Starting in the twelfth century, works were carried out to drain Stratford Marshes and several of the waterways were constructed to power watermills.

Improvements to the channels which form a central feature of the Olympic Park included the largest aquatic planting scheme ever carried out in Britain.

[9] The Bow Back Rivers cross an area originally known as Stratford Marsh, an area of common Lammas land, where inhabitants had common rights to graze horses and cattle between Lammas Day (1 August) and Lady Day (25 March), but which was used for growing hay for the rest of the year.

[12] Dates for the earliest use of the rivers by boats are unknown, although a late Bronze Age dugout canoe and parts of a Saxon barge have been found in the marshes at Walthamstow.

The first alteration to the natural river may have been made by Alfred the Great, who cut another channel to strand a force of Danes in 896, according to the Anglo-Saxon Chronicle.

The Abbey continued the process of draining Stratford marsh begun in the Middle Ages and creating artificial channels to drive water and tide mills.

1. c. 18), empowered the Lord Mayor of London to make improvements to the river to ensure that supplies of grain continued to reach the capital.

These works included a new cut near the Thames, probably the section of river between Bow Tidal Gates and Old Ford, on which no tolls were to be charged, and a pound lock was constructed at Waltham Abbey, only the second to be built in England.

[4] Crossing the Back Rivers by a series of low-level bridges is the Northern Outfall Sewer which leads to the Abbey Mills Pumping Station, both of which were designed by Joseph Bazalgette in the 1860s.

[4] The East London Waterworks Company was set up in 1807, and built works at Old Ford, where they extracted water from the river.

The supply to the works was moved further upstream in 1829, and in 1830 they built a canal, running parallel to the Hackney Cut, so that water could be obtained from Lea Bridge.

[20] Where there had been a reservoir to the south of the Middlesex Filter Beds weir in 1850,[21] maps from 1870 show the site occupied by a waterworks, and the canal which supplied the Old Ford works running beside the Hackney Cut.

The water supply canal passed under the old river to feed two compensation reservoirs to the north of the Great Eastern Railway tracks.

[23] Twenty years later, the northern Waterworks River rejoined the Lee at Bully Fence, and the section between there and Carpenters Road had been filled in.

Although the River Lee was navigable up to Hertford, this had been achieved by the use of flash locks, where a single gate created a channel through a weir.

[26][27] The Limehouse Cut would give direct access to the River Thames, avoiding the tidal Bow Creek.

It closed again briefly in December, when a bridge collapsed into it, and it was soon decided that it was too narrow, and so was widened to allow barges to pass each other along its complete length.

[4] In the 1860s, the income from the navigation had dropped, as a result of attempts to compete against the railways, but economies were made, and capital works continued.

Marshgate Lock was situated to the west of the junction between the Pudding Mill River and Saint Thomas Creek.

The reconstructed lock was built on the site of the City Mill Pool, and had two sets of gates at its eastern end, to prevent high tidal levels in Waterworks River flooding the waterways to the west.

[36] In 2005, the lock was partially restored as part of the planning gain required from the developers of the adjacent Bellamy Homes housing scheme.

The channel included sluices to regulate water levels above it, but these became redundant once the tide mills ceased to operate, and eventually seized up.

[41] The Bow Back Rivers fell into this category, and remained neglected until their full restoration was enshrined in a British Waterways policy document in 2002.

The lock was built to allow construction materials to be delivered to the site and spoil to be removed,[38] and the final cost was £23 million, which included a sluice on the Three Mills Wall River.

[38] The Olympic Delivery Authority took the decision to culvert more of the Channelsea River, where it crossed the northern part of the site.

It remains a designated main river, and so they had to liaise with the Environment Agency on matters of flood-risk management, and a site was identified which would provide compensation for the loss of habitat caused by the culverting.

Much of the old River Lea was inaccessible to the public prior to the project, but is a central feature of the northern parklands that have been created.

The Heritage Lottery Fund provided £680,000 towards the cost of the project, with other grants coming from the London Legacy Development Corporation and the Inland Waterways Association.

As well as acting as a lock, the radial gates allow water to be distributed around the Bow Back Rivers for flood prevention purposes.

The gates were due to be tested during the summer months, with a formal opening scheduled for the East London Waterways Festival in August.