lough leane is approximately in size and is by far the largest of the three lakes. it is also the largest body of fresh water in the region. it is also the lake richest in nutrients. it has become eutrophic as a result of phosphates from agricultural and domestic pollution entering lough leane reedbed, an important habitat on the edge of lough leane. this nutrient enrichment has caused several algal blooms in recent years. the blooms have not yet had a severe effect on the lake's ecosystem. to prevent further pollution causing a permanent change in the lake's ecosystem, a review of land use in the catchment area is being carried out. water quality in the lake appears to have improved since phosphates were removed from sewage in 1985. as of august 2007, several large hotels and businesses have stated their intention to stop using phosphate detergents, in an effort to preserve the quality of the lake water.