EU Water Framework Directive (WFD)
This came into force on 23rd October 2000. It was designed to enable more effective management of the EU’s water resources in terms of tackling pollution and water conservation. The directive aims to take a holistic viewpoint of water resources, incorporating all inland, coastal and groundwater.
It also instigates the use of the river basin as the most suitable management unit, recognising that water resources cross national boundaries. The ultimate, if slightly vague, aim is that all surface and groundwater bodies achieve ‘good’ environmental status by 2015.
Potable Water
Water fit for human consumption. In the UK, mains water is potable, hence we have the slightly incongruous situation that drinking water is used to flush our toilets, water plants and wash our cars. Therefore a large quantity of potable water is needlessly wasted.
Greywater
Waste water collected from domestic activities such as baths, showers and laundry which is not contaminated with sewage. Whilst often defined as waste water, the potential for re-use of greywater means that this terminology is not entirely suitable.
Consideration needs to be made as to the mode of re-use. For instance water from laundry may have a high level of salt-based detergent which is not suitable for irrigating soil. Even water re-used for toilet flushing may need some treatment.
Blackwater
Waste water containing sewage which cannot be re-used domestically without full processing and treatment. This can also include water which contains large amounts of organic material or chemical products.
Rainwater Harvesting
As the name suggests, this is the collection and storage of rainwater from a building roof, for use in a variety of applications such as irrigation or toilet flushing. Harvested rainwater can supplement or replace greywater recycling, and as there is no opportunity for the water to be contaminated, for example from road-runoff, then it does not need to be treated, prior to use.
Water Butts
A butt (an up-ended barrel) for collecting and storing rainwater from a building roof.
SUDS
The acronym stands for Sustainable Urban Drainage System. In the past, drainage systems were designed to remove surface-water run-off from urban environments as quickly as possible, with little consideration for the quality of the water, or its impact on downstream drainage patterns. An artificial SUDS is able to manage the build-up/ run-off of surface-water by locally containing or channelling this water. It thus restricts the transfer of pollutants and protects the hydrological system.
Surface Water Attenuation
This is the process by which SUDS can lag surface run-off. Methods include: soakaways/ swales, that allow water to percolate into the ground; balancing ponds/ lakes, that are able to hold an excess of surface water; balancing tanks, which operate in a similar fashion but are constructed in sewer systems; enlargement of existing watercourses, which will allow larger quantities of water to be channelled away from the development.
Pulse metering and sub meters
A pulse meter is usually installed at the mains water supply into a building and has the ability to automatically measure the building’s water consumption at defined intervals. Sub-meters are used to measure water consumption of different systems within the building. These meters can be combined within a building management system, to manage water consumption.
