Drainage Terms A-Z
C
catchment
The area contributing surface water to a point on a drainage or river system, which may be divided in to sub-catchments.
cavitation
The process of implosion of air in water that is a function of high velocities, which cause damage.
Colebrook-White equation
An empirical equation relating flow to roughness and gradient of a conduit and the viscosity of the fluid.
collection system
In wastewater, a system of conduits, generally underground pipes, which receive and convey sanitary wastewater (domestic and/or industrial) and/or stormwater.
combined network
A sewer network that collects rainfall from impervious surfaces and foul water from domestic and industrial sources.
combined sewage
Foul sewage mixed with surface water, also known as storm sewage.
combined sewer
A sewer design to carry surface water and foul sewage within the same pipe.
CSO (combined sewer overflow)
An outfall from a combined sewer designed to prevent the capacity of the sewer or a sewage treatment works from being exceeded under storm flow conditions by allowing the discharge of excess diluted sewage to another sewer, tank, watercourse or some other disposal point.
consented discharges
Term used in the UK for discharges that meet conditions imposed by the appropriate public authority for potentially polluting flow to a watercourse or into the ground.
contributing area
The area of the catchment that contributes storm runoff directly to a sewerage system.
control structure
A hydraulic device to limit the rate of flow.
culvert
A covered channel or pipeline (defined by the Highway Agency as wider than 900mm) |
