 Where Avon Water and Yaldhurst stream have flooded, fine silt and clay has deposited in the vicinity of the river banks forming floodplain alluvium.Pennington sits on a broadly flat plateau with shallow inclined gullies which are the natural water courses draining to Avon Water to the west and Yaldhurst stream to the east.St Marks Church is approximately 24m above sea level, whilst Gordleton Business Park is approximately 28m above sea level.