Portland Works, Royal Worcester Porcelain, Portland Walk, Diglis, Worcester

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1 Portland Works, Royal Worcester Porcelain, Portland Walk, Diglis, Worcester An Archaeological Evaluation for Berkeley Homes (Oxford and Chiltern) Limited by Sean Wallis and Danielle Colls Thames Valley Archaeological Services Ltd Site Code RWP 04/65 June 2006

2 Summary Site name: Portland Works, Royal Worcester Porcelain, Portland Walk, Diglis, Worcester Grid reference: SO Site activity: Evaluation Date and duration of project: 8th 26th May 2006 Project manager: Steve Ford Site supervisor: Sean Wallis Site code: RWP 04/65 Area of site: ha Summary of results: No archaeological deposits nor finds of archaeolgoical interest were observed though the natural geology was not encountered. Most of the site appeared to have been reclaimed in the 19th century with a substantial thickness of made ground present. Monuments identified: None Location and reference of archive: The archive is presently held at Thames Valley Archaeological Services, Reading and will be deposited with Worcester City Museum in due course. This report may be copied for bona fide research or planning purposes without the explicit permission of the copyright holder Report edited/checked by: Steve Ford Steve Preston i Thames Valley Archaeological Services Ltd, De Beauvoir Road, Reading RG1 5NR Tel. (0118) ; Fax (0118) ; tvas@tvas.co.uk; website :

3 Portland Works, Royal Worcester Porcelain, Portland Walk, Diglis, Worcester An Archaeological Evaluation Introduction by Sean Wallis and Danielle Colls Report 04/65 This report documents the results of an archaeological field evaluation carried out at Portland Works, Royal Worcester Pottery, Portland Walk, Diglis, Worcester (SO ) (Fig. 1). The work was commissioned by Mr Andrew Saunders-Davies of Berkeley Homes (Oxford and Chiltern) Ltd, Berkeley House, Abingdon Science Park, Barton Lane, Abingdon, Oxfordshire, OX14 4NB. Planning permission (App no P05D0432) has been gained from Worcester City Council to redevelop the site of the Royal Worcester Porcelain works for a hotel complex and new residential apartments, with the refurbishment and reuse of other historic buildings. This permission applies to both the northern and southern parts of the Porcelain Works complex, and the planning consent is subject to three archaeological conditions (54, 55 and 56). Conservation Area consent has also been gained (App no L05D0073) with a further condition (2) for a record of the factory buildings and manufacturing processes prior to demolition. A summary of the relevant consents is presented in a brief for the project (WCM2006). The conditions attached are in accordance with the Department of the Environment s Planning Policy Guidance, Archaeology and Planning (PPG ), and the City Council s policies on archaeology. This report is wholly concerned with the field evaluation carried out in the southern part of the porcelain works known as Portland Works on Portland Walk. The development proposals for this area are for residential use and include basement car parking, for which a substantial reduced-level excavation will take place. The northern portion of the site (on Severn Street) has been subject to several stages of work already. Other reports will cover work in connection with the other conditions. The field investigation was carried out to a specification approved by Mr James Dinn, Archaeological Officer for Worcester City Council. The fieldwork was undertaken by Simon Cass, Jo Pine and Sean Wallis in May 2006, and the site code is RWP 04/65. The archive is presently held at Thames Valley Archaeological Services, Reading and will be deposited with Worcester Museum Service in due course. 1

4 Location, topography and geology The site is located in the Diglis area of Worcester, which is situated in the Severn Valley, to the north of the Severn s confluence with the River Teme. The site itself lies in the valley of a former tributary to the Severn, the Frog Brook, whose extant part now comprises part of the Birmingham to Worcester Canal. According to the British Geological Survey, the underlying geology consists of alluvium, with gravel terrace deposits of the River Severn occurring at the northern edge of the site (BGS 1993). A borehole investigation (STATS 2004) by showed that on average, made ground overlay alluvial deposits to a depth of at least 2m below present ground level. This majority of the excavated trenches, however, showed that the clays encountered at these depths were not naturally deposited. At the time of the evaluation, the site comprised an irregular parcel of land, the majority of which was occupied by a large industrial building. This was, until relatively recently, used by Royal Worcester Porcelain for the storage and finishing of various products. The site is reasonably flat and lies at a height of approximately 15m above Ordnance Datum. Archaeological background The archaeological background and potential of the site has been summarized in a brief for the project (WCM 2006) issued by Mr James Dinn, Archaeological Officer at Worcester City Museum, drawing on information presented in a desk-based assessment, small scale evaluation and watching brief during geotechnical investigation (AA 2005a; 2005b; 2005c; Morriss and Sherlock 2005). In summary, the site lies close to the confluence of the Frog Brook and River Severn (Fig. 1). Such a riparian location, especially if a terrace edge can be identified, is often one preferred for earlier prehistoric settlement and the Worcester City Historic Environment Record notes the presence of prehistoric metalwork finds recovered from the river nearby. There is also a possibility of the presence of Roman deposits on the site, perhaps associated with a river port. Roman deposits including burial are recorded both to the south of the site and immediately to the north at the Severn Street site (AA 2005b; 2005c). Also to the north, late Saxon and medieval deposits have been recorded. Prior to use as a factory, the site was used as allotments, a ropewalk, timber yard and saw mill and apparently as a dump of pottery manufacturing waste. 2

5 Objectives and methodology The purpose of the evaluation was to determine the presence/absence, extent, condition, character, quality and date of any archaeological deposits within the area of development. Specifically, these entail: to determine if archaeologically relevant levels have survived on this site; to determine if archaeological deposits of any period are present; to establish the depth of deposits above the natural geological outcrop; to determine if there are any deposits of prehistoric, Roman or later date. to determine if there are any deposits present relating to porcelain manufacturing. In the absence of archaeological deposits, palaeoenvironmental information was to be collected with regard to the nature and location of Frog Brook valley and stream, the confluence of the Brook and the River Severn, alluvial deposition and the presence of any palaeochannels of the River Severn. In order to fulfil these aims, it was determined that ten trenches, 23m long and 1.8m wide would be excavated by a 360º type mechanical excavator fitted with a toothless ditching bucket, under constant archaeological supervision. Due to the constraints imposed by the existing building, none of trenches could be excavated to their full length, and some had to be shifted slightly from their original intended positions. This was approved by the City Archaeological Officer after consultation on site. Borehole data from the periphery (outside) of the factory buildings (Stats 2004) indicated that the archaeologically relevant levels may be of the order of 1.5m 2m depth but increasing to 3m and down to 4.7m closer to the River. Therefore it was proposed that the trenches would not be excavated fully to a depth greater than 2.5m (assumed as the appropriate level for the basement foundation level). However, test pits were dug in each trench to examine a deeper profile of deposits on the site. A complete list of trenches giving lengths, breadths, depths and a description of sections and geology is given in Appendix 1. Results Ten trenches, all 1.8m wide, were excavated varying in length from 5.3m to 20.2m as shown on Figure 2. Several trenches were widened and stepped at the top to maintain stability. Trench 1 (Plate 1) Orientated east-west, This trench was 11.1m long and 2.5m deep. A test pit was dug at the east end of the trench to a depth of 3.4m. The stratigraphy in this trench comprised 0.15m of concrete over 0.15m of rubble hardcore. This in turn overlay 1.5m of made ground which sealed 0.20m of brown sandy silt, possibly a buried soil, which 3

6 contained occasional fragments of ceramic building material and clinker. Directly below this was a thin band, 0.10m thick, of red/black ash, which overlay an orange/brown sandy clay which contained occasional fragments of brick (observed in section only). This deposit was recorded to a depth of 3.4m. The natural geology was not observed in this trench, and no archaeological finds or features were recorded. Trench 2 This trench measured 19.0m in length and was 3.0m deep overall. It was aligned west-east with a test pit 4.0m long and 3.50m deep at the western end of the trench. The overall stratigraphy was 0.25m of reinforced concrete floor surface overlaying 0.35m of rubble hardcore. This in turn overlay 2.90m of made ground, which comprised mottled dark brown/black sandy clay with frequent glass bottles and glass fragments, brick, pottery and clinker. A cut, filled with the made ground, was observed in the north-facing section of the test pit. This cut truncated a greenish grey silty clay deposit which contained moderate quantities of brick, pottery and coal (not retained). No archaeological finds or features were observed in this trench and natural geology was not encountered. Trench 3 This trench was aligned north west- south east and was 10.7m long and 2.6m deep. A test pit was excavated at the northern end of the trench to a depth of 3.5m. The upper stratigraphy of this trench was similar to the previous trenches with 0.25m of reinforced concrete over 0.35m of rubble hardcore which in turn overlay 1.7m of made ground/demolition rubble. This layer sealed a deposit of dark bluish grey silty clay, recorded to a depth of 3.5m, which contained occasional organic inclusions though it is uncertain if this is alluvium or a further episode of made ground. Concrete foundations with steel girders were observed along the eastern edge of the trench and may be foundations for the current building or perhaps a slightly earlier structure. A cut was also observed at the southern end of the trench, similar to the cut observed in Trench 2. Trench 4 (Plate 2) This trench was 5.3m long and 2.50m deep overall, and was aligned north east- south west. The stratigraphy consisted of 0.25m of reinforced concrete floor surface, overlying 0.35m of rubble hardcore, which in turn overlay 1.80m of made ground, comprising 19th- and 20th-century detritus, large amounts of pottery, glass and ash (not retained). In the test pit at the north end of the trench a second deposit of made ground was observed from 2.50m to a depth of 3.60m at the base of the test pit. This comprised dark blue grey silty clay and, as in 4

7 other trenches, contained fragments of brick, pottery and coal (which were not retained). No finds or deposits of archaeological interest were observed and the natural geology was not observed. Trench 5 (Plate 3) This trench was 10.0m long and 2.5m deep overall, and was aligned east-west The stratigraphy showed 0.25m of reinforced concrete floor surface overlaying 0.35m of rubble hardcore. This in turn overlay layers of made ground 1.50m thick, mainly comprising 19th- and 20th-century domestic waste, glass and china fragments. This overlay a deposit of dark blue grey silty clay with brick and transfer-printed china fragments, which the test pit at the east end exposed to a depth of 3.50m. No finds or deposits of archaeological interest were observed. Trench 6 This trench was aligned south west- north east and was 20.2m in length and 2.6m deep. It was excavated to 3.6m in a test pit at the south-west end. The stratigraphy comprised 0.30m concrete overlying 0.35m of rubble hardcore make up over 2.25m of made ground containing 19th- and 20th-century bottles and jars. This layer of made ground sealed a dark blue grey silty clay, observed in the test pit only, which contained occasional fragments of 19th- and 20th-century china. Close to the north-east end of the trench, the blue clay was truncated by dumps of made ground which contained occasional fragments of china and coal; this again appears similar to the cuts observed in Trenches 1 and 3. Natural geology was not recorded in this trench and no finds or features of archaeological significance were observed. Trench 7 (Plate 4) This trench was aligned South west- north east and was 14.10m in length and 2.7m deep overall, with a test pit at 4m from the south-west end taken to a depth of 3.50m (Fig. 4). A brick-built drain caused the trench to be stepped up from 8.5m to 11m. The stratigraphy showed 0.25m of reinforced concrete floor surface overlaying 0.35m of rubble hardcore. This in turn overlay made ground, comprising distinct bands of demolition rubble with only occasional glass and pottery fragments, observed to a depth of 3.50m. No finds or deposits of archaeological interest were observed Trench 8 Aligned south west- north east, this trench measured 10.1m in length and 2.7m deep, with a test pit excavated at the north-east end to a depth of 3.70m. The stratigraphy comprised 0.30m of concrete over 0.30m of rubble 5

8 hardcore. This overlay a made ground deposit, 1.5m thick, which sealed a dark grey silty clay deposit, recorded to a depth of 3.70m, which contained fragments of brick and architectural stone. In the north-east facing section of the test pit a clean reddish brown sand and gravel was observed. This deposit is thought to be redeposited natural geology as the dark grey silty clay appears to be tipped against it as opposed to overlying it. No archaeological finds or features of interest were observed and the natural geology was not observed in this trench. Trench 9 This trench was aligned north east- south west, 7.1m long and 2.6m deep. A test pit was dug at the south end to a depth of 3.4m. The stratigraphy was generally similar to the other trenches with concrete, 0.25m thick, overlying 0.35m of rubble hardcore which in turn overlay 1m of made ground. Below the made ground a dark bluish grey clay was recorded, 0.90m thick, containing ash and brick fragments (but no domestic waste this time) and this deposit sealed a dark grey brown sandy clay and gravel which also occasional brick fragments, chain and coal. In the test pit this layer was observed to be approximately 0.40m deep and overlay a brown/grey silty clay with very occasional brick fragments. No archaeological finds or features of interest were recorded and the natural geology was not observed in this trench. Trench 10 The final trench was 6.3m in length, 1.6m deep and orientated SE NW. This trench proved difficult to excavate due to lack of space and its close proximity to the main access road. Concrete footings were observed truncating the entire south-east edge of the trench; these are most likely associated with a basement. Where the trench was not truncated the stratigraphic sequence observed was 0.20m of Tarmac and concrete, overlying 0.20m of rubble hardcore. This overlay 0.70m of made ground which in turn sealed a reddish/brown sandy clay, 0.50m thick, containing 19th- and 20th-century pottery. The excavation of this trench was stopped at this depth as it was impossible to continue without the complete removal of concrete footings. No archaeological deposits or finds were observed and the natural geology was not observed. 6

9 Finds Fragments of ceramic building material, pottery and glass recovered from the trenches were readily identified on site as consistently of 19th- and 20th-century dates; a small representative sample has been retained temporarily but will be discarded. Conclusion The site is located on land that appears to have been built up and levelled extensively, possibly during the 18th century and certainly during the 19th and 20th centuries. This is consistent with known patterns of land use on this site, and the development of the local waterway system from the 1790s onwards. The combination of domestic and industrial waste and fine silts and clays encountered throughout the deposits on the site supports the evidence for levelling given by the borehole survey. Considerable quantities of silts and clays may have been imported from the Frog Brook or the associated stretch of the Birmingham to Worcester canal after phases of dredging or cleaning, and used to level the site. None of these deposits represents a former course of the Frog Brook or the Severn and none is a naturally laid alluvium. If any archaeological deposits survive on this site from the medieval period or earlier, they will lie beneath the relatively recent deposits encountered in this evaluation. As such the foundations of any development proposals which are largely or wholly located with these modern deposits, such as the basement proposed for the specific development project which instigated this evaluation, will have little or no impact on any buried archaeological deposits even if present. References AA, 2005a, Portland Walk, Worcester, an archaeological desk-based assessment, Archenfield Archaeology, WCM , Fownhope AA, 2005b, The archaeological evaluation of Royal Worcester Porcelain, Severn Street, Worcester; Stage 1, Archenfield Archaeology, WCM , Fownhope AA, 2005c, The archaeological evaluation of Royal Worcester Porcelain, Severn Street, Worcester; Stage 2, Archenfield Archaeology, WCM , Fownhope BGS, 1971, British Geological Survey, 1:50000, Sheet 199, Solid and Drift Edition, Keyworth Morriss, R K and Sherlock H, 2005, Re-development of surplus land at the Royal Worcester Porcelain Factory, Worcester, The archaeology of the Portland Walk and Severn Street sites, Archenfield Archaeology PPG16, 1990, Archaeology and Planning, Dept of the Environment Planning Policy Guidance 16, HMSO STATS, 2004, Royal Worcester Site, Severn Street and Portland Walk, Worcester, Geotechnical and Geoenvironmental Report, STATS Ltd, report 34281/02, St Albans WCM 2006, Brief for archaeological mitigation (including evaluation), Royal Worcester Porcelain site, Portland Walk, Worcester, Worcester City Museum Archaeology Section Brief 06/5 7

10 APPENDIX 1: Trench details 0m at S or W end Trench No. Length (m) Breadth (m) Depth (m) Comment test pit m Reinforced concrete, m Rubble hardcore; m made ground; m mid brown sandy silt with occasional brick fragments and clinker; m thin layer of red/black ash; m mid orange browns sandy clay with very occasional ceramic building material. No archaeological finds or features observed. Natural geology not observed. [Plate 1] test pit test pit test pit test pit test pit test pit test pit test pit m Reinforced concrete; m Rubble hardcore; m dark brown black sandy clay containing domestic debris (bottles, china, brick fragments). In test pit: m greenish grey silty clay with small brick and pottery fragments and coal. No archaeological finds or features observed. Natural geology not observed m Reinforced concrete; m Rubble hardcore; m made ground; m dark bluish grey silty clay. No archaeological finds or features were observed. Natural geology not observed m Reinforced concrete, m Rubble hardcore, m made ground containing domestic debris, m dark blue grey silty clay with occasional coal, pottery and brick fragments. [Plate 2] m Reinforced concrete, m Rubble hardcore, m made ground, m dark blue grey silty clay with moderate brick and china fragments. No archaeological finds or features observed. Natural geology not observed. [Plate 3] m Reinforced concrete, m Rubble hardcore, m made ground containing domestic debris, m dark blue grey silty clay with rare china fragments and coal. At 16.8m from south-west end, where the clay was reached at only 2.3m down, the made ground appeared to truncate the clay. No archaeological finds or features observed. Natural geology not observed m Reinforced concrete, m Rubble hardcore, m bands of made ground comprising largely demolition rubble. No archaeological finds or features observed. Natural geology not observed. [Plate 4] m Reinforced concrete; 0/ m rubble hardcore; m made ground; m dark grey silty clay with brick fragments. No archaeological deposits or features observed. Natural geology not observed m Reinforced concrete; m Rubble hardcore; made ground; m Dark bluish grey clay with occasional ash and brick fragments; Dark grey brown sandy clay with occasional brick fragments; m mid brownish grey silty clay with very occasional brick fragments m Reinforced; m rubble hardcore; m made ground; m mid reddish brown sandy. No archaeological features or finds. Natural geology not observed. 8

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