Water and Effluent Treatment Magazine
Issue link: https://fhpublishing.uberflip.com/i/538666
12 WET NEWS JULY 2015 G eorge Leslie is one of the contractors working on Scottish Water's £250M Glasgow Environmental Programme. The company is now working on a second phase of works to construct combined sewage overflows (CSO) aimed at handling increased rainwater flows and improving water quality in the River Clyde and its tributaries. The work forms part of Scottish Water's Glasgow Environmental Programme, the biggest investment in Glasgow's wastewater network since Victorian times. George Leslie began work two years ago on two schemes – the Shieldhall UID catchment (unsatisfactory intermittent discharge) scheme on the south side of Glasgow and at the Dalmuir UID catchment in the north of the city. George Leslie is using Kijlstra's pre-cast Vario and panel systems on the project, which has helped to fast-track work to upgrade the wastewater network in the Greater Glasgow area. Rapid Vario CSOs are pre-assembled units measuring up to 5m x 3m and comprising a base unit, four walls, a weir wall and rise units. Installation is rapid and the unit is quickly connected to drainage pipes. The panel system is for larger CSO chambers or where access does not allow the use of a pre- assembled Vario. Although still modular and based on standard components, the panel system is flexible and can be installed with either a pre-cast or an in-situ base slab. Kijlstra, which supplied pre- cast Vario and panel systems for ten combined sewage overflows during the first phase of works is now supplying products on the next phase of works on four CSO chambers. This includes: • A 12m x 3.5m panel chamber for the Greenlaw Road CSO • A 3m x 2m panel chamber at Kessington Road CSO • An 11.5m x 4m chamber at Dock Street CSO – within the Dalmuir UID. catchment • The fourth, a 5m x 2.5m Vario chamber was supplied to the Falside Road CSO, falling within the Paisley UIDs catchment, which is a further work cluster being delivered by George Leslie Scottish Water chose precast ašer trial installations demonstrated benefits in terms Project sPecs • Construct CSO chambers as part of Scottish Water's Glasgow Environmental Programme • The Glasgow Environmental Programme is transforming the city's wastewater network. Installation of CSOs is going at a fair pace, thanks to pre-cast assembly. Pre-casting a speedy approach The panel system is flexible and can be installed with either a pre-cast or an in-situ base slab ONSITE COmbInEd SEWaGE OvErfLOWS of quality, efficiency and safety. The traditional way of installing CSO chambers is to use in-situ concrete within the excavation, explains Kijlstra business manager Steve Righton. "That is slow, labour intensive and carries the health and safety risks of prolonged working within an excavation." Pre-cast components can be delivered to site and lišed into place in a few hours, allowing on-site activity to be completed very quickly and the excavation back-filled in as little as three days. "At the outset, precast units were not the usual way of constructing CSO chambers, mainly due to the bespoke nature of the sizing of the chambers to suit site conditions," says Andy MacLeod, of George Leslie. "Chambers were generally kept Your