This summer, ULAS carried out a small archaeological investigation of a large earthwork bank, part of a medieval/post-medieval fishpond, next to the ruins of Grace Dieu Priory in north-west Leicestershire. This was to try and explain why water is being lost from the pond so that the Friends of Grace Dieu Priory can implement repairs and re-flood the pond.
Grace Dieu was once an Augustinian nunnery founded between 1239 and 1242 by Roesia de Verdun. In 1377 there were 16 nuns and a hospital for 12 poor people. At the Dissolution in 1538 it was converted into a Tudor mansion by John Beaumont. Most of the buildings were pulled down by Sir Ambrose Phillips in 1696. Today, extensive ruins of the priory buildings still survive, managed by the Friends of Grace Dieu Priory Trust, along with extensive earthworks, ponds and a substantial section of boundary ditch and wall situated alongside the Grace Dieu brook running along the western side of the site.
The investigation entailed four trenches, totalling 40 square meters, being excavated into the earthwork, placed carefully to cause minimal damage to the scheduled monument and to answer specific questions about two suspected historic outfalls believed to discharge beyond the pond bank into ditches to the north.
Excavations identified a complex sequence of development inside the pond bank with a possible medieval core built up into the present earthwork in the post-medieval period. Inside the pond, a thin spread of 16th century refuse sealed a bed of freshwater mussels covering the pond lining, possibly the remains of medieval mussel beds, evidence that the nuns were cultivating the bivalves on site during the last decades of the priory’s existence; whilst a possible medieval building was tentatively identified buried beneath the north edge of the earthwork. Much of the bank was built of clay and recycled masonry suggesting it post-dated the priory, perhaps being built up and enlarged during the site’s use as a post-Dissolution mansion. Narrow stone walls found running along the top of the bank may be garden features associated with this phase of the site’s history.
Overall, the pond bank appeared largely intact and in good condition and water loss from the pond was apparently occurring beneath the bank, not through an old culvert as previously suspected, but by exploiting natural sand and gravel beds beneath the pond and weaknesses in the internal structure of the pond bank, notably the unbonded foundation of a wall which is now acting as a new spring.