Second Severn (M4) Crossing
The bridge is a cable - stayed bridge with a total length of 912 metres across the main navigation channel of the River. The main span of the bridge is 456 metres long and gives a clearance of more than 37 metres above the highest tide level. The viaducts connecting the bridge to both the Gwent and South Gloucestershire shores are 2,150 and 1,850 metres long. The whole crossing is designed with 3 metre high wind shielding (the first Severn Bridge has had to be closed for lorries in high winds and this should help to solve the problem). The bridge has three traffic lanes, and a hard shoulder in each direction, but no footway/cycleway provision.
View of the M4 bridge from upstream on the south shore
Blue lines indicate the cable stays
View from a car crossing the bridge
View under the bridge from the south shore