoir water through a diffuser pipe located downstream of the existing supply stack. This paper describes the design, installation and commissioning of the works including the principal considerations and challenges that were overcome during the design process.