Teddington Lock

Teddington Lock, located between Ham and Teddington, is a complex structure consisting of three locks and a weir. Initially built in 1810, the lock marks the historic boundary between the Port of London Authority, which oversees navigation downstream to the North Sea, and the Environment Agency, responsible for the river upstream. An obelisk on the Surrey bank signals this boundary. Teddington Weir, part of this complex, is notable for marking the usual tidal limit of the Thames. The lock itself is the lowest full-tide lock on the river and the second lowest of all-tide locks. This is the point where the freshwater of the Thames meets the tidal water from the North Sea.

Teddington Lock comprises a large weir and three locks: a conventional launch lock for regular use, a substantial barge lock, and a small skiff lock. The barge lock, designed to accommodate long barges, steamers, and passenger ferries, has an additional set of gates halfway along its length, allowing it to operate more efficiently with shorter vessels. The lock complex is built around two narrow, reinforced islands. The upper island is accessible via the lock gates or the Teddington Lock Footbridge.

The larger lock sits on the river's southern, or Surrey, bank, which runs northeast. The middle lock, most frequently used, spans a thin island with lawns, seating areas for boat owners, a lock keeper's cabin, and a narrow strip of concrete that includes a canoe and kayak portage facility. Downstream of the lock is the Richmond and Twickenham stretch of the Thames, a semi-tidal reach made navigable at low tide by the Richmond Lock and half-tide barrages.

The first lock at Teddington was built in 1810, following an Act of Parliament that authorized the construction of several locks and weirs between Staines and Teddington. The lock was completed in 1811, although the weir took longer to finish due to delays caused by flooding. The original lock, located further upstream than the present complex, was met with resistance from local fishermen and bargemen, leading to the lock keeper being armed for protection.

Over the years, the lock underwent several repairs and reconstructions. In 1829, the weir was destroyed by ice, and in 1857, the current lock was built at its present location, along with the addition of a narrow skiff lock. The barge lock, the largest on the river, was constructed between 1904 and 1905.

The footbridges at Teddington Lock, which connect the locks and the weir pool, were opened in 1889 and are now Grade II listed structures. During World War II, Teddington Lock served as an assembly point for a large flotilla of small ships used in the evacuation of Dunkirk.

In the early 21st century, renovation and improvement work was carried out around Teddington Lock as part of the Thames Landscape Strategy Teddington Gateway project. In 2009, a local community group initiated a feasibility study to harness electricity from Teddington Weir, inspired by similar projects like Torrs Hydro and Settle Hydro. The proposed Ham Hydro project aims to use three reverse-Archimedean screws to generate 492 kilowatts of electricity. Environmental concerns have delayed the project, and further surveys are pending.

The lock can also be reached via footbridges from Ferry Road in Teddington. Upstream from the lock are Trowlock Island and Steven's Eyot.

The riverbanks near the lock are often referred to by their historic names: the Middlesex Bank (Teddington side) and the Surrey Bank (Ham and Kingston side). The Middlesex side features homes, communal grounds, and recreational clubs. In contrast, the Surrey side has a green buffer and towpath, widening into Canbury Gardens before reaching the town centre of Kingston.

The reach between Kingston Bridge and Hampton Court is home to several sailing and rowing clubs, skiffing and punting clubs, the Royal Canoe Club, and Sea Cadet centres. The Thames Path follows the Surrey side of the river to Kingston Bridge, crosses over to Hampton Court Park, and then returns to the Surrey side at Hampton Court Bridge.

Numerous pleasure boats operate along this stretch of the river, offering services between Kingston and Hampton Court, making it a popular area for recreational boating and riverside activities.