Waterworks River

From the Wikipedia page

Waterworks River is a tidal river in the London Borough of Newham, one of the Bow Back Rivers that flow into the Bow Creek part of the River Lea, which in turn flows into the River Thames.

The river is an artificial channel, cut for the East London Waterworks Company in 1743, from the Old River Lee channel (above Old Ford Lock), to supply a reservoir at Saynes Mill, Stratford. It was widened to 100 feet (30.5 m) in the 1930s, as part of a project to prevent flooding in Stratford. The channel is lined with concrete slabs.

The river forms the border between the Aquatics Centre and Water Polo Arena on one bank, and the Olympic Stadium on the other.