Shortlands sewer flows from Walthamstow, parallel with Dagenham Brook. The channel was largely filled in when the Lea flood relief channel was built from 1950–60.
The sewer formed the traditional boundary between the inclosed marsh and lammas lands of Leyton Marsh.
In the 16th century, prior to the development of the Lea Bridge Road, a wooden causeway comprising 12 footbridges led from Blackbridge, crossing the Shortlands sewer west of Hemstall Green, and over the marsh to Lockbridge (the earlier incarnation of the Lea Bridge of today).
The sewer was known as Blackmarsh as it travelled through Walthamstow Marshes, possibly the origin of the 'Black path'.
There are two remaining features. A Shortlands Sewer Trash Screen can be seen between the Waterworks Nature Reserve and Golf Centre and the adjacent Railway line. A short section of channel remains on the southern part of Walthamstow Marsh, west of the Flood Relief Channel, below electricity pylons.