Northam Bridge

Northam Bridge
Aerial view of the bridge in 2016
Coordinates	50°54′54″N 1°23′10″W / 50.915°N 1.386°W / 50.915; -1.386Coordinates: 50°54′54″N 1°23′10″W / 50.915°N 1.386°W / 50.915; -1.386
Carries	4 lanes (road)
Crosses	River Itchen
Locale	Northam, Bitterne Manor (both in Southampton)
Maintained by	Southampton City Council
Preceded by	St Denys Railway Bridge
Followed by	Itchen Bridge
Characteristics
Total length	148 metres (485 ft 7 in)
Width	13.5 metres (44 ft 3 in)
Longest span	32 metres (105 ft 0 in)
No. of spans	5
Piers in water	4
Clearance above	open-air
Clearance below	9.2 meters (30 ft 2.2 in)
History
Construction begin	1796 (original); 1954 (current)
Construction end	1799 (original); 1954 (current)
Opened	1799 (original); 1954 (current)
Northam Bridge Location in Southampton

The Northam Bridge is a road bridge across the River Itchen in Southampton, England, linking the suburbs of Northam and Bitterne Manor. The current bridge was the first major prestressed concrete road bridge to be built in the United Kingdom. The bridge carries the A3024 road as a dual carriageway, with two lanes on each carriageway.

Prior to the construction of the Northam Bridge, the southernmost bridge across the River Itchen was at Mansbridge. Mansbridge was the lowest crossing point of the river until the early 18th century, when the Itchen Ferry began operating between Woolston and St Mary's, downriver of Northam.

The Northam Bridge was the idea of David Lance, who acquired land in Bitterne and built Chessel House there in 1796. Realising that access to his land was poor, he encouraged the building of a bridge linking Bitterne Manor to Northam, together with roads from the bridge to Botley and a further bridge over the River Hamble in Bursledon (and onwards to Portsmouth), with the fork between the Bursledon and Botley roads passing close to Chessel House. The Northam Bridge Company was formed in 1796, funded mainly by Portsmouth businessmen.

The new route between Portsmouth and Southampton would be four miles (6 km) shorter than travelling via Mansbridge, and as a result the proposal to improve transport between the two important port cities was keenly supported by the Admiralty, especially since this was the time of the Napoleonic Wars. Consequently, when the Northam Bridge Company sought an Act of Parliament to build a bridge, the Act was passed quickly.