Water & Wastewater Treatment Magazine
Issue link: https://fhpublishing.uberflip.com/i/1106950
www.wwtonline.co.uk | WWT | XXXX 20XX | 17 The Works T he Welsh landscape has long been used for the efficient capture and storage of water for the purposes of water treatment – something our high rainfall helps with. Surface water makes up 93% of the total water supplied to the customers of Welsh Water with significant volumes coming from open water reservoirs. Alongside this, we own and operate the Elan Valley reservoirs, which supply the West Midlands. While these structures www.wwtonline.co.uk | WWT | MAY 2019 | 17 can be considered as feats of Victorian engineering, adding to the beauty and wonder of the landscape, they can pose a significant challenge. Dwr Cymru Welsh Water, like all other water companies, needs to understand and monitor the condition of assets like these. This can be particularly challenging where individual assets can be 30 metres or more below the water surface in turbid water with low light penetration. How do you carry out a detailed survey of assets in such a hostile environment? Traditionally, we have relied on the skills of crewed dive teams, or – more recently – the use of remotely-operated vehicles (ROVs). The use of divers in such difficult environments can pose significant health and safety risks. As-built drawings of such assets can be somewhat misleading to say the least. With even less information about temporary works that may have been leŠ in situ, or undocumented abstraction points, surveying within these dark murky waters is particularly dangerous. On top of these health and safety considerations, the quality of the data returned can be lower than we hope or expect. Movement within and around these assets can easily cast up sediments resulting in virtually zero visibility and Underwater drones, also known as remotely-operated vehicles (ROVs) have proved key to the inspection of difficult-to-access reservoir assets in Wales Into the deep using advanced camera techniques BY EUAN HAMPTON, INNOVATION SCIENTIST, DWR CYMRU WELSH WATER Enhanced imagery from the underwater ROVs used by Abyss Solutions