River Lee Navigation

The Lee Navigation is a canalised river incorporating the River Lea (also [incorrectly] called the River Lee). It runs from Hertford Castle Weir to the River Thames at Bow Creek; its first lock is Hertford Lock and its last Bow Locks.

The Lee Navigation is named by Acts of Parliament and is so marked on Ordnance Survey maps. Constructed elements and human features are spelled Lee, such as the canal system and Lee Valley Park. The un-canalized river is spelled Lea, along with other natural features such as Lower Lea Valley.

The River Lea is a major tributary of the River Thames. It has a long association with navigation, as the marshes of Walthamstow have produced a dugout canoe from the Bronze Age and parts of a Saxon barge. According to the Anglo-Saxon Chronicle, the river was used by Viking raiders, and King Alfred changed the level of the river to strand Guthrum and his fleet. In more peaceful times, it became important for the transport of grain from Hertfordshire, but navigation of its southern-most tidal reaches of Bow Creek were difficult due to its tortuous meanders.

There is documentary evidence that the river was altered by the Abbot of Waltham to improve navigation in 1190, and in 1221, a pipe was laid across the river, which had to be protected from "the oars or poles of the watermen." The first Act of Parliament for improvement of the river was granted in 1425, this also being the first Act granted for navigational improvement in England. A second Act was passed in 1430, and both authorised local landowners to act as commissioners, who could make improvements to the river including scouring or dredging, and could recoup the cost of the work by levying tolls.

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