NHER 68893 (Monument record) - Remains of post-medieval sea banks

May 2021. Desk-based Assessment.
Assessment of potential impact of proposed development.
See report (S1) for further details.
P. Watkins (HES), 27 January 2025.

May and August 2021. Geophysical Survey.
Magnetometer survey of part of large proposed development area (F3).
The results of this survey were potentially impaired by the presence of 'green waste' across the entire site, which created a dense, continuous spread of magnetic disturbance that may have masked archaeologically-significant anomalies.
A single high magnitude discrete anomaly identified in the north-east corner of the site may indicate the presence of remains associated with medieval or earlier salt production. This anomaly is though some distance from any of the possible saltern mounds visible as earthworks on aerial imagery and is not necessarily archaeological in origin.
Two west-north-west to south-south-east aligned linear anomalies in the western half of the site correspond with two former channels shown on the Ordnance Survey First Edition Six-inch map (S2). These were the most extensive of a series of parallel features extending from an area of 'saltings' that were enclosed by post-medieval sea defences (NHER 27078). There was no evidence for surviving remains associated with these former banks, although it should be noted that associated earthworks can be clearly seen in visualised LiDAR data for the site (reproduced in the report on the subsequent trial trenching).
A number of sinuous linear trends in the north-east corner of the site potentially represent drainage channels and/or natural variations in the natural alluvial deposits. As at the sites to the north and east these responses are bounded to the west by a faint north-to-south aligned trend. This may represent a geological boundary such as a former shoreline but does not correspond with the line of any of the known former sea defences.
Information from draft report. Final version awaited.
P. Watkins (HES), 27 January 2025.

September-October 2023. Trial Trenching.
Evaluation of part of large proposed development site (Trenches 14-20).
The majority of the seven trenches were placed to coincide with the former post-medieval sea banks recorded at this location (NHER 27078). The sea bank running between TF 6262 2271 and TF 6217 2235 was shown to be associated with a light yellowish brown fine sand, the top of which lay immediately below the present topsoil. An exploratory sondage demonstrated that the bank material lay above a mid-brown alluvial silt and survived to a depth of c.0.60m. The eastern sea bank running between TF 6268 2264 and TF 6222 2216 was composed of a similar light yellowish-brown silt deposit. Several sherds from a post-medieval pot of late 18th to 19th-century date were recovered from this material. The uppermost part of this bank also lay directly beneath the topsoil.
The final two trenches were placed in the flat ground to the west of the sea banks, in the vicinity of the two straight linear anomalies identified by the geophysical survey. A sondage excavated in one of these trenches exposed a very dark grey silt deposit at a depth of 1.8m. A sample taken from this material was found to contain abundant charcoal, along with small amounts of burnt clay, ceramic building material and animal bone and much marine shell. This deposit was sealed by a sequence of alluvial silts.
Information from draft report. Final version awaited.
P. Watkins (HES), 27 January 2025.