Fears for water quality in Wye and Severn as chicken farming numbers hit 51m

More than 51 million chickens are being industrially farmed in the river valleys of the Severn and Wye - equal to 79 chickens for every person in the region, according to new figures.

- Sandra Laville

The exponential rise in large intensive poultry units (IPUs) in the valleys is a key driver of river pollution. Chicken droppings contain more phosphates - which starve fish and river plants of oxygen - than any other animal manure.

The figures can be revealed by the Guardian as campaigners bring a judicial review case to try to stop the development of another IPU that has been granted planning permission in Shropshire. The proposed unit would house nearly 250,000 chickens.

The Wye and Severn rivers run partly through the Shropshire, Herefordshire and Powys local authority areas. None of the three councils keep data on the number of IPUs that have been granted planning permission.