Technical Glossary

Accredited Contractor: Health and Safety Accredited Contractors have been assessed under our procedure for approving outside contractors for their competence to make connections to public sewers.

Bond: A legally enforceable written agreement that binds a person or persons to pay a sum of money.

Combined Sewer: A sewer that collects and conveys foul sewage and surface water.

Combined Sewer overflow (CSO): A hydraulic structure that allows a combined sewer to spill flows when its capacity is exceeded (usually in the event of heavy storms). Its purpose is to limit the flow in the sewerage system downstream of the CSO so that the likelihood of sewer flooding taking place at sensitive locations is reduced.

Connection charge: A charge payable by customers to the undertaker for reasonable expenses incurred for work to connect their properties to the water mains or sewer.

Curtilage: A legal term, commonly used to mean the boundary of a property.

Defects: Includes defects in materials or construction of the Works and includes damage to the Works arising before the issue of the Final Certificate, “Defective” to be construed accordingly.

Defects Correction Period: The period commencing with the Vesting Certificate and ending with the Final Certificate.

Demarcation Chamber: An inspection chamber which identifies the end of a public lateral drain. All drainage upstream of this chamber is private. The chamber allows access for us to maintain the public lateral drain. It must be located inside the curtilage of your property.

Discharge Consents: Any discharge of surface water or effluent from a wastewater treatment works or combined sewer overflow to a watercourse requires the consent of the riparian owner. Where the watercourse is classed as ‘main river’, consent is also required from the Environment Agency.

Disposal Main: A pipe used for the conveyance of effluent to or from any sewage disposal works (Not a public sewer).

Domestic Purposes:

a) In relation to a supply of water to premises, means water supplied to those premises for drinking, washing, cooking, central heating and sanitary purposes.

b) In relation to sewerage of premises, means the removal from buildings and land appurtenant to the buildings, of the contents of lavatories, water which has been used for cooking or washing and surface water.

Drain: Health and Safety Accredited Contractors have been assessed under our procedure for approving outside contractors for their competence to make connections to public sewers.

Drainage for Domestic Sewerage Purposes: Health and Safety Accredited Contractors have been assessed under our procedure for approving outside contractors for their competence to make connections to public sewers.

Duct (used in association with a water connection): Health and Safety Accredited Contractors have been assessed under our procedure for approving outside contractors for their competence to make connections to public sewers.

Easement: A legal right over another person’s property, which may cover the laying of pipes in that land and allows access for inspection, repair and maintenance of a statutory undertaker’s asset.

Effluent: Liquid including particles of matter and other substances in suspension in the liquid.

Hydraulic Modelling: A computer-based mathematical exercise using flow information obtained by measuring flows on site. Hydraulic models are used to predict the behaviour of our systems under varying conditions.

Infrastructure: Refers to assets owned and maintained by the statutory water or sewerage undertaker.

Infrastructure Charges: A charge which we are required to impose when new connections are required and which applies to each new connection to our services. It is used to fund the cost of increasing the capacity of exiting assets.

Mandatory Build Standards (MBS): Mandatory standards laid down by Ministers which define in law, the requirements for sewer adoption agreements (see Section 104). Reference to MBS are now referred to as - Draft Welsh Government Standards for Gravity Foul Sewers and Lateral Drains. On the 1st October 2012, the Draft Standards will become Welsh Ministers Standards for Gravity Foul Sewers and Lateral Drains.

Lateral Drain: The section of drain that extends beyond the property boundary to connect to the public sewer.

Notice: normally served in the form of written word.

Public Sewer: A sewer, serving at least two properties, which has been constructed by the statutory undertaker or has been adopted as a public sewer or was classified as a public sewer prior to 1937 or transferred to the undertaker under a statutory mechanism.

Pumping Station (Sewage): An installation for pumping foul or combined sewage or surface water when an area or property cannot be drained by normal gravity sewers.

Raw water main: A water main that conveys non-potable water.

Riparian Owner: The owner of the bank and bed of a river or stream. Ownership usually extends to the centre of the river or stream, so on any given stretch of river there can be two owners, one on each bank.

Section 102: The legal mechanism within the Act, whereby the Undertaker can make a declaration for the adoption of sewerage apparatus.

Section 104 Agreement: A mandatory agreement entered into by a developer and DCWW for the adoption of sewerage apparatus.

Section 106 Authorisation: Formal approval given by DCWW which authorises a communication with the public sewerage system.

Section 185 Agreement: Agreement made between DCWW and a developer for the diversion of a public sewer (see S185 WIA for further definition).

Sewer: Conduit used for the conveyance of sewerage effluent. (Meaning within WIA) – Used for the drainage of buildings and yards appurtenant to buildings.

Sewage: Water-carried waste, in solution or suspension.

Sewerage: A system of pipes and associated infrastructure for the collection, conveyance and treatment of used water and surface water.

Statutory Sewerage Undertaker: An appointed company with duties to provide and maintain public sewers and sewerage services.

Surety: A person or body who indemnifies the undertaker and agrees to be responsible for the debt or obligation of another e.g. the corporation, partnership, or individual, executing a bond.

Surface water: Run-off from rainwater that falls onto properties (such as roofs, paths and driveways). Surface water from other sources including highways and agricultural land is not the responsibility of the sewerage undertaker.

Surface water drainage: The removal of rainwater from exterior parts of a property (such as roofs and driveways).

Trade Effluent: Trade effluent means any liquid which is produced in the course of any trade or industry carried out at premises (but it does not include sewage which is defined under drainage for domestic purposes).

Vesting Declaration: This is the legal document which confirms that an asset has been adopted as a public asset by a statutory undertaker.

Wastewater: See Sewage.

Wastewater Treatment Works: A facility for the processing and treatment of sewage

Water Industry Act 1991 (WIA91): This is the primary legislation setting out how the water companies are appointed and regulated and explaining their powers and duties.