C

Catchment

The total area of surrounding land that slopes towards and drains into a river (4)

Ceramic filtration

Filtration of water using a ceramic pot (10)

Cloth filtration

A means of removing solids from water using fine cotton cloth (10)

Coagulant

Chemical used in water treatment to neutralise the charge on fine particles (5)

Coagulation

Neutralisation of the electrical charge of particles by using a coagulant (5)

Coarse screens

(in water treatment) steel bars that have a spacing of 5–15 cm (5)

Compliance monitoring

Analysis of water to check that it is within required standards (8)

Concentration

Amount of a substance in a given volume of water or air (2)

Contact time

Length of time for which the water undergoing treatment is exposed to a disinfectant (5)

Corrosion

Process whereby a metal gets weaker due to a reaction with its environment (7)

Criticality

Degree of importance (6)