Our water supplies are fundamental to our business. In 2006/07 Severn Trent Water's raw water storage
levels were good despite a dry summer. No hosepipe ban was imposed during the year, and storage levels at year-end
were normal for the time of year.
To meet customers' demands for water over the coming years, Severn Trent Water must ensure it has adequate water resources for the future. Its current Water Resources Plan sets out the company's water resources investment programme to 2010, and includes a development plan that goes up to 2030. To read more about the plan, click here.
During the AMP4 period 2005-2010, Severn Trent Water is increasing its activities to promote the efficient use of water by its customers. It has agreed a target with Ofwat of reducing total customer demand by 839.5 Ml/year by 2010, or 2.3Ml/d. Over the five-year period, this equates to a figure of 0.46 Ml/d per year. Severn Trent Water achieved an estimated saving of 0.5 Ml/d in 2005/06, and an estimated saving of 1.11 Ml/D in 2006/07. To meet the target water saving, it needs to deliver an additional saving of 0.69 Ml/D over the next three years. Some of Severn Trent Water's activities to promote water conservation - such as consumer education - are described in the case study on 'Promoting the efficient use of water'.
Metering is another means by which Severn Trent Water promotes water conservation, and it currently offering FROPT (free meter option) to domestic customers.
Since the Water Summit of 1997, Severn Trent Water has run a range of initiatives and promotions to encourage greater water efficiency among its customers. They include: distributing Save-a-flush cistern devices free of charge to the public; offering cut-price water butts to customers; publishing booklets on how to save water and how to have a free water meter fitted; and publishing a simple water audit guide in the Severn Trent Water billing magazine, Source, which helps customers estimate how much water they use in their home. Severn Trent Water's education programme for schools also promotes water efficiency.
Severn Trent Water initiated three trial programmes in 2006/07 to investigate water efficiency:
- A household water efficiency trial, including the audit and retrofit of water-saving devices such as shower heads, tap inserts, and cistern dual-flush systems
- A school water efficiency trial, including the audit and installation of similar technologies, plus urinal controls, within schools
- A local government partnership pilot audit scheme to investigate opportunities to promote water efficiency and save water in their buildings.
Three new research projects were also commissioned, looking at:
- Installation rates for cistern displacement devices (to improve the accuracy of Severn Trent Water's reporting)
- Installation and use of water butts (to improve the accuracy of reporting and to understand water savings associated with their use)
- Education programme impacts (to understand how Severn Trent Water's current education programme influences the attitudes and behaviours of children in relation to water use, and how the programme can be made more effective).
Severn Trent Water started a programme of internal water use audits on its office sites, with ten sites audited to date. Work on one of those sites has delivered a water saving of 70% of site water use. In 2007/08 Severn Trent Water will continue work on the trials described above. It will also explore the options for working with non-domestic customers to promote water efficiency.
C2C Services, Severn Trent Services International joint venture with Costain, provides water and wastewater services to the Ministry of Defence, at sites across the north, east and south-east of England. In 2006 it undertook a six-month leakage reduction programme at one particular major site. Flow data was logged on a 24-hour basis and the data analysed by C2C's leakage specialists. This analysis revealed that the site received almost 1 million m3 of water a year, of which 0.5 million m3 was being lost in leakage. Within the six-month period, C2C identified and fixed many external and internal leaks, and thereby reduced leakage within the system by 50%, to 0.25 million m3 annually.
C2C is also confident that leakage at the site can be reduced further, with a more comprehensive programme. At another site, C2C instigated a survey of water consumption, to determine the potential for using water-saving devices to reduce consumption. As a result of the survey, and during a five-week period, 568 water-saving devices were installed, including: aerating shower heads, urinal flush controllers, push-button taps, and tap aerators. The devices were selected by C2C because they represented industry best practice.
Data flow analysis revealed a significant impact on water consumed. Prior to installation of the devices, average daily water consumption at the site was 131m3 per day; after installation, it fell to 67m3 per day, 51% of the original figure.
C2C also provided further recommendations, from raising awareness of the need to turn off appliances, to the installation of auto shut-off valves throughout the site.
