D-E
Defluoridation
Removal of excess fluoride from water (5)
Diffuse pollution
Pollution from non-point sources (4)
Diffusion
Process by which something moves naturally from a region of high concentration to one of low concentration (11)
Disease outbreak
Unexpected rise in the number of cases of a disease (14)
Disinfection
Elimination of micro-organisms that can cause disease (5)
Distribution mains
Pipes that take water from a service reservoir to other areas for use (1)
Drinking water ladder
Steps in improvement of quality of water supply (3)
Drinking water standards
Set of limits for the amounts of specified substances in drinking water (9)
Drip-feed irrigation
Form of irrigation where water is put at the base of a plant, using narrow pipes (1)
Drought
Lack of rain that lasts for a long period of time (14)
Emergencies
Sudden, unexpected, hazardous events that call for immediate action (14)
Enteric
Concerned with the intestine (part of the body where food is digested) (2)
Eutrophication
Process by which nutrients, especially phosphates and nitrates from agricultural or other activities, build up in a water body causing excessive plant growth and eventual decay, resulting in depletion of oxygen in the water (4)