Water & Wastewater Treatment Magazine
Issue link: https://fhpublishing.uberflip.com/i/929831
16 | FEBRUARY 2018 | WWT | www.wwtonline.co.uk with importing water from elsewhere. Offsite building allowed parallel working, with the resulting shorter programme of onsite works cutting project timescales and costs. The project realised a 5% saving on the original project CAPEX, with savings of more than £110,000. The benefits continued with reduced HSE construction risk, as much of the construction work took place in a controlled indoor environment. The offsite construction process also wastes fewer raw materials and has a smaller overall carbon footprint too. The development is the largest off-site construction project the water industry has yet seen and stands out in the wider construction sector too. Greg Cameron, Business Lead at Affinity Water said: "The project is the first time we have applied off site build on this scale and has provided numerous benefits. The factory build has allowed us to test equipment and soŽware before it arrives to site, increasing confidence that it will work first time. This technique has reduced the overall construction programme and helped minimise disruption to local residents." The kiosk also includes the new main site Motor Control Centre that powers not only the skid equipment, but also the new borehole pumps and existing surge vessel. Considering the breadth of services it con- tains, the 20m-long, 4.2m-wide and 3.4m- tall skid is extremely compact compared to conventional onsite installations. All equipment was installed, electri- cally connected and every process tested and commissioned before the treatment plant went anywhere near the site. Once complete, it was transported to site, put into position and linked to power and pip- ing – all in a single day. Mounting the treatment plant on precast concrete supports instead of a poured concrete base further simplified and speeded both onsite works and the installation process. AŽer arriving onsite, the kiosk simply had to be craned onto the supports. This project also saw Nomenca intro- duce Saint Gobain's Universal Rapid Vi Pipe to the UK. The design's anchored joints employ an innovative gasket and steel teeth to withstand the thrust forces that high water pressures produce around bends. That removes the need for bulky concrete anchor blocks, accelerating in- stallation, minimising space requirements and, again, reducing costs. The results The technical innovations drove a number of financial, environmental, safety and time-saving benefits for Affinity Water. The survey techniques produced an ac- curate digital site plan extremely quickly, while Level 2 BIM technology enabled collaborative working at all stages of the project. The use of 3D modelling made sure assets built off site fitted with existing site piping and equipment. Testing the treatment plant to high tolerances and identifying and dealing with minor issues offsite all contributed to the success of the project. On installation day, the kiosk lined up within 5mm of the existing pipework. All upgrading works took place while the legacy plant continued to operate as normal. Only a single brief shutdown was needed to connect the new services, keeping the water supply running to thousands of Essex residents while minimising noise and disruption. The rapid connection also avoided the potentially vast extra costs associated The Works: offsite construction