Length of roadway
2.13 miles
Total length of Tunnel including approaches and branch Tunnels
2.87 miles
Width of main Tunnel between kerbs
36 feet
Width of branch Tunnels between kerbs
19 feet
Internal diameter of main Tunnel
44 feet
External diameter of main Tunnel
46 feet 3 inches
Weight of rock, gravel and clay excavated
1,200,000 tons
Weight of explosives used
560,000 1bs
Weight of cast-iron used in lining Tunnel
82,000 tons
Weight of concrete used
270,000 tons
Total length of electric cable in Tunnel
583.5 miles
Average cover of rock over the top of the Tunnel under the River
20 feet
Total number of bolts in cast-iron lining is approximately
1 million
Total number of men employed directly on tunnel construction
1,700
.
