Letter: Salt water and tears

Sir: While I am intrigued by the possible transformation of insular Lincolnshire with Lincoln as an isthmus town, I was dismayed to read your account of the Agriculture Select Committee's report and the wildlife lobby's welcome for its "Let the coastline flood" policy (6 August).

With respect to the massive potential body of inland water between Nottinghamshire, Doncaster and the Humber, the outcome of a "do nothing" policy is likely to be a mess rather than a wilderness. If the sea is allowed to invade, not only will several hundred kilometres of new coastline be created and commensurate coastal defences be required, but the area could become a saltwater sump as urban, agricultural and industrial pollutants from the region's major rivers accumulate behind the tidal ebb and flow of the Humber.

Constructing a barrage across the Humber might protect existing habitats, enabling the creation of a non-tidal freshwater "lake", rather than a brackish "sound", alongside the usual benefits of energy generation and transport. But, to enjoy such choices, zero tolerance of water pollution from all sources, in particular agricultural chemicals, would be essential.

JOHN CLARK

Berlin