Oxford Flood Alleviation Scheme

Archaeological Evaluation Report
Document 1: Main Text
The Oxford Flood Alleviation Scheme (FAS) is located to the west and south of Oxford (from
just north of Botley Road to the south of Old Abingdon Road, and takes in areas to the east of
Abingdon Road). The FAS crosses two administrative districts; the Vale of the White Horse
(Oxfordshire County Council) ‐ the southern section, and the City of Oxford (Oxford City
Council) ‐ the northern section. It comprises the construction of a principal two‐stage relief
channel, designed to look and function as a natural living river, containing water all year
round. Associated elements of the FAS include drainage ditches, flood bunds, culverts and
temporary works such as construction compounds.
Following on from previous heritage asset focused work (Desk‐based Assessment, bespoke
and reactive geoarchaeological surveys, geophysical surveys, and an archaeological
evaluation on Old Abingdon Road), Oxford Archaeology (OA) was commissioned by CH2M to
undertake an intrusive trench‐based archaeological and geoarchaeological evaluation along
the route of the Environment Agency’s proposed Oxford Flood Alleviation Scheme (FAS). The
scope and design of the evaluation took an iterative approach with results from the previous
studies. The fieldwork and report writing took place between August 2017 and January 2018.
The results, build upon previous work, and have been organized into thirteen
Geoarchaeological Zones (numbered I – XIII), which relate to the underlying topography of the
area, and offer a framework for a coherent understanding of the full range of archaeological
and geoarchaeological discoveries.
Although there was a general paucity of artefactual evidence, and many features remain
undated, an extensive and targeted programme of soil and sediment sampling from both
archaeological features and geoarchaeological palaeochannels and alluvial sequences was
undertaken and allowed for a comprehensive set of radiocarbon dates (28 No.) to be obtained,
giving an almost unbroken c 8,000 year chronology spanning the Mesolithic to the Modern
periods.
Archaeological Evaluation Report
Document 2: Appendices
Archaeological Evaluation Report
Document 3: Figures and Plates
Oxford Flood Alleviation
Scheme, Field 3
Archaeological Evaluation Report
The Oxford Flood Alleviation Scheme (OFAS) is located to the west and south of Oxford, from
just north of Botley Road to the south of Old Abingdon Road, and takes in areas to the east of
Abingdon Road. The OFAS crosses two administrative districts: The Vale of the White Horse
(Oxfordshire County Council) in the southern section, and the City of Oxford (Oxford City
Council) in the northern section. It comprises the construction of a principal two‐stage relief
channel, designed to look and function as a natural living river, containing water all year
round. Field 3 falls within the associated construction works proposed for the scheme and will
be developed for a compound.
Following on from previous heritage asset focused work (Desk‐based Assessment, bespoke
and reactive geoarchaeological surveys, geophysical surveys, and an archaeological
evaluation on Old Abingdon Road and along the proposed route of the scheme), Oxford
Archaeology was commissioned by VolkerStevin Ltd on behalf of the Environment Agency to
undertake an archaeological evaluation within Field 3, a possible location for a construction
compound. The scope and design of the evaluation took an iterative approach with results
from the previous studies. The fieldwork and report‐writing took place between July and
October 2020.
The results of the Field 3 evaluation build upon the results of previous work which had been
divided into different Geoarchaeological Zones that relate to the different topographic
characteristics of the area studied. This offered a framework for a coherent understanding of
the full range of archaeological and geoarchaeological discoveries. Field 3 covered two of
these Geoarchaeological Zones. Zone VII, in the north‐east third of the area, is within the valley
floor. This zone is characterised by relatively level ground and high elevations in the surface of
the underlying Northmoor Gravel, which is covered by various thicknesses of alluvium
associated with relict and existing watercourses and channels. Zone XI, in the south‐west twothirds
of the area, is on the lower western valley slopes where ground levels start to rise above
the floodplain and sediments are dominated by colluvial ploughwash. Within Field 3 these two
Geoarchaeological Zones were divided by an existing Thames Water drainage culvert.
The archaeological results identified surviving archaeological deposits and features principally
dating from the early‐middle Iron Age, Roman and medieval periods, as well as numerous
undated features. The evidence can be viewed as corroborating and developing the
information and conclusions in relation to Geoarchaeological Zones VII (characterised by
alluvial environments in the valley floor) and Zone XI (characterised by colluvial environments
on the valley slopes) from the 2017 evaluation (OA 2018). The significant archaeological
horizon at which archaeological features are first encountered was encountered at varying
depths between 0.30m and 0.80m below the existing ground level.
Datable pre‐Iron Age activity was limited to a handful of residual pieces of flintwork, many of
which were either undiagnostic or broadly attributable to the Mesolithic/Neolithic. It is
probable that some of the undated features date to the Bronze Age or earlier and reflect the
pattern seen in the 2017 evaluation.
Evidence for Iron Age activity continues northwards along the valley slopes (Zone XI) and in
the valley floor (Zone VII). The ditches probably relate to land divisions and agrarian uses of
the wider landscape within which there is evidence for roundhouses belonging to dispersed
settlement, perhaps farmsteads. The absence of late Iron Age evidence in this area is notable.
The work in Field 3 revealed further and more compelling evidence that there was a link
between settlement activity on the slopes of the valley (Zone XI) to agricultural and/or
pastoral activity along those same slopes and extending into the valley floor (Zone VII). A
continuation of a probable NE–SW orientated routeway, evaluated in 2017, was revealed to
extend up‐slope beyond the cropmark features. Material culture such as pottery, animal bone
and charred plant remains as were found in 2017 confirm settlement, agricultural and
pastoral activity. The volume of this material combined with the Roman glass, a Harlow
brooch, ceramic building material, and the rotary quern stone represent material classes not
previously recovered. This strongly indicates that significant Roman settlement activity is
present within or very near to this area of the site. This evidence for settlement, the routeway
and enclosure (OA 2018) are set within a network of parallel and perpendicular boundary
ditches probably representing contemporary field systems.
The geoarchaeological results identified an undated paleochannel in Zone VII. Overlying the
upper deposits of the paleochannel were several trackways. Whilst no dating was recovered
it is anticipated that these are continuations of surfaces seen in 2017 and date to the late
Saxon–medieval periods. A single medieval ditch was also identified