Soils to the eastern part of the area are slowly permeable clayey and fine silty soils. They are found on Carboniferous clay and shales typical of the Supra-Pennant Measures.
The eastern portion of the area features soils that are slow to drain, consisting of clayey and fine silty soil types. These soils originate from Carboniferous clay and shale found in the Supra-Pennant Measures geological formation.