Emmanuel’s Common – uncovering a ‘lost’ chalk-stream channel and recreating a new reach of ‘reference reach’ chalk stream

• 350 meters – uncovering and restoring a natural, reference-reach chalk-stream channel abandoned my the mill-leat several centuries before (blue line in image)

• 250 meters – constructing a linking section of new ‘reference reach’ chalk stream to join the original channel to the existing channel (red line in image)

On an uncultivated reach of the River Nar near Castle Acre we discovered via satellite images a natural, unmodified reach of meandering chalk stream channel, cut-off and abandoned but never filled in (except for the upper 50 meters), several centuries ago when the river was straightened to create a mill-leat.

This was an opportunity to restore an incredibly rare reference reach of chalk stream channel, in parts completely unmodified by dredging or any other channel works. The stream held groundwater, but little flow, and was almost completely hidden until you walked into it through a very dense thicket of wet woodland and reedy meadow.

To link the recovered channel with the existing channel (prior to future works on the existing channel in Phase 2) we excavated a 250 meter section of recreated reference channel based on the cross-sections of the recovered channel upstream.

Delivered by the Norfolk Rivers Trust and Internal Drainage Board. Designed by Helen Mandley (NRT) and Charles Rangeley-Wilson