Thames Estuary The new airport would be built on a man-made island in the estuary north of Minster-in-Sheppey There is also some discussion about the need for a Lower Thames Crossing in order to alleviate traffic congestion at Dartford. The Thames Estuary is the focal part of the 21st-century toponym, the "Thames Gateway", designated as one of the principal development areas in Southern England. The appellation Greater Thames Estuary applies to the coast and the low-lying lands bordering the estuary itself. These are characterised by the presence of mudflats, low-lying open beaches and salt marshes, namely the North Kent Marshes and the
Canvey Island to Bowers Gifford and joins the London-Southend A13 at Sadler's Farm Roundabout. The two lanes of the A130 are currently the island's primary access route with 25,000 vehicles using the road and bridge per day. The B1014 and Canvey Road Bridge (or Canvey Bridge) crosses Benfleet Creek to South Benfleet, and provides access to the c2c London (Fenchurch Street) to Shoeburyness line via Benfleet railway station. Canvey Road Bridge was built in 1973, and replaced the island's first bridge to the mainland, which dated from 1931. The Colvin Bridge – named after the Lord Lieutenant of Essex, Brigadier-General R.B. Colvin