M4, Severn Bridge Crossing, between England & Wales.
N 51° 34.456 W 002° 42.008
30U E 520780 N 5713731
Quick Description: The Second Severn Bridge, Severn Estuary Crossing, Carrying the M4 Motorway between England & Wales.
Location: South Wales, United Kingdom
Date Posted: 11/9/2011 8:32:13 AM
Waymark Code: WMD2BP
The Second Severn Crossing (Welsh: Ail Groesfan Hafren) is a bridge which carries the M4 motorway over the River Severn between England and Wales, inaugurated on 5 June 1996 by HRH The Prince of Wales to augment the traffic capacity of the original Severn Bridge built in 1966. The bridge marks the lower limit of the River Severn and the start of the Severn Estuary.
Its location is further to the south than the old bridge and being more in line with the landward sides of the M4 motorway, is a shorter journey when travelling between England and South Wales. The junctions at each end are designed for most traffic to use this crossing – to use the old Severn Bridge crossing one has to leave the M4 and join the M48 motorway either at Aust or near Magor. The new crossing carries more traffic than the Severn Bridge, which is still in use. It is wider than the Severn Bridge, having three lanes and hard shoulder each way, compared to the two lanes, cycle path and footpath of the original crossing. The path taken by the bridge is close to that of the Severn Tunnel which has carried the railway line beneath the river since 1886.
Overall length of Crossing Structure 5,128m
Length of Shoots Bridge 948m
Length of Main Span 456m
Navigation Clearance 37m
Length of Welsh approach Viaduct 2,077m
Length of English Approach Viaduct 2,103m
Height of Main Span Pylon Towers 137m
Number of Approach Spans - Welsh Side 24
Number of Approach Spans - English Side 25
Maximum height of Approach Piers 48m
Number of foundations in Caissons 37
Total volume of concrete required 320,000m cubic
Weight of reinforcing steal 30,000 tons
Total length of pre-stressing steel 150,000m
Number of Stay Cables In Shoots Bridge 240
Total number of Concrete Deck Units 2,434
Approximate number of men employed 1000
Construction Period 1992 to 1996
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