Construction of the M5 Motorway over recent soft clays within the Somerset Levels left behind a legacy of geotechnical information which has been assembled on a computer file containing the findings of 243 borings between Clevedon and Huntsworth. The paper gives examples of the use of the file for production of representative profiles of moisture content, strength, Atterberg limits and compression behaviour. These serve to highlight many of the now familiar characteristics of Somerset Alluvium and similarities with other recent deposits in the U.K. In particular they indicate the variability to be anticipated due to changes in consistency of the material, its sensitivity and some reflection on the method of sampling and testing. The profile of over-consolidation within the zone of desiccation is also clearly seen.
Some tentative correlations are made between Atterberg limits and corresponding measurements of sensitivity, strength and compression constants (Cc, λ) on the basis of Critical State theory, which serve to show a more consistent and more useful pattern.