SECTION 4
further investigation is required. NOTE: If you have urinals on site with no flush control, water will be used out-of-hours. Overflows are usually due to poor control and most run to drain without being measured. Leaks and overflows can arise from:
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perished tap washers;
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worn (cistern) valves;
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corroded pipework;
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flooded floats in water break tanks and cisterns.
The following steps are usually sufficient to avoid overflows and identify leaks:
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make sure overflow outlets are visible;
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carry out regular checks on overflows, pipework and valves;
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put a system in place for reporting leaks and faults;
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install simple level sensors and on/off control systems for pumps;
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install shut-off valves (easy to use);
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monitor meter readings.
Isolation Of Water Supply Identify where the isolation points are. Consider replacing gate valves or stopcocks with quarter turn ball valves or isolator valves. This will provide a clearer indication of whether the valve is open or closed.
Water Pressure High water pressure can:
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result in excessive water consumption;
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cause or exacerbate leakage;
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place additional (unnecessary) wear and tear on the distribution system.
To meet minimum pressure and flow requirements, water mains are usually operated at pressures between 2 and 4 bar (200 and 400 kPa), although currently there is no stipulated maximum mains pressure limit. In some cases, higher water pressure than necessary may be delivered to the lower floors of tall buildings. This can occur where the water is supplied under gravity from a break tank in the roof void or where distribution systems are
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equipped with booster pumps to ensure adequate pressure is delivered to the top floors of tall buildings. In these cases,