Marinarkeologi inför Hamnstaden

Transkript

1 Marinarkeologi inför Hamnstaden Arkeologisk utredning Lidans mynning och del av Kinneviken Lidköpings socken och kommun Matthew Gainsford & Delia Ní Chíobháin Enqvist Bohusläns museum Rapport 2015: 17

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3 Marinarkeologi inför Hamnstaden Arkeologisk utredning Lidans mynning och del av Kinneviken Lidköpings socken och kommun Bohusläns museum Rapport 2015 :17

4 ISSN Författare Matthew Gainsford & Delia Ní Chíobháin Enqvist Grafisk form Gabriella Kalmar Layout och teknisk redigering Nina Balknäs Omslagsbild Foto taget av Delia Ní Chíobháin Enkvist. Lidköpings hamn från väster. Tryck Bording AB, Borås 2015 Kartor ur allmänt kartmaterial, Lantmäteriverket medgivande Bohusläns museum Museigatan 1 Box Uddevalla tel , fax

5 Innehåll Innehåll...3 Svensk sammanfattning...6 Background...6 Landscape...7 Natural landscape...7 Cultural landscape and previous investigations...7 Stone caissons...9 Foundation piles...9 Port quays...9 Ship remains...10 Historical source material...10 Method...12 Results...14 Conclusion and recommendations...14 References...15 Litterature...15 Tekniska och administrativa uppgifter...16 Appendicies...17

6 4 Bohusläns museum Rapport 2015 :17 Figure 1. Excerpt from Sverigekartan with the surveys location marked. Figur 1. Utdrag ur Sverigekartan med platsen för utredningen markerad.

7 Marinarkeologi inför Hamnstaden 5 Figure 2. Excerpt from GSD Property map. Overview of the survey area. Scale 1: Figur 2. Utsnitt ur GSD-Fastighetskartan. Utredningsområdet är rödmarkerat. Skala 1:

8 6 Bohusläns museum Rapport 2015 :17 Svensk sammanfattning På uppdrag av Lidköpings kommun har Bohusläns museum i samarbete med Vänermuseet utfört en arkeologisk utredning av ett vattenområde som berörs av projekt»hamnstaden«i Lidköping. Arbetet delades upp i två moment. Det första momentet omfattade sonarkartering av det berörda området samt en granskning av insamlat sonardata. Detta resulterade i att sammanlagt 13 sonarindikationer bedömdes vara av arkeologiskt intresse i Kinneviken och i Lidan. Moment 2 omfattade dykande besiktningar av samtliga indikationer samt provgropsgrävning i Kinneviken. Ingen av sonarindikationerna visade sig vara av arkeologiskt intresse, och provgropsgrävningen kunde inte påvisa några kulturlager eller andra förhistoriska boplatsspår. Bohusläns museum har ingen antikvarisk erinran då utredningen inte resulterat i några lämningar eller fynd av antikvariskt intresse. Background Lidköpings kommun have tabled a plan to realise the building project»hamnstaden«, Lidköpings city; an area of approximately square meters that encompasses the western side of Kinneviken and the lower reaches of the river Lidan; the western harbour and marina up to the western boundary of the Krono- Camping campground. Lidköpings kommun contracted Bohusläns museum to conduct an archaeological survey of the proposed development area based upon Länsstyrelsens action ( dnr ). Survey included side scan sonar mapping of the development area in its entirety, followed by diver inspections of resulting sonar anomalies. The existing small boats harbour was not however surveyed. Surveyable area was divided into two areas: UO1 in Kinneviken and UO2 in Lidan. The purpose of the archaeological survey was to determine the presence of unknown cultural sites within the development area and to identify possible damage that might occur as a result of development. HydroGIS was contracted by Bohusläns museum to carry out side scan sonar mapping, undertaken 11 June Diver inspections of anomalies and excavation in Kinneviken were undertaken by maritime archaeologists from Bohusläns museum and Vänermuseet on four separate occasions 18 August October A further day for diving remaining anomalies was undertaken May Known cultural sites in the area comprise of Lidköping 11: 1 and 12: 1, which are city cultural layers dated to medieval modern times, and a series of archaeological sites in Lidan.

9 Marinarkeologi inför Hamnstaden 7 Landscape Natural landscape Vänern is the third largest freshwater lake in Europe. Lidköping is situated on the lakes southern shore, at the mouth of the river Lidan, which empties into the bay Kinneviken. The survey area is located on the western side of Kinneviken and includes the lower reaches of Lidan, the western harbour and marina, up to the western boundary of the KronoCamping campground. Shallow water along the coast contains large areas of reed, while the area surrounding the marina consists of a sandy substrate. Visibility in Lidan is poor, that is, a half meter or less. This can be mainly attributed to agricultural activities along the Lidan waterscape resulting in substantial sediment transport downstream. Bottom sediments within Lidan are comprised of two strata; a thin and light, easily stirred up substrate, and a harder clay layer representing the sterile environment ( Gainsford 2009: 7 ). Cultural landscape and previous investigations Sporadic finds from prehistoric periods have been discovered in what is now Lidköping city; findings illustrate an early interest in the Lidan estuary. These artefacts that are without provenance dated either from circa BC or from the period, 10th 11th centuries AD. Artefact finds are not evident again until circa 1400 ( Petersen & Johansson 2008 ). Kinneviken estuary is a complex ancient environment which is difficult to interpret that has a large number of remains spanning different periods. Since the area of southern Vänern is sinking ( subsidence ) the potential for the existence of cultural heritage is high ( Westerdal 1980: 21 ). Direct evidence for this are, for example, a find of a circa year old stone axe in 1977 by a sport diver in Lasteviken, at a depth of six meters and the occurrence of preserved tree stubs in Kinneviken ( Peterson 2000, Sportdykaren 1977 ). Several interesting Iron Age weapons have also been located in the bay, including an iron spearhead with wood preserved in the socket ( 14 C analysis dated to 300 AD) ( von Arbin 2004: 4; Peterson 2000: 3; Westerdahl 2000: 17 ). The earliest mention of the city is in a charter from 1446, whereby Lidköping was given the same privileges as other towns in western Sweden. Building remains discovered during excavations in the city have illustrated that Lidköping 1446 was already established as a town ( von Arbin, 2004: 10, Klackenberg 1982: 11 ). Since 1997 Vänermuseet has conducted extensive inventory dives and geophysical mapping of the Lidan riverbed, most intensively between Torgbron and Wennerbergsbron. Results have revealed stone caissons, ship remains, foundation piles and port quays ( these are of yet unregistered in FMIS ).

10 8 Bohusläns museum Rapport 2015 :17 Figure 3. Excerpt from GSD Property map, leaves 8C 8i, 8C 7j, an overview of the survey area with adjacent cultural sites visible. Scale 1: Figur 3. Utsnitt ur GSD-Fastighetskartan, blad 8C 8i, 8C 7j, med exploateringsområdet samt närliggande fornlämningar markerade. Skala 1:

11 Marinarkeologi inför Hamnstaden 9 Stone caissons Using stone filled caissons was a common method of constructing wharves and bridges. Other use of caissons include loading and unloading areas for vessels and as an example on Gotland has shown, as foundations for buildings constructed on water ( Rönnby 2001; Peterson & Johansson 2008 ). Remains of up to ten stone caissons have been identified in Lidan. In 1912 a row of caissons was discovered in connection with Wennerberg Bridge. In 1998 an additional two were located by Vänermuseet that correspond with the earlier finds. They are 3 meter high, heavily eroded stone piles, encased in timbers with interlocking notches. 14 C analysis of one caisson returned a date within the period AD. Some of the remaining caissons identified in Lidan have also been dated using 14 C and dendrochronological analyses; yielding dates from 11th to 13th centuries AD ( Gainsford 2009: 9; Peterson & Johansson 2008 ). In 2009 Bohusläns museum conducted a preliminary archaeological investigation ( förundersökning) in Lidan. Finds included the remains of a stone caisson with associated brick, pottery and animal bone. The stone caisson was dendrochronologically dated to the interval AD, most likely AD, that is, the Early Medieval Period ( Gainsford 2009 ). Foundation piles Large numbers of foundation piles have been located in an area between Wennerberg and Torg bridges in Lidan. Most of the remaining piles are solitary but there are also groups of three to ten represented. Piles were most likely used as mooring poles, piers or permanent fish traps. In 1959 a large number of piles were observed during the foundation work for Wennerberg Bridge; in 1998 a sample was taken for 14 C analysis, which was dated to 1176±70 AD with a calibrated date ( 2 sigma) within the period AD. These piles are fragile and have been interpreted as a permanent fishing trap ( Gainsford 2009: 9; Peterson & Johansson 2008 ). Bohusläns museums preliminary archaeological investigation in Lidan 2009 located further foundation piles. These were interpreted as mooring piles or as parts of one or more permanent fishing traps. 14 C samples sent to Ångströmlaboratoriet received calibrated dates (2 sigma ) within the period AD ( Gainsford 2009 ). Port quays A stone mound runs along the eastern side of Lidan; it is circa 300 meters long and 15 meters wide. It covers an area that begins 20 meters north of Wennerberg Bridge extending to 20 meters south of Torg Bridge. The stone mound is composed mainly of cobblestones which range in size from 20 centimetres up to

12 10 Bohusläns museum Rapport 2015 :17 1 meter. Foundation piles that protrude from the mound run perpendicular to the river flow. It is most likely that the piles were originally upright forming a pier that functioned as a facility for loading larger vessels. In 2006 the site was dated by two 14 C samples. Samples provided dates to 1071±35 AD with a calibrated age ( 2 sigma ) within the period AD respective 1086±35 AD with a calibrated age ( 2 sigma ) within the period AD ( Gainsford 2009: 9, Peterson & Johansson 2008 ). Ship remains Outside the development area, to the north east, in Kinneviken lie the remains of two vessels, Lidköping 21 and 22. A significant amount of vessel remains have also been located in the area between the Wennerberg and Torg bridges in Lidan, again outside the development area. The largest, Lidköping 25, is carvel built and is approximately 20 metres long. The planks, which are of pine, are 20 centimetres wide and 3 centimetres thick. The frames are oak and have an inboard spacing of 25 centimetres. The site has an uncertain dendrochronological dating to the mid-1400s. In addition to Lidköping 25, three additional wrecks have been identified along with a large amount of disarticulated boat remains ( Gainsford 2009: 10; Peterson & Johansson 2008 ). Historical source material The earliest mention of the city is in a charter from 1446, when Lidköping was given the same rights as other towns in western Sweden ( von Arbin, 2004: 10, Klackenberg 1982: 11 ). Building remains discovered during excavations of the city have shown that even at this time Lidköping was an established town ( von Arbin, 2004: 10; Gainsford, 2009: 10 ). Archaeological investigations around Lidköping have begun to shed light on the early history of the town. An example of this is the foundation piles and stone caissons which were found close to the site of the current Wennerberg Bridge. The sites that have been dated to the late 1100s are interpreted as the foundations of an earlier bridge ( Peterson 2000: 6; Westerdahl 2000: 17 ). Some researchers have concluded that the earlier bridge is connected to the Skara bishop Bengt den Gode. According to surviving written sources, it is believed that he ordered a series of bridges built in Västergötland around the same period ( Westerdahl 2000: 17 ). During the course of the 1600s and 1700s, Lidköping was by far the most developed maritime city on Lake Vänern. By the mid-1800s however, the city s port facilities had become inadequate. Lidan s narrow mouth made it difficult for larger ships to gain access to town for loading and unloading; as a result this had to be performed in Kinneviken with the help of special bar-

13 Marinarkeologi inför Hamnstaden 11 Figure 4. Excerpt from GSD Property map, leaves 8C 8i, 8C 7j, an overview of the survey area with anomalies and test trenches marked. Scale 1: Figur 4. Utsnitt ur GSD-Fastighetskartan, blad 8C 8i, 8C 7j. Kartan visar det sonarkarterade området, sonarindikationer samt provgropar. Skala 1:

14 12 Bohusläns museum Rapport 2015 :17 Figure 6. HydroGIS boat used for sonar mapping. Photo: Delia Ní Chíobháin Enqvist. Bohusläns museum. Figur 6. HydroGIS surveybåt. Foto: Delia Ní Chíobháin Enqvist. Bohusläns museum. Figur 5. The small boats harbour in Lidköping, a part of the development area. Photo: Delia Ní Chíobháin Enqvist. Bohusläns museum. Figur 5. Småbåtshamnen I Lidköping, som ären del av exploateringsområdet. Foto: Delia Ní Chíobháin Enqvist. Bohusläns museum. ges. During comprehensive modernisation of the port of Lidköping was undertaken, the river mouth was deepened and stone piers and wharves were built along the banks ( Gainsford 2009: 10 11; Peterson 2000: 5; Westerdahl 2000: 17 ). Method Side scan sonar mapping was carried out by HydroGIS on June ; accompanied by a maritime archaeologist from Bohusläns museum. A total of square meters was mapped using a side scan sonar type Starfish 450F towfish ( 450 khz). The sonar s scanning range was 100 metres that covered the area with overlapping swaths. Review of the sonar data was undertaken by Delia Ní Chíobháin Enqvist in June In addition, a sonar survey undertaken several years ago by Vänermuseet was also reviewed by archaeologists in conjunction with the current project. Sonar data overlapped to some extent the proposed development area. The review was completed by Matthew Gainsford and Roland Peterson. However there are no available images of this material. Sonar anomalies were given a classification of 1 3, where 1 represents low potential archaeological significance and 3 high potential archaeological significance. The total survey area was divided into two subareas; UO1 was the area in Kinneviken and UO2 the Lidan river mouth. Sonar anomalies were surveyed by diving archaeologists to determine whether they were of archaeological significance. In the area north of the current small boats harbour a series of six

15 Marinarkeologi inför Hamnstaden 13 Point ID Easting Northing Latitude Longitude Description Size Classification , , ,6710 N ,9880 E Long object 5 m , , ,5980 N ,9170 E , , ,4630 N ,7760 E Semicircular shadow 2 rectangular objects 2,5 m 3 4x3 m , , ,3760 N ,7180 E Round object 5 m diam , , ,3540 N ,6940 E Long semicircular object 8 m , , ,3170 N ,6630 E Stone mound 10x5 m , , ,3350 N ,6800 E Stone mound 10 m , , ,3630 N ,7000 E Long semi circular object 8m , , ,3850 N ,7380 E Long objekt 12 m , , ,9905 N ,2787 E Boat-shaped object 11x5 m , , ,4596 N ,7746 E Wreck? 5,1x0,4 m , , ,4350 N ,7719 E Upright object 5x5 m , , ,9954 N ,2862 E Possible stone caisson 14,5x10,5 m 3 Table 1. Sonar anomalies from HydroGIS and Vänermuseets side scan sonar surveys. Easting/Northing in Sweref 99 TM; Latitude/Longitude in WGS84. Tabell 1. Sonarindikationerna urtagna från HydroGIS och Vänermuseets sonardata. Easting/Northing anges i Sweref 99 TM; Latitude/ Longitude anges i WGS84. Figure 7. Finds from test pits in Kinneviken. Foto Delia Ní Chíobháin Enqvist. Bohusläns museum. Figur 7. Fynd från provgropsgrävningen I Kinneviken. Foto: Delia Ní Chíobháin Enqvist. Bohusläns museum.

16 14 Bohusläns museum Rapport 2015 :17 test pits were excavated with a water dredge to ascertain if there existed remains of prehistoric settlement remains within the area. Furthermore, as an addition to the sonar mapping, material from previous mapping by Vänermuseet 2005 was also studied. All diving has been risk evaluated in accordance with Arbetsmiljöverkets föreskrifter ( AFS 1993: 57 ) as well as the diving practice that Bohusläns museum employs as standard practice. Results Sonar mapping resulted in 13 sonar anomalies of potential archaeological interest. However after diving surveys were conducted it could be determined that none of the 13 anomalies were of archaeological significance. Excavation of test pits within Kinneviken failed also to reveal any cultural layers or other submerged settlement remains, although some modern material was located within the pits. Conclusion and recommendations Bohusläns museum find after the concluded archaeological survey that further surveys or archaeological intervention are unnecessary. From an archaeological perspective the proposed development can proceed as planned. It should be noted however, if any archaeological material is encountered during the development process that Länsstyrelsen be contacted immediately.

17 Marinarkeologi inför Hamnstaden 15 References Litterature von Arbin, S Östra hamnen. Undervattensarkeologisk utredning, Lidköpings stad och kommun. Bohusläns museum Rapport 2004: 10. Uddevalla. Gainsford, M Tryckbank i Lidan. Arkeologisk förundersökning. Lidköping 11: 1, Lidan, Lidköpings socken och kommun. Bohusläns museum Rapport 2009: 33. Uddevalla. Klackenberg, H Lidköping. Rapport medeltidsstaden 33. Riksantikvarieämbetet och Statens historiska museer. Stockholm. Peterson, R Marinarkeologi i Vänern. Klinkbyggda fartyg och Lidköping i maritim miljö. B-uppsats i arkeologi. Göteborgs universitet. Peterson, R. & Johansson, L.G Innan Lidköping blev Lidköping. Marinarkeologisk undersökning av Lidan i centrala Lidköping. Vänermuseet. Lidköping. Rönnby, J Sjunket förflutet. Arkeologiska möjlighter under vatten. Runis & co förlag. Stockholm. Sportdykaren Fann 4000-årig stenyxa. Sportdykaren nr. 5. Westerdahl, C Stenålder under vatten i Vänern? Meddelanden från Marinarkeologiska sällskapet nr 2. Westerdahl, C Vänerns vrak fältinventeras och dateras. Marinarkeologisk tidskrift nr 1.

18 16 Bohusläns museum Rapport 2015 :17 Tekniska och administrativa uppgifter Lst dnr : Västarvet dnr : NOK Västarvet pnr : GE167 Län : Kommun : Socken : Fastighet : Västra Götalands län Lidköping Lidköping Vattenområde i Kinneviken och Lidan Ek. karta : 8C 8i, 8C 7j Läge : X Y Vattendjup : Koordinatsystem : 1-7 meter RT90, 2,5 gon V Uppdragsgivare : Ansvarig institution : Projektledare : Fältpersonal : Konsulter : Lidköpings kommun Västarvet Staffan von Arbin Staffan von Arbin Delia Ní Chíobháin Enqvist Roland Peterson Matthew Gainsford Thomas Bergstrand Vänermuseet, Lidköping Fältarbetstid : , Arkeologtimmar : 104 Undersökt yta : m 2 Arkiv : Fynd : Bohusläns museums arkiv Inga fynd omhändertogs.

19 Appendicies Appendix 1. Sonar anomaly images. Bilaga 1. Bilder av sonarindikationer.

20 Appendix 1. Sonar anomaly images. Bilaga 1. Bilder av sonarindikationer

21 07 10

22 11 13

23 20 21

24 24 44

25 67 70

26 87

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