Bow Locks (No20) is a set of bi-directional locks in the London Borough of Tower Hamlets. The locks link the tidal Bow Creek to the River Lee Navigation, which is a canalised river. These locks were first built in 1850 and then rebuilt in 1930, at the same time as the Prescott Channel was cut nearby. At high tide, the tide from Bow Creek formerly flowed through Bow Locks, to raise the level of the canals, such as the Limehouse Cut. In 2000, these locks were modified to keep the tide out, to reduce silting in the canal system.