Glossary of Terms > Water
Average Daily Water Use
A standard measure to measure water volumes in different time periods.
BOD (Biological Oxygen Demand)
The amount of oxygen consumed by bacteria while decomposing organic matter under aerobic conditions.
BOD5
The biochemical oxygen demand of wastewater during decomposition occurring over a 5-day period. A measure of the organic content of wastewater.
Borehole
A well from which water is extracted.
Chemical Oxygen Demand
A measure of the oxygen-consuming capacity of inorganic and organic matter present in wastewater. Measured in milligrams per litre.
Combination Meter
A type of meter that incorporates two meters: one to measure larger flowrates, the other to measure low flowrates. Sometimes known as a compound water meter.
Conductivity
A measure of the ability of water to conduct an electrical current. Used as a surrogate for the amount of dissolved solids or salt content in the water. Also see TDS.
Consumption Benchmark
A calculated figure to determine the volume of water used relative to an output such as personnel numbers, widgets made, hotel rooms occupied, etc.
Cubic Metre (m³)
The standard metric measurement of water volume.
1 m³ = 1000 litres
1 m³ = 220 Gallons.
1 m³ weighs 1 metric tonne
Descending Block Tariff
Large User Tariff whereby unit rates are reduced as volume increases.
Domestic Sewerage
Discharge of sewage from domestic facilities, e.g. canteen, toilets, showers, etc.
Effluent Discharge Meter
Metering device used to measure the volume of trade effluent discharged from a site. Also known as flume meters, V notch weir meters, outfall meters.
Environment Agency
The environmental regulatory body in England and Wales.
Filtration
Processes that physically removes particles from water.
Flow Logger
An electronic device to measure and record the flow of water through a meter.
Flume meters
See Effluent Discharge Meter.
Gallon
The standard imperial measurement of water volume.
1 Gallon = 4.546 litres 1 Gallon weighs 10 pounds
Highway Drainage Charges
Charges levied by sewerage undertakers for collection and disposal of surface water from public roads and highways. May often be incorporated with surface water drainage charges
Inferential Meter
A water meter usually found on larger diameter or bulk supplies. Sometimes known as a Turbine meter, Woltex meter, Helix meter, Helical Vane meter, Bulk flow meter
Inset Appointment
Competition mechanism (England & Wales) that permits a water or sewerage undertaker to provide services within the area of another water or sewerage undertaker. Generally only applies to large volume users.
Litre
A standard metric measurement of water volume.
1 litre
Approximately 0.22 Gallons. 1 litre weighs 1 kilogramme.
Megalitre
1000 Cubic Metres.
mg/litre (milligrams per litre)
Another way of expressing parts per million.
Modgen Formula
A method of calculating a volumetric charge for trade effluent. The formula links charges to individual characteristics (such as strength) of an effluent discharge.
Noise Leakage Correlation
A method of using the noise generated by a leak to accurately pinpoint the position of the leak.
Non - potable water
Water that is not fit for human consumption.
Non Return to Sewer Allowance
An allowance granted by sewerage companies that reflects the volume of water that is not returned to foul sewer e.g. from water in product, evaporation, etc.
OFWAT
The Office of Water Services: The regulator for water and sewerage companies in England & Wales. See also Scottish Environmental Protection Agency.
Outfall meters
See Effluent Discharge Meter.
Parts per million
Another way of expressing milligrams per litre.
pH
A logarithmic measure of acidity and alkalinity for water and for trade effluent.
Potable Water
Mains water supplied by a water undertaker or water that is fit for human consumption.
Pressure Logger
An electronic device to measure and record water pressure.
Rotary Piston Meter
A type of meter used for measuring flowrates and volume to smaller premises. Also known as positive displacement meter or volumetric meter
Scottish Environmental Protection Agency
The environmental regulatory body in Scotland
Sewerage Standing Charge
A fixed charge for discharge of sewerage. May be relative to meter diameter or to discharge flowrate. May include a component value for discharge of surface water
Sewerage Undertaker
A sewerage collection and treatment company.
Surface Water
Rainwater which falls on roofs, car parks and other areas of hardstanding.
Surface Water Charge
A charge levied by sewerage undertakers for collection and disposal of surface water.
Suspended Solids or Settleable Solids
Solid organic or inorganic particles that are held in suspension in a solution. Measured in milligrams per litre.
TDS - Total Dissolved Solids
A measure of mineral content dissolved in water measured in parts per million.
Trade Effluent
Liquid waste, with or without particles in suspension, derived from a trade process.
Trade Effluent Sample
A sample of effluent taken by a sewerage company to determine content of the effluent. Usually taken for charging or consent compliance purposes.
Turbidity
The measure of the scattering effect that suspended solids have on light; the higher the intensity of scattered light, the higher the turbidity.
Volatile Organic Compounds (VOC's)
Compound that have high vapour pressure and low water solubility. VOCs typically are industrial solvents, constituents in petroleum fuel products, or by-products produced by chlorination in water treatment.
Water Meter
A device for measuring water volume.
Water Standing Charge
A fixed charge for the provision of a metered water supply. May or may not be relative to meter diameter.
Water Undertaker
A water supply company.
