"The Binn Wall", Completion Ceremony - 16 September 1998
Completion of the Binn Wall Defences 16 September 1998
Main Statistics and Facts
Length of Defence: 1310 metres
Total Overall Cost £ 6.1 million
Start Date April 1993
Completion Date August 1998
Rock Armour Quantity 76,000 cubic metres
Contractors
Contract 1 Laing-GTM
Contract 2 Edmund Nuttall
Contract 3 Edmund Nuttall
Contract 4 Dew Construction
Designers Sir William Halcrow & Partners
History and Background
The original Binn Wall was constructed in 1815 to provide flood protection for the villages of Severn Beach and New Passage. The Wall has a long history of modifications and upgrading and has failed a number of times. The defence was prone to overtopping when high tides combine with high winds.
The Binn Wall forms a major part of the Avonmouth to Aust Cell. These defences protect an area of 35 sq km between the old Severn Bridge and Avonmouth including 920 residential properties and considerable industrial development, farm land, roads and railway lines.
The total cost of the schemes in the Avonmouth to Aust Cell, including the Binn Wall, amount to £9.9 million. The cost benefit ratio for the cell is 10:1.
Completion of the Binn Wall also marks the completion of the programmed works in the Avonmouth to Aust Cell.
The Severn Estuary adjacent to the Binn Wall is a Site of Special Scientific Interest and of international importance for wildfowl and waders. Efforts have been made to reduce the impact on the SSSI and the a monitoring programme has been agreed with English Nature to monitor the effects of the scheme. This programme started in 1994 and will run to 2003 and so far has shown that there are no adverse effects.
The Binn Wall Scheme
The new defence gives protection against a 1 in 100 year flood event. The scheme consists of a rock armour berm generally 13 m wide, a concrete access road, a sloping revetment and a one metre high wave return wall. The sloping revetment has been faced using stone from the original Binn Wall.
The scheme was grant aided at 35% of the works cost by the Ministry of Agriculture, Fisheries and Food. The scheme was project managed by the Agency's Regional Engineering Services Department and it will be maintained by the Lower Severn Area Office.
The work was split into 4 contracts. Contract 1 was for works immediately below the Second Severn Crossing which had to be complete before the bridge was constructed. Contracts 2 & 3 were for the sections nearest to Severn Beach and New Passage. Contract 4 was the most recent section to be constructed and covers the area occupied by the bridge contractor for his access and compound until recently.
A landscape mitigation scheme has been carried out at the west end of the Binn Wall.
The Severn Way long distance footpath runs through the scheme. This is jointly promoted by the Environment Agency and local authorities.
A Section Through the Binn Wall
The Binn Wall
The Binn Wall at Spring High Tide
[Source:Environment Agency
