MMO2884 - Post-medieval drainage ditches on Sherdon (Monument)

An area of regular post-medieval drainage ditches is visible on aerial photographs as earthworks on Sherdon, Exmoor. They were most probably cut during the mid 19th Century as part of the Knight family's attempt at agricultural improvement in this area. Centred at approximately SS 7940 3593, the majority of the ditches run diagonally across both sides of a valley or small combe, arranged in a "herringbone" pattern, and directing water into the small stream. A larger channel curves down from the summit of Sherdon and Horsen Hill to connect with the stream at its source. Similar drainage systems can be seen in many areas within the former Royal Forest of Exmoor, but according to Orwin, most failed to provide adequate drainage for the land to be enclosed. Orwin also refers to the Knight's land agent, Robert Smith, who advocated the construction of so-called "sheep drains" on the boggy ground to provide grazing land for cattle and sheep. [1-3] An extensive drainage system lies to the northeast of Horsen Hill. The ditches run along the contours to drain into a larger channel which itself flows into a tributary stream of the River Barle. A curving ditch runs from southeast to northwest across the slope above the ditches and flows into the main drainage channel of the system. The upper section of this contour or head drain is silted up, mostly obscured by reeds, and is visible intermittently as a scarp 0.6 metres wide and 0.75 metres high. The lower section of this contour ditch survives as a reed filled hollow some 2 metres wide and 0.6 metres deep. The drainage ditches to the west are mostly silted up and obscured by reeds; where they can be seen the ditches are shallow channels 0.5 metres wide and less than 0.25 metres deep. The drainage ditches to the east are also mostly silted up and obscured by reeds, but the lowest drainage ditch which runs northeast to southwest along the contours is clearly visible and is 1 metre wide and up to 1 metre deep. Part of a tributary stream of the River Barle has been deepened to aid the efficacy of the network of drainage ditches which discharge into it. The channel is 110 metres long, 4 metres wide and some 2 metres deep with steep sides and intermittent banks of spoil on the sides. [4] This record was enhanced as part of the National Record of the Historic Environment to Exmoor National Park Historic Environment Record data transfer project. [5]