Event/Activity EPM220 - North Portsea Island Coastal Flood And Erosion Risk Management Scheme - Phase 3: An Archaeological Watching Brief

An archaeological watching brief was carried by Pre-Construct Archaeology during ground work for geotechnical work associated with the North Portsea Island Coastal Flood and Erosion Risk Management Scheme. The watching brief took place between the 19st April and 11th May 2016. A total of 18 Window Samples, 17 Boreholes and 18 hand-dug trial pits were monitored on three separate frontages. Frontage 1 followed the east frontage of Tipner Lake from Tipner to the M27/A3 junction. Frontage 2, Ports Creek, ran from the M27/A3 junction to the railway line. Frontage 3 ran from Anchorage Park to Milton Common. A section of the frontage between Frontages 2 and 3, known as Frontage 2b, was monitored by Wessex Archaeology in 2014. Frontage 1 A total of seven window samples, six boreholes and six trial pits were monitored. Two general sequences of deposits were observed, one on the foreshore and a second behind the foreshore. The sequence of deposits in boreholes behind the foreshore revealed a highly disturbed topsoil/subsoil (probably representing made-ground) to a depth of 0.2m-1.1m, which contained modern clear glass, CBM (ceramic building material), white and blue ceramic, slate and mortar. Below this was a layer of orange clay with signs of disturbance at the top. One borehole contained evidence of oyster shell and other shells. Frontage 2 A total of four window samples, four boreholes and five trial pits were monitored. A general sequence of deposits was identified. Evidence of modern CBM was observed within the topsoil of borehole starter pits and a trial pit opened above the water table within Hilsea Lines. Evidence of wooden posts observed in two trial pits and a core sample were thought to relate to the construction of the modern sea wall. Frontage 3 A total of seven window samples, seven boreholes and seven trial pits were monitored. A general, but less consistent, sequence of deposits was identified. Modern CBM, pottery and animal bone (thought to be tidal detritus) was observed within the vicinity of one window sample and one trial pit. CBM, glass and blue and white china were observed in a deposit of disturbed subsoil revealed in a borehole behind the sea wall. Another deposit of made ground in this area contained modern glass, CBM, pottery and clinker. A deposit of highly disturbed sub-soil/made ground beneath the footpath in this area contained CBM, pottery and glass 'clinker'. No significant archaeological deposits, features or finds were identified or recorded during the watching brief. Due to the limited nature of the investigations it is not possible to conclude with certainty whether the areas investigated may or may not retain archaeological potential. However, the deposits that were revealed appear to represent a fairly consistent sequence of foreshore deposits or made ground overlying natural deposits of clay and/or chalk. None of the 19th and 20th century material recovered during the watching brief was of archaeological significance, and as such was not retained. N.B. The points on the HER GIS event layer for this record represent the approximate positions of window samples, boreholes and trial pits. These points have been estimated using a map contained in the site report, and the site archive should be consulted to obtain the exact positions. Museum Accession No: 2017/55