water unit

FOCUS AUDIT OF UNIT The following hints and tips have been provided to help when completing the focus audit. Obtain a site plan of your school and on it mark the position of the water meter(s). Also mark the position of all water using equipment. The standard benchmark figure for water consumption in schools is 4,000 litres per pupil per year. However most schools should be able to reach a figure of 2,000 litres, a consumption figure of 1,000 litres is possible. A reduction from 4,000 litres to 2,000 litres would result in a cost saving of over £1,500 per year for a school of 500 pupils. At current rates the cost of water and sewerage is approximately £1.50 per cubic metre (1000 litres)

	Check for leaks Check taps, toilets and overflow pipes on the outside of the building. A tap leaking at two drips per second wastes 9,500 litres of water a year (£14).A tap leaking with a 3mm diameter stream of water wastes 336,000 litres of water a year (£450). A 25mm hose or the equivalent leak wastes 35,000,000 litres of water a year (£46,500). Does your school have self-closing taps to prevent them being left on? Spray taps can save 50% of your water consumption. However both self-closing and spray taps need maintenance. Ask the site manager to read the water meter(s) last thing in the evening, when the cleaners have finished and again first thing the following morning. Any water used overnight is wasted. Where could this water have been used? Carry out the same exercise over the weekend. How much water is used in the holidays?
Look for outside taps used for watering plants and playing fields. Water-butts could be fitted to the rainwater down-pipes from the guttering for watering plants. Remember a hose pipe used for watering can use up to 4,200 litres per hour (£6)

Toilets Many toilets still have the larger 9.5 litre cistern rather than the new 7.5 litre size. "Hippo Bags" are available free of charge from Bournemouth & West Hants Water to reduce the capacity of old cisterns to the smaller size. Does your school have urinals? Do they have controls to limit flushing, especially overnight. Waterless urinals are now available that require no water at all, current cost approximately £85 (1999). If they were installed in your school how much water (money) would be saved each year. What would the pay-back period be? For example if the saving would be £170 per year the pay-back would be £85 / £170 per year = 0.5 years. Hot Water Examine the hot water pipes to taps. Long pipe runs mean that a lot of water needs to be drawn off before hot water is available. Local water heaters above the sink could reduce costs and provide a better hot water service.