NHER 27280 (Monument record) - Possible former medieval clay and peat extraction

March 2005. Norfolk NMP.
An area of possible former medieval clay and possibly peat extraction has been identified on aerial photographs within the marshes at Heigham Holmes, Potter Heigham (S1-2). The site is centred on TG 4466 2085 and consists of a concentration of possible former cuttings visible as amorphous shaped darker, wetter and slightly sunken areas on the photographs. Many of these appear to be linked by channels. These possible cuttings vary in size from 200m across to as narrow as 20m. Although it is possible that these wetter areas are the remains of natural pools on ground liable to flood, other areas exhibiting the same characteristics have proved, through historic map evidence, to be former Broads, such as at Eastfield Marsh (HER 35363) and Cotton’s Marsh (HER 32157). Other nearby Broads, such as Horsey (HER 13507) and Heigham Sounds (HER 8387), are thought to largely be the product of clay extraction (S4; p 87), although some peat existed within the deposits (S5; p45).

In 1945-6 areas of standing water are visible within the larger spreads, such as at TG 4420 2105 and TG 4488 2095 (S1-2). These pools and extraction areas only tend to be visible on the earlier aerial photographs, in particular those taken in the 1940’s. The lack of visibility and shrinking of some of these features on the later aerial photographs is indicative of the continued silting and drainage of these cuttings (S3).

Extraction of surface peat and turf continued throughout the post-medieval also and a group of similar extraction features to the immediate south (NHER 43700) are thought to be post-medieval. However these pits at Heigham Holmes appear to be cut through by a series of late medieval to post-medieval drainage dykes and boundaries (HER 27281), indicating that the extraction must pre-date these boundaries.
S. Massey (NMP), 29 March 2005.