Marieholmsbron. Marinarkeologisk utredning etapp 1 och 2 Vattenområde i Göta älv, Göteborgs kommun. Bohusläns museum Rapport 2013:15

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1 Marinarkeologisk utredning etapp 1 och 2 Vattenområde i Göta älv Göteborgs kommun Delia Ní Chíobháin Enqvist & Matthew Gainsford Bohusläns museum Rapport 2013: 15 Marieholmsbron

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3 Marieholmsbron Marinarkeologisk utredning etapp 1 och 2 Vattenområde i Göta älv, Göteborgs kommun Bohusläns museum Rapport 2013:15

4 ISSN Författare Delia Ní Chíobháin Enqvist & Matthew Gainsford Grafisk form Gabriella Kalmar Layout och teknisk redigering Lisa K Larsson Omslagsbild Framsidan visar Marieholmsbron mot sydväst, foto Staffan von Arbin. Baksidan visar Göta Älv, foto Staffan von Arbin Tryck Bording AB, Borås 2013 Kartor ur allmänt kartmaterial, Lantmäteriverket medgivande Bohusläns museum Museigatan 1 Box Uddevalla tel , fax

5 Innehåll Svensk sammanfattning...6 Abstract...6 Background...6 Purpose...6 Cultural environment and previous investigations...6 Method...10 Phase 1 Etapp Phase 2 Etapp Results...10 Conclusion and recommendations...10 References...12 Tekniska och administrativa uppgifter...13 Appendices...14

6 4 Bohusläns museum Rapport 2013:15 Figur 1. Utsnitt ur Sverigekartan med platsen för utredningen markerad. Figure 1. Excerpt from Sverigekartan with the area of investigation marked.

7 Marieholmsbron 5 Figur 2. Karta över utredningsområdet. Skala 1: Figure 2. Map showing investigation area. Scale 1:

8 6 Bohusläns museum Rapport 2013:15 Svensk sammanfattning Med anledning av byggnation av ny järnvägsbro vid Marieholm i Göteborg har Bohusläns museum genomfört en arkeologisk utredning i två etapper. Efter granskning av framtagen sonardata över det berörda vattenområdet i Göta älv valdes elva sonarindikationer ut då de bedömdes kunna vara av arkeologiskt intresse. Två av dessa låg inom det planerade arbetsområdet och kom att omfattas av en etapp 2-utredning. Indikationerna besiktigades genom dykning. Indikation 79, söder om Marieholmsbron, bestod av recent material som ansamlats i en grop. Indikation 85, norr om Marieholmsbron, utgör en båtlämning ( Ny 1 ). Båtlämningen bedöms vara yngre än 100 år och är således inte en fornlämning. Under etapp 2-utredningen grävdes sammanlagt sexton provgropar längs kanterna på båda sidor av älven. Femton av dessa grävdes inom det planerade arbetsområdet och en sista strax norr om området. Provgropsgrävningen resulterade endast i recenta fynd som ej är av arkeologiskt intresse. Efter avslutad utredning har Bohusläns museum ingen antikvarisk erinran mot det planerade arbetsföretaget. Abstract Prior to the construction of the new railway bridge at Marieholm in Gothenburg, Bohusläns Museum conducted an archaeological survey of the planned development area in Göta Älv. Upon completion of Phase 1 eleven side-scan sonar indications were deemed to be of archaeological interest. Two of these were within the planned development area and became the subject of a Phase 2 survey. Anomalies were examined by diving archaeologists. Anomaly 79, south of Marieholmsbron, consisted of a deposition of modern material located in a depression. Indication 85, north of Marieholmsbron, consists of the remains of a boat ( Ny 1 ). The boat remains are judged to be younger than 100 years and are therefore not classified as an ancient monument. During the Phase 2 investigation sixteen test trenches were excavated along both sides of the river. Fifteen of these were excavated within the planned working area, with the final excavated just north of the area. Test trench excavation resulted only in relative modern finds deemed to be not of archaeological interest. Upon completion of the survey Bohusläns museum have no objections to the planned work. Background Bohusläns museum, through Länsstyrelsen in Västra Götalands län, received a directive to conduct an archaeological survey of the planned development area in Göta älv. Trafikverket intends to construct a new railway bridge over Göta älv in close proximity to Marieholmsbron in the city of Göteborg. The survey was divided into two phases. Phase 1 involved the inspection of the results of a side scan sonar survey. The survey included bathymetric and geophysical surveys conducted by Marin Mätteknik ( MMT ) on behalf of Trafikverket. The archaeological survey resulted in eleven sonar anomalies that were deemed of potential archaeological interest, two of which were within the development area. These indications were tentatively interpreted as ship remains or physical structures similar to stone caissons. Archaeologists recommended that these anomalies should be inspected to determine their nature and possible archaeological status under Phase 2. Also during Pahse 2 sixteen test trenches were excavated parellel to the river banks. One of the test trenches was excavted outside of the development area. Purpose The purpose of the archaeological survey was to determine whether previously unknown archaeological and cultural remains existed the within the area of the planned development. Results of the survey are intended to serve as a basis for planning for both Länsstyrelsen and Trafikverket. Cultural environment and previous investigations Göta älv has been used as a transportation route during prehistoric and historic times up until the present day. Gothenburg has had several locations on the Göta älv estuary during the 1500s and early 1600s before the city was finally built at its present location in As with its many predecessors Gothenburg served as a port and maritime city; trading with several major ports ( Lind 1923 :16ff ). Shipping within the development area can be assumed to have been extensive, and the likelihood of locating cultural artefacts in the form of ship remains, port facilities and cultural layers was therefore considered high. Within the survey area there are no previously known maritime archaeological sites.

9 Marieholmsbron 7 Figur 3. Karta över utredningsområdet. Skala 1: Figure 3. Map showing investigation area. Scale 1:

10 8 Bohusläns museum Rapport 2013:15 Figur 4. Karta över exploateringsområdet med uttagna sonarindikationer. Skala 1 : Figure 4. Map showing area mapped by sonar and indications. Scale 1 :4 000.

11 Marieholmsbron 9 Figur 5. Karta över de aktuella indikationerna och provgroparna. Skala 1 : Figure 5. Map showing location of inspected indications and test trenches. Scale 1 :3 000.

12 10 Bohusläns museum Rapport 2013:15 However, considering the cultural landscape and historical significance of the surrounding area, the potential of underwater sites cannot be excluded. Planned development will be carried out north-east of the ancient monument site Göteborg 216 :1, which contains cultural layers from 17 th century Göteborg. The area is also bordering Göteborg 218 :1, the early site of Nya Lödöse/Nylöse, Göteborg s predecessor. Göteborg 218 :1 consists of the late medieval/early modern city remains from the period 1473 to The city of Lödöse, originally situated further upstream Göta älv, was moved to the area near Säveholmen at Säveån s estuary in The reason for this move was to avoid the so-called Bohus customs ( Bohustullen ) at Bohus fästning. Nya Lödöse is currently the area encompassed by Gamlestaden in Göteborg ( Andersson 1973 ). The city existed between the years 1473 and 1624, with the exception of the move to Älvsborgs fortress from 1547 to The city was first formed in 1473 largely by displaced inhabitants from Lödöse. The historian Sixten Strömbom oversaw dredging operations in Säveån in the area of Nya Lödöse between 1916 and The dredging yielded finds consisting of pottery ( redware, stoneware, and earthenware ), glass ( bottles, window glass ), coins, tin bowls/pans, axes, a sword hilt, a rider s gun, arrowheads and a dagger. Strömbom dated the finds to the s. He also found what was believed to be a stone caisson along the northern river bank ( Strömbom 1924 :128ff, 174 ). During excavations carried out by Göteborgs arkeologiska museum within the area of Göteborg 218 :1 ship remains and an unspecified number of stone caissons were discovered in 1971 during the construction of the nearby tram bridge ( Göteborg 452 ). Also in Säveån, downstream from the aforementioned bridge, Bohusläns museum conducted a preliminary marine archaeological investigation in The results were confined to a small amount of historical ceramics and modern pole installations ( Bergstrand 2007 ). In 2012, during works in Gamlestadstorget within the area of Göteborg 218 :1, Bohusläns museum conducted a preliminary investigation. The investigation resulted in two pole structures, a wreck site, and a small amount of ceramic finds dating from the later medieval period to the 1700s ( Bergstrand et al ). Method Phase 1 Etapp 1 A bathymetric and geophysical survey was carried out on 27 May, 2011 by MMT on the survey vessel M/S Ping. The side-scan sonar survey was performed with a hull-mounted Edge Tech side-scan sonar 4200 ( 300/600 khz ). Survey swaths ranged from 50 to 150 meters in the deeper waters around Klåvudden. Side scan data of the survey area was mostly complete, however within harbour areas side scan data was deficient. Side-scan data was reviewed by archaeologists from Bohusläns museum in June 2011; resulting in 11 sonar anomalies that were deemed to be of possible archaeological interest. Phase 2 Etapp 2 Inspections of two selected sonar indications were conducted by diving archaeologists on March All diving activities were carried out with tethered surface-supplied helmet diving and diver-surface communications in accordance with AFS 2010 :16 and the diving standards of Bohusläns museum. On 2 3 April 2012 a total of sixteen test trenches were dug. Fifteen of the test trenches were dug within the corridor outlined for development, with one located just outside the planned development ( figure 5 ). Test trenches were excavated by a mechanical excavator, upon a barge, in conjunction with Frog Marine Service ( figure 6 ). Results During Phase 2, anomalies 79 and 85 were investigated by diving archaeologists. Indication 85 proved to be the remains of an oak-built boat, possibly that of a life-boat ( Ny 1 ). The remains measured 6 meters long, 2 meters wide and 0,5 m high. It is interpreted as being built in the first half of the 1900s. Since it is less than 100 years old it is not a protected monument. The test trenches yielded modern finds only, that were deemed as not of archaeologiacl interest. Conclusion and recommendations After completing the archaeological survey it is the opinion of Bohusläns museum that no further archaeological measures are required at this site.

13 Marieholmsbron 11 Figur 6. En arkeolog gräver igenom muddermassorna från en av provgroparna. Foto Bohusläns museum. Figure 6. Archaeologist inspecting test trench material. Photo Bohusläns museum.

14 12 Bohusläns museum Rapport 2013:15 References Almqvist, H Göteborgs historia. Grundläggningen och de första hundra åren. Förra delen. Från grundläggandet till enväldet ( ). Skrifter utgivna till Göteborgs stads trehundraårsjubileum genom jubileumsutställningens publikationskommitté I. Göteborg. Almqvist, H Göteborgs historia. Grundläggningen och de första hundra åren. Senare delen. Enväldets och det stora nordiska krigets skede ( ). Skrifter utgivna till Göteborgs stads trehundraårsjubileum genom jubileumsutställningens publikationskommitté II. Göteborg. Andersson, H Nya Lödöse Gamlestaden fem hundra år. Kungsbacka. Berg, W Samlingar till Göteborgs historia. Göteborg. Bergstrand, T. ( med bidrag av S. von Arbin ) Säveån genom Gamlestaden. Arkeologisk förundersökning. Göteborg 218, Gamlestaden 740 :162 m.fl. Göteborgs stad, Göteborgs kommun. Rapport 2013 :8. Bohusläns museum. Uddevalla. Grauers, S. ( red ) Nya Lödöse tänkeböcker Skrifter utgivna till Göteborgs stads trehundraårsjubileum 6. Göteborg. Lind, I Göteborgs handel och sjöfart Historisk-statistisk översikt. Göteborgs jubileumspublikation 10. Strömbom, S Forskningar på platsen för det forna Nya Lödöse ( ). Skrifter utgivna till Göteborgs stads trehundraårsjubileum genom jubileumsutställningens publikationskommitté 5. Göteborg. Bergstrand, T I : T. Wennberg ( red ). Dubbelspåret Gamlestaden. Arkeologisk rapport från Göteborgs stadsmuseum 2007 :13. Göteborg.

15 Marieholmsbron 13 Tekniska och administrativa uppgifter Lst dnr : Västarvet dnr : VA Västarvet pnr : Län : Kommun : Socken : Fastighet : Västra Götalands län Göteborg Göteborgs stad Vattenområde i Göta älv, vid Marieholmsbron Ek. karta : 7B1e Läge : X , Y Meter över havet : Max -7 meter Koordinatsystem : Sweref 99 TM Uppdragsgivare : Ansvarig institution : Projektledare : Fältpersonal : Trafikverket Bohusläns museum Matthew Gainsford Thomas Bergstrand, Staffan von Arbin, Matthew Gainsford Konsulter : Räddningstjänsten Storgöteborg, Marin Mäteknik AB, Frog Marine Service AB Fältarbetstid : Arkeologtimmar i fält : 88 Undersökt yta : m² Arkiv : Fynd : Bohusläns museum arkiv Inga fynd omhändertogs

16 14 Bohusläns museum Rapport 2013:15 Appendices Bilaga 1. Sammanställning av samtliga sonarindikationer uttagna vid den arkeologiska utredningens etapp 1. Positioner angivna i Sweref 99 TM. Alla sonarbilder Marin Mätteknik AB. Appendix 1. Table of all sonar indications selected during the archaeological survey Phase 1. Positions listed in Sweref 99 TM. All sonar images Marin Mätteknik AB.

17 Bilaga 1.Sammanställning av samtliga sonarindikationer uttagna vid den arkeologiska utredningens etapp 1. Positioner angivna i Sweref 99 TM. Alla sonarbilder Marin Mätteknik AB. ID Klassificering Ost koord. Nord koord. Längd Bredd Höjd Tolkning Bild ,8 0,4 0,4 Möjlig fartygslämning ,1 0,3 0,1 Möjlig fartygslämning alternativt dumpad barlast ,2 0,5 0,3 Möjlig fartygslämning ,1 0,5 0,5 Möjlig fartygslämning

18 ,1 0,4 0,6 Möjlig fartygslämning ,8 1,6 0,4 Möjlig fartygslämning ,3 0,8 0,4 Möjlig fartygslämning ,2 1 0,5 Möjlig fartygslämning ,9 0,4 0,4 Möjlig fartygslämning

19 ,9 0,5 0,3 Möjlig fartygslämning ,6 2,7 1,1 Möjlig fartygslämning

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