Water & Wastewater Treatment

The Department for Food and Rural Affairs (Defra) has confirmed that Rory Stewart MP will be the minister with responsibility for water in the newly-elected Conservative government. Stewart, the MP for Penrith and the Border, has been appointed Parliamentary Under- Secretary of State at Defra, in a three- strong ministerial team along with Liz Truss (Secretary of State) and George Eustice (Minister of State). Morrison Utility Services has announced the appointment of Jim Arnold to the position of Chief Operating Officer (COO). Arnold, who has been at the company since 1998 and a Group Board Director since 2013, took up his new position on 1st June. Professor Tony Conway, former Strategic Programmes Director at United Utilities, has joined water infrastructure technology company Aquam Corp as a non-executive director. Professor Conway, who le United Utilities in March a er thirty years at the company, said he was attracted to Aquam because of its appetite for innovation. Northumbrian Water's group commercial director, Maxine Mayhew, is one of two new board appointments announced by anaerobic digestion (AD) trade body ADBA. Mayhew is joined by George Gittus, Suffolk NFU County chairman and owner of Symonds Farm Power, as ADBA strives for a diverse board representing all sectors of the industry. www.wwtonline.co.uk | WWT | JULY 2015 | 25 In the know Potentially harmful contaminants can find their way into the drinking water supply as a result of leaking water pipes, a study by researchers at the University of Sheffield has revealed. The pressure in mains water pipes usually forces water out through leaks, preventing anything else from getting in. But when there is a significant pressure drop in a damaged section of pipe, water surrounding the pipe can be sucked in through the hole. Until now, it had been assumed that only clean water from the leak would be sucked in, and that any contaminants would be ejected once pressure returned to normal. The new study has shown that groundwater from around the pipe - which o•en contains harmful contaminants - can in fact enter, remain in the pipe RESEARCH ROUND UP Propeller technology to aid developing world sanitation Researchers at Plymouth Marine Laboratory (PML) have been working with the Bill and Melinda Gates Foundation to develop a low-cost means of sterilising wastewater which could improve the lives of countless people in the Drinking water contaminant risk from leaking pipes and travel on through the network. Dynamic pressure drops happen whenever there is a sudden change in velocity, such as valve or pump failures, or sudden demands on the system, for instance when large volumes of water are required for fighting a fire. As a result of engaging with the University of Sheffield research, UK water companies are now training their field staff to limit these pressure drops taking place. Professor Joby Boxall said: "Previous studies have shown that material around water pipes contains harmful contaminants, including viruses and bacteria from faeces, so anything sucked into the network through a leak is going to include things we don't want to be drinking. Many of us will have had a dodgy tummy in the past that we couldn't quite explain, o•en putting it down to something we'd eaten. It now seems possible that some of these illnesses could have been caused not by food, but by water." The University of Sheffield research, funded by the Engineering and Physical Sciences Research Council, used a purpose-built test facility made up of 141m of mains water pipe maintained at pressures representative of UK networks. A section of pipe was damaged, and the leak enclosed by a box containing gravel into which dye was injected to simulate a contaminant. When that section was subjected to a dynamic pressure drop, up to 60ml of the coloured water was sucked into the pipe. The team was able to measure the dye at the end of the pipeline, 70m downstream, proving that the contaminant remained in and was transported through the network. Boxall added: "It's not feasible for the water industry to stop all leaks, and most of the time, leaks don't pose a risk. This is why the water industry is now focusing on preventing the pressure changes which enable contaminants to enter the system, rather than eliminating the leaks through which they enter." wwtonline.co.uk ● 27 The Pipe File: source a pipe supplier ● 31 Getting to grips: Section 104 approvals ● 34 Digging deeper: carbon management ● 37 Technically speaking: smart networks developing world. The team, in collaboration with Protein Technologies Ltd (PTL), used a simple technology involving some basic plumbing parts, a household drill and a model boat propeller, to successfully develop a tool called the vortex bioreactor. "What started out as a technology to help convert microalgae into biofuels spun off - quite literally - in the direction of global waste water sanitation", said PML Microbial Biochemist Dr Mike Allen. The system is based on the idea of exploiting a continuous vortex contained within a pipe to bring pathogens into contact with a biocidal agent: copper powder embedded in a seaweed extract. It has been shown to destroy bugs such as E.coli in only a few minutes. RISING UP 7 July CIWEM Shale Gas and Integrated Water Management conference, London 8 July Institute of Water annual conference, Cambridge 8 July SWIG Workshop on leakage, hosted by ABB, Warrington 10 July Yorkshire Water 'Data Dive' event, Leeds COMING UP

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