| Lock Name: | Molesey Lock |
| Waterway: | River Thames |
| County: | Surrey |
| Operation: | Hydraulic |
| Length: | 81.78m (268.31feet) [1] |
| Width: | 7.56m (24.8feet) |
| Fall: | 1.85m (06.07feet) |
| Maint: | Environment Agency |
| First: | 1815 |
| Latest: | 1906 |
| Sealevel: | 20feet |
| Enda: | Teddington Lock |
| Distenda: | 4.8 miles |
| Extra: | Power is available out of hours |
Molesey Lock is a lock on the River Thames in England at East Molesey, Surrey on the right bank.
The lock was built by the City of London Corporation in 1815 and was rebuilt by the Thames Conservancy in 1906. It is the second longest on the river at 81.78m (268.31feet); it is the second lowest of the non-tidal river and third-lowest including Richmond Lock on the Tideway. Upstream of the lock are moorings for small boats, specifically skiff, paddleboard, small speedboat and open kayak hire, a tour boat pier, a kiosk and van parking space for ice cream and soft drinks. A few metres upstream is a combined side weir and front weir followed by an attached ait, Ash Island. A low backwater against the opposite bank which forms the waterside to homes sometimes called the Hampton Riviera continues to a small upper weir.
Molesey Lock is within sight of the walls of Hampton Court Palace in southwest London on the opposite bank through the arches of Hampton Court Bridge, designed by Edwin Lutyens (220 m away).
The lock's proximity to Hampton Court and boat hire at the site made it a popular venue for spectators in the Victorian and Edwardian eras, the tree-lined lock attracts large numbers of visitors for nine months of the year. Hire boat companies and ice cream sales attract visitors in all months apart from winter.
A lock was first proposed in 1802 because of then-shallows upstream at "Kenton Hedge and Sundbury Flatts above" - nothing came of the suggestion. In 1809 the proposal was resubmitted Parliament passed the Act for construction of the lock in 1812. Building began in 1814 and it opened in 1815 with an Italianate lockhouse. The first lock keeper was killed in a horse race at Moulsey Hurst and his successor discharged after incidents of stealing from barges. In 1853 changes were made to the lock in anticipation of lower water levels caused by the extraction of water upstream. Fish ladders were added to the weir in 1864 and the boat slide built in 1871. Such was the popularity of boating that in 1877 the navigation commission stationed a boat and crew in busy days above the weir in case of accidents. The lock was rebuilt in 1906.[2] On the small lock island is a plaque commemorating Michael J Bulleid whose work for salmon conservancy allows them to scale the river.
The lock is upstream of Hampton Court Bridge on the right bank, which is here the south side. It is immediately accessible from Hurst Road/Riverbank (A3050) with pavements and a sloped approach and is from the platform at Hampton Court railway station terminus on the same bank.
After the lock cut is Tagg's Island which provides mooring for houseboats some of which are three storeys high. On the Surrey bank here is the "Eights Tree" a tall metal sculpture outside Molesey Boat Club. The left bank here is sometimes marked as the Hampton Riviera featuring the Swiss Cottage, the Astoria Houseboat and an array of period buildings at Hampton such as Rotary Court. Garrick's Ait similar in size to Ash Island, is residential, by the Hampton-Molesey Hurst Ferry, which runs in the summer between Hampton and Moulsey Hurst park on the right bank.
There are reservoirs on both sides of the river above Sunbury Lock, created after the 1852 Metropolis Water Act[3] made it illegal to take drinking water for London from the tidal Thames below Teddington Lock because of the amount of sewage in the river. The Hampton Waterworks were built on the northern bank in the 1850s by three companies — the Grand Junction Waterworks Company, the Southwark and Vauxhall Waterworks Company, and the West Middlesex Waterworks Company. The reservoirs at Molesey on the southern bank were established in 1872, by the Lambeth Waterworks Company, followed three years later by the Chelsea Waterworks Company. Both companies had previously built their reservoirs at Seething Wells below Molesey Lock, but the turbulence caused by the River Mole, River Ember and The Rythe meant there was too much mud brought in with the water.[4]
The Thames Path stays on the Surrey bank (right bank) to Sunbury Lock. The next bridge is half-way along the long reach upstream, Walton Bridge. A large tank trap from World War II is visible beside the right-bank reservoirs.