The Lee was an important waterway from Saxon times. About 1190, the Abbot of Waltham was permitted to make a cut to improve the navigation. In 1424 and 1430, it became subject to the very first Acts for the navigational improvement of any river. More improvements were made in the eighteenth century, which furthered the development of industry along the route. The Lee also provided an important supply of water to London.
Richard Thomas has compiled a very informative website with very comprehensive information on the history of the Rivers Lee and Stort. See the History of the Lee and Stort website.
In the early 1930s, significant investment was injected into the Bow Backs to improve their ability to accommodate both floodwaters and navigation. At this time two new locks were constructed at City Mills and Carpenters Road. In addition the Prescott Channel was constructed with a sluice gate at its southern end to retain water. In the 1950s the Prescott Channel sluice was removed when the mills ceased working and retained water was no longer required. Commercial traffic ceased to use the Bow Backs after the Second World War, and they were largely left to silt up and deteriorate.
In November 2003, consultation plans were published for the potential site of an Olympic village and these were firmed up following the announcement in 2005 that the Olympics games were to be hosted in London in 2012. The new works include a new 1.5-mile linking canal, from the Lee Navigation to the City Mill River with one lock. British Waterways had already dredged a route through the rivers to make them available for cruising again, and there is substantial investment in the area including a new lock and water control structure on Prescott Channel. The new Prescott Lock restores the Bow Back Rivers to navigation, creating a green gateway for barges entering the Olympic Park and reviving water transport in the area for the first time in 50 years. The lock is part of a wider strategy to maximise the use of the rivers in the area for wildlife, navigation and people, creating a thriving waterway legacy. Work is also underway to restore the tidal mill on the City Mill river which is the largest tidal mill of its kind in the world.