PALAEO-ENVIRONMENTAL STUDY AREA P10 HAMBLE RIVER, SOLENT REGION, SOUTH COAST UK

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1 Hamble River, Solent region, south coast UK PALAEO-ENVIRONMENTAL STUDY AREA P10 HAMBLE RIVER, SOLENT REGION, SOUTH COAST UK AN ASSESSMENT OF THE ARCHAEOLOGICAL AND PALAEO-ENVIRONMENTAL EVIDENCE FOR COASTAL CHANGE IN THE RIA INLET OF THE HAMBLE RIVER, SOLENT REGION, UK Plate P10 Historic timbers exposed on the foreshore jostle with needs for marina development at Bursledon Point, Hamble River, south coast. 1. LOCATION The river Hamble lies in the central southern coastal region of Britain, between the international trading ports of Southampton and Portsmouth. It enters the east bank of Southampton Water some 5km downstream from the city of Southampton. The river is navigable some 10km inland where its tidal limit ends at the village of Botley. The lower section of the river has been the focus for much human activity, being easily accessible to boat traffic. The limit of yacht and powerboat recreation is 4.5km up-stream from the mouth of the river. This is the spot where the A27 trunk road crosses the river at Bursledon. The low height of the road bridge has discouraged boat access to upper reaches of the river. Cconsequently, above the bridge, the tidal waterway provides a range of important marine habitats set amongst shingle banks, mudflats and salt marshes. This area is partially bordered by semi-natural ancient woodland. The large tidal range uncovers extensive areas of mudflats at low water. These are important habitats for waterfowl, waders and gulls. The local underlying geology of this area is a combination of Barton and Bracklesham Beds. This has produced a terrain of soft and fertile sands and clays. The geology has helped shape the course of the 1

2 Hamble River, Solent region, south coast UK river. This is particularly evident at Bursledon where an outcrop of hard Barton Sand has forced the river into a crescent shaped diversion. The Hamble has offered a modest route of passage into the Hampshire hinterland since the earliest days of water transport. Unlike the Itchen, however, this route does not serve a major centre of population. The inlets and creeks along lower stretches of the river provide sheltered moorings and anchorages which are very much preferable to the less hospitable coast on the western side of Southampton Water. The history of the river shows that vessels have regularly sought shelter here at least since medieval times. Nevertheless, the demand for the shipping of cargoes has never been great. 2. MODERN HUMAN GEOGRAPHY The estuary falls within the County of Hampshire which is responsible for the strategic planning policy of the coastline. Development control rests with Eastleigh District Council for the west bank of the river and with Fareham District Council for the east bank. The balance between human use and the natural environment of the river has been an uneasy one. The 19th century brought an increased demand for shipbuilding in the lower Hamble. The minor ports of Hamble, Saltash and Bursledon owe much of their development to this industry. The 20th Century saw a diminution of shipbuilding activity yet the prosperity of these settlements was restored by a sharp increase in the number of yachts and other pleasure boats whose activities have become centred upon Hamble and Saltash (Plate P10). The County Structure Plan resists further development on the banks of the river and it recognises the importance of Lincegrove and Hackett's Marshes which are areas which are statutorily protected as Sites of Special Scientific Interest. The upper Hamble is designated the 'Upper Hamble and Woods SSSI'. The lower Hamble contains part of the 'Hook with Warsash Nature Reserve'. One particular element of the historic environment of the river has statutory protection where the wreck of the Grace Dieu is entombed within the riverbed. The lower stretches of the river have been developed where yachting and marina facilities have made strong demands for water frontage. The traditional boatyards are well-used but, fortunately, there are few other modern industrial activities on the river. Bursledon, once a notable centre for the construction of 18th and 19th Century wooden ships is now in decline. 3. CONTEMPORARY COASTAL PROBLEMS Within the river, saltmarshes are retreating, possibly due to the reduction in Spartina grass. Modern housing has reached towards the river and residences are at risk from flooding. The undeveloped stretches of the river are important habitats for wildlife. These require protection from pressures imposed by development and increased use of the river. Sea-level rise poses a flood threat in the lower Hamble. This could effect both human occupation and wildlife habitats. Further dredging in the river would cause the loss of archaeological and palaeo-environmental resources in both the river bed and the intertidal margins. The shoreline management plan of 1998 anticipates flooding in the Hamble river. This poses a threat to waterfront properties at Hamble and Bursledon. However, the wildlife habitats in the river need natural flooding to ensure their sustainability. 4. KNOWN HISTORY AND PALAEOENVIRONMENTAL SETTING The prehistoric period is well represented along the river, there are many lithic find sites representing human occupation (Hampshire SMR refs: 9799, 5988, 3308, 3314, 2059 and 6508, 6511, 2092, 15055). Three saltworking sites are recorded around Warsash and Swanwick (Hampshire SMR refs: 9762, 9763, 9764), and a fourth lies near the river mouth below Hook Point (Hampshire SMR ref: 5992). The latter is one of the oldest in the region, being dated to the Iron Age. 2

3 coast UK Hamble River, Solent region, south Romano-British settlement was attracted to the river. A significant villa site has been identified near a fork in the upper tidal reaches. This seem to have been well suited for riverine and maritime trade. A number of kiln sites (Hampshire SMR refs: 22907, 22909, 22910, 2087) have been identified in this vicinity and this suggests commercial activity linked to a riverine outlet. The villa also lies near the main Roman road running from Southampton (Roman Clausentum) along the south coast to Chichester. This road crossed the Hamble river near Curbridge. Other evidence of Roman activity is to be found on the western edge of the lower Hamble at Badnam Creek. This area has produced an impressive bronze plaque or defixio inscribed with a dedication to Neptune and Niscus (Hampshire SMR ref: 9798). This item seem to be a significant endorsement of Roman maritime interests centred on the river. The wording of the inscription seem appropriate to a local shrine or temple where the powers of Neptune and the sea was a notable pre-occupation of the riverside community. Further evidence from the Roman activity has been provided by scatters of brick, tile and pottery fragments along the river (Hampshire SMR ref: 9793). The sea-level in the Roman period would have controlled the size and type of ship which could navigate beyond the lower reaches of the river. It seems possible that lighters may have employed to extend s access into the upper reaches. The depth and topography of the river in earlier times is currently unknown. The river valley has produced little evidence of Saxon activity. There is some documentary evidence to suggest that two Danish ships ran aground in the estuary and that when the tide ebbed their crews were killed (Robinson 1987). The remains of Henry V s ship the Grace Dieu lie buried in the mudflats north of Bursledon (Hampshire SMR ref: 2094). This vessel is of great archaeological significance and has been designated under the Protection of Wrecks Act These ship remains are indicative of the maritime traffic that has been active in these waters for centuries yet, despite this one prominent example, very little has been recorded in the intertidal zone. This ship brings belongs to a time in the medieval period when the Hamble was beginning to become a focus for shipbuilding. With its rich timber resources and sheltered creeks it was natural that such an enterprise should flourish. Ships of all types and sizes were needed in the rapidly expanding ports of Southampton and Portsmouth (Plate P10a). During this period the sourthern English coastline became heavily defended and the Hamble was no exception. St. Andrews Castle was later built near the river mouth and some remains of this structure can be seen eroding on the foreshore of Hamble Common (Hampshire SMR ref: 9804). Throughout the 17th and 18th centuries large numbers of ships were built on the Hamble river to supply the navy in its seemingly constant conflicts with other nations. Some relics of this period have been researched historically and sites of interest identified (Figure P10.1). However, it was not until recently that an initiative to locate some of these sites was advanced by the Hampshire and Wight Trust for Maritime Archaeology. The financial gains of the past maritime industries of the Hamble were flaunted with the building of several large houses for successful shipbuilding families. Some of these historic buildings are, still visible today and are recorded in the Hampshire sites and monuments record. Early in the 20th century the river saw a revival of naval interests when this location was used for the testing of prototype mini-submarines. Somes remains from this period are still scattered around the river (Plate P10b, Hampshire SMR refs: 9795, 21744, 21842, 22895, 22852). 5. ARCHAEOLOGICAL AND PALAEO-ENVIRONMENTAL STUDIES AND POTENTIAL Where the upper stretches of the Hamble river have remained relatively untouched by commercial, residential or industrial interests the potential for the preservation of archaeological material is high. However, the post-medieval history of the river demonstrates that much human activity has been focused upon the Lower Hamble and it is here that the archaeological 3

4 coast UK Hamble River, Solent region, south and palaeo-environmental resources of the river are most prone to threat from modern human impact (Plate P10c). There has been little archaeological investigation on the river although its onshore environs have received some attention. The Roman site at Curbridge has been subject to minor field investigations and these suggest the presence of a notable Roman population settled around the navigable limit of the river where a pottery industry may have flourished. In the Lower Hamble there is further evidence of Roman coastal activity on the north bank in the vicinity of Badnam Creek. Roman building materials have been found here as well as a bronze defixio which was appropriately dedicated to Neptune and the water god Niscus. This latter find suggests the presence of a Roman riverside community which was essentially concerned with the powers and attributes of the sea. The archaeological potential of the inter-tidal zone has only recently been recognised, and plans for its systematic investigation are in their very early stages. The County Sites and Monuments Record holds all the current information on sites along the river yet the number of entries is relatively sparse when compared to what can be observed on the ground. Other tidal rivers in the region contain peat deposits and other sediment archives provide longterm records of local sea-level rise and coastal change. There is no reason why there should not be comparable resources in the river Hamble. 6. THE DESK-TOP ASSESSMENT SCORES They are a relatively large number of sites identified on the Hampshire Sites and Monuments Record (SMR). Many of the sites have high scores as they offer a large potential for information pertinent to climatic and environmental change through the ages. 81 sites were scored, 25 scored over 8 (Appendix P10.1). 7. CURRENT APPROACH TO IDENTIFICATION AND PROTECTION OF THE ARCHAEOLOGICAL RESOURCE Until recently there has been no initiative to increase the knowledge of the archaeological resource contained within the river and its marshes. The local Sites and Monument Record contains relatively few entries for sites within the study area, and virtually no record has been made of hulks or maritime installations which are exposed at low tide in the muds of the river. The entombment of the Grace Dieu in these muds demonstrates how culturally rich the estuarine deposits of the Hamble can be. In its role as an archaeological charity, the Hampshire and Wight Trust for Maritime Archaeology has identified this area as an appropriate target for a Hamble River Project, it is in the very early stages of planning, none the less, many maritime sites have been identified for future investigation and recording. Sites on land are protected through the Central Government planning policy advice (PPG 16) as are sites along the coastline (PPG 20). The most potentially destructive processes are subject to control under the Town and Country Planning Acts of England and Wales. Below mean low water these planning controls do not apply. The sub-tidal zone is generally owned by the Crown Estate Commissioners. However, the management and administration of the system is the responsibility of Hampshire County Council. In the Hamble the protected wreck site of the Grace Dieu, is subject to licensed controls administered by the Department of Culture, Media and Sport (Hampshire SMR ref: 2094). There is no current policy or approach in place for the identification of the palaeo-environmental resource. However, this does not preclude its study being included in the current initiatives for an examination of the river by the Hampshire and Wight Trust for Maritime Archaeology. 4

5 coast UK Hamble River, Solent region, south The palaeo-environmental resource is indirectly afforded some incidental protection within the current designation of SSIs and nature reserves. The status of these sites prohibits general interference and this fortuitously protects some areas where the potential preservation of palaeo-environmental evidence is high. Maps and charts dating back to the 16th century show little change in the course of the Hamble river. This contrasts with some other rivers in the region where their inland reaches show some notably rapid silting in the 16th and 17th centuries. An established equilibrium between the sediment budget and tidal regime has ensured there has not been large scale loss of the resource in the past. However, dredging activities in the lower stretches of the river may change the natural balance causing erosion and coastal instability. 9. SUCCESSES AND PROBLEMS IDENTIFIED BY THE LIFE PROGRAMME The river has been subject to rises in sea-level relative to land. This can be seen now that erosion and disturbance is revealing archaeological features which have been sealed beneath some of the intertidal sediments. It has been reported that parts of one Roman site some associated riverfront structures are becoming more exposed. This process, however, does not seem to be particularly rapid may be the result of an increasing incidence of higher tides. It is these high tides which pose the major risk of flooding for the population which currently occupies the flood plain of the river. The Strategic Planning Authority has been prompt to produce a Local Plan which recognises the need for an appropriate course of action to minimise the chances of further overtopping. The plan also observes that archaeological features and artifacts are not only threatened by development, but also by treasure-seekers and the ravages of time and that damage to archaeological sites should be averted both above or below the low water mark. The policies of this plan commit the Local Planning Authority to the protection and preservation of historic wrecks designated under the Protection of Wrecks Act of 1973 and other significant maritime archaeological sites. The policy also advocates that developers should ensure that prior investigation and recording will be undertaken and that the development will be designed to accommodate important maritime archaeological sites that may be discovered during the investigation. The plan also promises that local planning authorities will encourage the survey and recording of maritime archaeological sites and the conservation of important maritime remains and artifacts. 10. SOCIAL INCLUSION AND COMMUNITY INVOLVEMENT The Hamble river is the focus of considerable leisure activity, mostly through maritime-related pursuits, but also from nature enthusiasts and ramblers. Leaflets are available giving information on the river and its potential for such activities. The management of the river is overseen by the Harbour master who regulates traffic and moorings. The Harbour Master is also responsible for the distribution of information to local residents and visitors. The proposals for the formulation of a new River Hamble Management Plan have been well publicised and these call for participation from interested persons or groups.. This is currently ongoing. The proposals to instigate the Hamble River Project by the Hampshire and Wight Trust for Maritime Archaeology will involve volunteer help from members of the public who will be invited to participate in recording the archaeological resource which of their own locality. This will fulfill on of the major aims of the Trust which is to record the maritime heritage while disseminating information and promoting public awareness. 11. CONCLUSIONS AND KEY ISSUES The Hamble river is an example of a modest estuary harbouring a maritime community which has seen various episodes or economic expansion and contraction over the past 2000 years. Industrial use of the river has recently changed to recreational use. This has brought a new array of potential human impacts which threaten the sustainable management of the natural 5

6 coast UK Hamble River, Solent region, south and historic environment. These impacts are principally posed by the expansion of sailing facilities and residential development. The construction of low-level road and rail bridges over the tidal river has imposed severe restrictions on up-stream navigation. This has secured a marked benefit for the assets of the natural environment. The assets of the historic environment lie both up-stream and downstream of the bridge crossings. The future survival or loss of archaeological sites in these two contrasting locations should reveal the effectiveness or present policies. The good management of the natural environmental assets of this river has been reinforced by the national designation of Sites of Special Scientific Interest; the recognition Areas of High Nature Conservation Interest and the formation of a Local Nature Reserve. In contrast with the provisions for the natural environment, protective measures for the historic environmental assets of this river are weak. This weakness seems to reflect a common inconsistency observed elsewhere in Europe. It appears to arise from an assumption that references to the environment can only mean the natural environment. The presence of palaeo-environmental deposits or archives is strongly suspected in the river The Local Plan makes no reference to these resources and the need for their protection. There are notable historic shipwrecks in the sediments of the Hamble. The earliest, Grace Dieu dates from the 16 th century. The relative stability or instablity of historic shipwrecks such as these offers a potential means of detecting and calibrating rejuvenated erosion and other environmental changes which may be occurring in the river. The recognition and monitoring of such changes could be highly beneficial to shoreline management and the formulation of shoreline management plans and flood defence policies. 12. BIBLIOGRAPHY Hampshire County Council Hamble River local Plan. Ritchie, S 1988 The Hamble River and Much about Old Bursledon Moore, J 1987 From Nord to Tarrant - an account of some ships and shipbuilders on the River Hamble at Bursledon Robinson, N 1987 Hamble: a Village History 13. ACKNOWLEDGEMENTS Thanks are due to Andy Russel of Southampton City Archaeology Unit; the Maritime Section of the Royal Commission on the Historic Monuments of England and to the Hamble Harbour Master. 6

7 Hamble River, Solent region, south coast UK Figure P chart by Murdoch Mackenzie showing historic settlement and shipbuilding sites around Bursledon on the Hamble, prior to development in the 19 th and 20 th centuries. It also shows a broad shelf of intertidal saltmarsh and a partially submerged mid-holocene land surface, revealing coastal environmental change over the past 200 years 7

8 Hamble River, Solent region, south coast UK Plate P10a Timber revetments in this creek of the Hamble River denote medieval and post medieval maritime activity. Free of dredging, this channel has survived as a palaeo-environmental archive Plate 10b The hulks of historic wooden vessels on the shore of the Hamble River mark an un-dredged environment which has escaped development pressure Plate P10c Degradation of this ancient wooden quay at Dock Copse attests the loss of an artificial revetment to the longer timetable of shoreline change 8