The River Lea originates near Luton and, for much of its course towards the Thames, meanders through the Hertfordshire countryside as a modest waterway[cite: 1]. Upon reaching Hertford, it transitions into the Lee Navigation[cite: 1]. Before 1770, the original navigable River Lea — known as the ‘Barge River’— experienced significant alterations due to the creation of flood relief channels and large reservoirs, resulting in the loss of approximately 80% of its original path[cite: 1].
The River Lea is now regarded as one of the UK’s most heavily engineered waterways[cite: 1]. In many areas, the river has become a shallow channel lined with concrete, largely devoid of wildlife and flora[cite: 1]. Recent efforts have been made to restore ecological balance by constructing new channels, including one south of Fielde’s Weir and another from Holyfield Weir past Cheshunt and Waltham Abbey[cite: 1].
The Lee Navigation, a purpose-built route, is considered the more attractive watercourse through the Lower Lea Valley southwards from Enfield, consisting primarily of canal sections[cite: 1]. Historically, it intersected with several parts of the River Lea, although most of these connections have since disappeared[cite: 1]. The loss of routes such as the passage into central Waltham Abbey and various secondary river channels — which formerly provided additional miles of navigation — is widely seen as regrettable and indicative of the extensive modifications made to the natural waterways of the Lea Valley[cite: 1].
On a more positive note, the Lee and Stort Navigations are unique within the national system for offering passage into Essex, with significant stretches of the Lee Navigation falling within Essex (most are navigable segments of the River Lea)[cite: 1]. Another notable aspect is that the navigation enables vessels to cross Earth’s western hemisphere, while the Stort Navigation is entirely situated in the eastern hemisphere[cite: 1]. Comparatively, the only other UK waterways crossing the Greenwich meridian are the eastern reaches of the River Witham and Witham Navigable Drains[cite: 1].
This feature examines the Lee Navigation (and remaining sections of the River Lea incorporated into the navigation) between Bow Locks and Hertford, covering approximately 26 miles (28 miles from Limehouse)[cite: 1]. A map at Bow Locks marks the beginning of the Lee Navigation[cite: 1]. The River Lea enters the Thames at Lea Mouth, near Canning Town, opposite the Millennium Dome[cite: 1]. The initial segment, known as Bow Creek, is a highly tidal section rarely used for navigation, overseen by the Port of London Authority, with British Waterways’ jurisdiction commencing just south of Bow Locks[cite: 1].
Originally, the Lee Navigation began at Bow Locks, as the tidal River Lea served as the sole southern access point before the opening of the Limehouse Cut in 1770[cite: 1]. There are four entry points to the Lee Navigation: via the Limehouse Cut, Bow Locks, Three Mills/City Mills Locks, or the Hertford Union Canal, which enters the old Hackney Navigation Canal section above Old Ford Locks[cite: 1].