Dartford Cable Tunnel

The Dartford Cable Tunnel is a 2.4 km utility tunnel beneath the Thames, upstream of the Dartford Crossing. With a diameter of ~3 m (10 ft), it carries a 400 kV National Grid electrical transmission cable. It is accessible by foot as a crossing of the Thames, but by authorised personnel only.^[1][2][3] It was built in 2003–04 at a cost of £11 million (equivalent to £22 million in 2023).^[4] The tunnel plays a crucial role in maintaining electrical supply infrastructure beneath the Thames, ensuring reliable power transmission.^{[citation needed]}

Dartford Cable Tunnel
Location
Country	UK
Coordinates	51°28′5″N 0°14′58″E
Ownership information
Owner	National Grid plc
Construction information
Commissioned	2004
Technical information
Type	Underground tunnel
Type of current	AC
AC voltage	400 kV

See also

• 400 kV Thames Crossing
• Thames Cable Tunnel
• Utility vault
• Crossings of the River Thames
• Tunnels underneath the River Thames