Bassenthwaite Lake The Lake District Still Waters Partnership Sediment analysis in the lake has shown that the major changes in water quality within Bassenthwaite Lake have not been through land use changes through the ages, but have occurred only mid way through the last century Following a review of the quality of the 20 largest lakes in the Lake District in 2002 by the Lake District Still Waters Partnership it was revealed that Bassenthwaite Lake needed priority attention and this was the catalyst for the formation of the Bassenthwaite Lake Restoration Programme