Contamination below the maximum set limits can still be pollution. A dry watercourse is controlled water, as are streams and drains. Pollution is an ordinary English word defined in the Oxford English Dictionary as ‘to make physically impure, foul or filthy, to dirty, stain, taint or re-foul’. It is therefore not necessary to show that water is harmed to show that it is polluted.
Gazette 15-Mar-1995, Times 08-Feb-1995,  Env L R 258
Water Resources Act 1991 85(1)
England and Wales
Cited – Express Ltd v The Environment Agency QBD 15-Jul-2004
The dairy appealed its conviction for allowing cream to enter a brook from the land of its customer.
Held: Polluting matter did not need to be itself noxious or poisonous, it was enough that it stained or tinted the water as did cream. Though . .
These lists may be incomplete.
Updated: 10 April 2021; Ref: scu.86575