Awre once claimed some lands in the parish of Slimbridge across the river. In the mid-13th century, the main river channel that runs down the estuary switched its course and began to erode the shore, riverbank and land on the Awre side. As a result, it is estimated that Awre lost about one third of its territory and even today, the parish boundary is set about three quarters of the way across the estuary as if the parish is hoping that one day, its lands will be restored.