Dr Keith White2026-05-202026-05-20https://dspace.academy.edu.ly/handle/123456789/2073Pollution is very broad term that has many different meanings; however, it can be considered as anthropogenic concept which results from human activities (Mason 2003). On the other hand, similar effects can result from natural environmental changes, such as biogeochemical cycling of elements or ecosystem processes. There is a broad definition quoted by Holdgate (1979) explaining pollution as “The introduction by man into the environment of substances or energy liable to cause hazards to human health, harm to living resources and ecological systems, damage to structure or amenity, or interference with legitimate uses of the environment''. Thus, pollution is defined on the basis on anthropogenic-induced introduction of substances or energy.One of the most prominent topographical features of Greater Manchester is the River Irwell which drains much of the conurbation. Arguably the most important part of its catchment in terms of the local economy and amenity is the lower Irwell which includes the upper reaches of the Manchester Ship Canal (MSC). This lower Irwell is highly modified, being subject to re-engineering to facilitate navigation and flood control. It also drains industrialised and densely populated parts of Greater Manchester and is therefore subject to organic and inorganic pollution from storm water overflows, waste water treatment works and industrial effluent.Water Quality and Ecology of Heavily