A river in Essex, England, which flows into the North Sea at Bradwell.
A river in Hampshire, Surrey and Berkshire, England, which joins the River Loddon; the Hampshire town of Blackwater is on this river.
A river in Wiltshire and Hampshire, England, which joins the River Test.
A village near St Austell, Cornwall.
(OS grid ref SU8559) A town in Blackwater and Hawley parish, Hart district, Hampshire, England .
(OS grid ref SZ5086) A village in Arreton parish, Isle of Wight, England .
A river in county fermanagh and county armagh, northern ireland, with a stretch on the border with county monaghan, ireland, that flows into lough neagh.
Water containing loam, tannins, etc., giving it a very dark appearance.
Blackwater fever; malaria caused by Plasmodium falciparum.
Waste from domestic toilets; water containing fecal matter.