Yorkshire Water estimates (based on United Kingdom Water Industry Research Limited, Greenhouse Gas workbook) that designation will increase carbon dioxide equivalents by 380 kilotonnes during construction and 125 kilotonnes per year through operations.
Severn Trent Water estimates an increase of between 100 and 150 kilotonnes of carbon dioxide per year, a 20 to 30 per cent. increase on current emissions. Additional emissions from Anglian Water will be much smaller.
If the UK was required to designate the Humber as sensitive to eutrophication, industry has estimated the capital cost of additional treatment to be approximately £900 million, with operating costs of approximately £50 million a year.