Ecological aspects of water management in Britain.
In Britain, man's alteration to river habitats began with forest clearances and continued with developments for water power and navigation. Industrialization and population increase led to extensive pollution in lowland rivers. Land drainage greatly reduced wetland habitats and, with headwater impoundment and flood protection works, further modified physical conditions. Since the middle of the twentieth century, domestic and industrial pollution have been reduced, but eutrophication and acidification trends have developed. Recreational demands have encouraged environmental improvements but have themselves become sources of damage to some aquatic ecosystems. Recently, progress in pollution control has slackened because of reduced capital investment. Organic pollution from farms has increased and the extent of groundwater contamination by agriculture and industry is under investigation. Although the total available water resource exceeds current requirements, there are continuing difficulties with geographically uneven distribution of supply and demand. The widespread loss of natural habitat which has occurred during resource development has created acute aquatic wildlife conservation problems.