Cambridge Rowing Lake Milton Landbeach and Waterbeach Cambridgeshire Archaeological Investigation Report o a Oxford Archaeology March 2003 Client:client logoCambridge Rowing Trust Issue No: 1 OA Job No: 2004 NGR: TL 490 635 Oxford Archaeology Cambridge Rowing Lake Carl 03 Stage 1 Archaeological Mitigation Cambridge Rowing Trust Cambridge Rowing Lake Milton, Landbeach and Waterbeach Cambridgeshire STAGE 1 A RCHAEOLOGICAL MITIGATION CONTENTS 1. Introduction........................................................................................................................ 1 1.2. Geology and topography............................................................................................. 2 1.3. Archaeological background ........................................................................................ 2 2. Aims of the investigation ................................................................................................... 2 2.1. General aims ............................................................................................................... 2 2.2. Detailed aims .............................................................................................................. 3 3. Methodology ...................................................................................................................... 3 3.1. Scope of fieldwork...................................................................................................... 3 3.2. Fieldwork methods and recording............................................................................... 3 3.3. Finds............................................................................................................................ 4 3.4. Palaeo-environmental evidence .................................................................................. 4 3.5. Presentation of results................................................................................................. 5 4. Results................................................................................................................................ 5 4.1. Description of deposits ............................................................................................... 5 4.2. Finds.......................................................................................................................... 13 4.3. Palaeo-environmental remains.................................................................................. 14 5. Discussion and interpretation........................................................................................... 16 Appendix 1 Prehistoric pottery.............................................................................................. 19 Appendix 2 Later prehistoric and Roman pottery ................................................................. 19 Appendix 3 Worked flint....................................................................................................... 19 Appendix 4 Animal bone ...................................................................................................... 20 Appendix 5 Environmental data............................................................................................ 22 Appendix 6 References ......................................................................................................... 35 LIST OF FIGURES Fig. 1 Location of site Fig. 2 Trench location plan Fig. 3 Trench 1. Plan and section through ditches 111 and 116 Fig. 4 Trench 2. Plan and sections through palaeochannel 208 and tree throw holes 210 and 212 Fig. 5 Trench 3. Plan and sections through ditch 305, pits 307 and 312 and posthole 314 Fig. 6 Trench 4. Plan and sections through ditches 405, 407 and 410 and palaeochannel 414 Fig. 7 Trench 5. Plan and section through ditches 505, 507 and 510 Fig. 8 Trench 8. Plan and section through ditch 807 Fig. 9 Trench 10. Plan and section through ditch 1007 Fig. 10 Trench 17. Plan and sections through ditches 1708 and 1711 Fig, 11 Trench 18. Plan and sections through ditch 1805, pit 1809 and posthole 1811 Fig. 12 Trench 21. Plan and sections © Oxford Archaeological Unit Ltd. October 2001 i U:\CARL 03 Final Report.doc i Oxford Archaeology Cambridge Rowing Lake Carl 03 Stage 1 Archaeological Mitigation © Oxford Archaeological Unit Ltd. February 2004 U:\CARL 03 Final Report.doc 1 Oxford Archaeology Cambridge Rowing Lake Carl 03 Stage 1 Archaeological Mitigation SUMMARY During September and early October 2003 Oxford Archaeology carried out Stage 1 Mitigation at the southern end of the proposed international standard rowing course sited on land north of Cambridge. The work comprised twenty one trenches excavated in the floodplain of the River Cam, examining the line of the proposed Canal (from the River Cam to the Rowing Lake) and the Cut (forming the access channel to the main rowing course). In addition to the standard archaeological recording processes, detailed geo-archaeological recording of the alluvial sequence in each trench was carried out. A pit and a posthole, both containing pottery dated to the Bronze Age were discovered in Trench 18, on what would appear to be a raised gravel island toward the north end of the area under investigation. At the southern end, a middle Iron Age pit and two pits of Roman date were recorded in Trench 3, at the edge of the first gravel terrace, while Roman activity on the floodplain itself was represented by a small number of linear ditches. These features were probably created by communities living on the edge of the terrace, in order to drain the area for use as pasture, and to define trackways providing access to the river itself. Preliminary assessment of the palaeo-environmental indicators has indicated that the northern half of the area may have existed as a back- swamp, while the southern half was damp grassland or meadow. During or shortly after the Roman period fen conditions developed, resulting in the formation of a layer of peat across the entire area. There was no evidence for subsequent human occupation until the post-medieval period, when a series of boundary ditches were established near the river, along with some small-scale gravel quarrying. 1. INTRODUCTION 1.1.1. The Cambridge Rowing Trust proposes to construct an international competition standard rowing course 2000 m long north of Cambridge on land lying in the parishes of Milton, Waterbeach and Landbeach (NGR TL 490635, centred) (Fig. 1). The development area lies adjacent to the River Cam in an area of high archaeological potential, including areas of former floodplain containing alluvial deposits likely to include significant palaeo-environmental evidence. Oxford Archaeology (OA) has proposed a detailed programme of archaeological investigation in advance of the development, presented in the Research Design for the Archaeological Mitigation of the Cambridge Rowing Lake in the Parishes of Milton, Landbeach and Waterbeach (OA 2003, hereafter ‘ Research Design ’). The current report presents the results of an archaeological investigation carried out by OA in September 2003, designated in the Research Design as Stage 1 Mitigation. 1.1.2. The Stage 1 Mitigation consists of a programme of work designed to provide additional information about and characterisation of particular areas of the development area and to inform further refinement of the overall mitigation strategy. In particular, the work examined the line of ‘The Canal’ and ‘The Cut’, two components of the southern half of the Rowing Lake. © Oxford Archaeological Unit Ltd. February 2004 U:\CARL 03 Final Report.doc 1 Oxford Archaeology Cambridge Rowing Lake Carl 03 Stage 1 Archaeological Mitigation 1.1.3. The Cut is to consist of a linear channel 40 m wide and 1000 m long aligned SSW- NNE, approximately parallel to the course of the River Cam. The excavation of trenches around the channel to accommodate the clay seal to be inserted around all the water features of the Rowing Lake will result in a total impact some 50-55 m wide. The Canal will be constructed in the same way as The Cut but its channel will be only 20 m wide, giving a maximum impact width of 35 m over its length of 180 m. Both channels will be c 2 m deep. 1.2. Geology and topography 1.2.1. The site lies to the west of the River Cam, on the first gravel terrace. The topography is generally flat, lying between 3 m and 7 m OD. The geology consists of Gault clay overlain by Pleistocene river gravel, which in places is blanketed by Pleistocene and later alluvial deposits. 1.3. Archaeological background 1.3.1. The archaeological background to the project has been presented in the Research Design , from which the following summary is drawn. 1.3.2. Terrace-edge locations have been favoured for settlement in all periods, since they provide easy access to the river and its associated resources while being safe from the danger of flooding. A revue of previous archaeological investigations in the vicinity, combined with desk-based survey of the existing documentary and aerial photographic evidence and the results of a programme of field-walking, test-pitting and evaluation trenching carried out in 1995 by Cambridge County Council Archaeological Field Unit (Robinson and Guttmann 1996) has identified a number of areas of occupation within the development area, dating primarily from the Iron Age to Anglo-Saxon periods. This settlement predominantly extends in a band along the edge of the second terrace, running NE-SW, obliquely across the northern half of the development