Before the archaeologists started digging, background research was undertaken to provide clues as to the likely survival of archaeological remains on the Olympic Park site, and their vulnerability to large-scale development.
A report was produced for each of the Park’s 15 planning zones, which collated and reviewed a wide range of information about the origins and history of the site. This included data about its geology and sediments, records of archaeological finds, as well as reports from previous excavations, historical records and documents about the site. Early maps of the Lea Valley, and details of standing buildings and other structures of architectural or historical interest were also included.
Based on this information, the archaeologists, planning authorities and the ODA were able to develop a strategy for the first phase of archaeological fieldwork – the Evaluation.
Excavations were undertaken to look for archaeological remains on the Olympic Park site.
In total, 122 evaluation trenches were excavated across the Park, with a series of trenches specifically dug to locate the line of the Roman road between London (Londinium) and Colchester (Camulodunum), which is known to pass through the Park.
Many of the trenches dug were in areas covered by a considerable depth of recent deposits. To expose even a small area of the underlying archaeological layers, machine excavators often had to create large, stepped trenches, removing hundreds of tonnes of soil, so that the work could be done safely.
Under difficult working conditions – in often waterlogged and contaminated ground – the archaeologists sampled the exposed deposits, recorded features and recovered artefacts, to open a narrow window into the past.
Findings from most of the evaluation trenches suggested that there was no need for more archaeological work. However, at eight locations it was decided that further excavation and reporting was required, both to examine the archaeological remains more closely, and to mitigate the effects of the development by preserving ‘by record’, those remains that could not be preserved in the ground.
A dense cluster of archaeological features indicating a long-term prehistoric settlement was found in evaluation Trench 9. Based on these finds, the trench was extensively enlarged and revealed a Middle Bronze Age (1600–1100 BC) field system, Late Bronze Age (1100–700) working areas, a Middle Iron Age roundhouse settlement and enclosures (400–100 BC), and a Romano-British boundary ditch of 1st century date.
In contrast, Trench 59 only needed to be slightly enlarged in order to allow the full excavation and recovery of a 19th century river boat partly exposed during the evaluation.
Following a site-wide assessment of the findings from all the trenches, the results of the fieldwork have undergone a detailed analysis and interpretation.
The finds have been cleaned, sorted and samples processed and, along with the written site records, drawings and photographs, are being closely examined. The aim was to build up a picture of when and how past occupants of the Lea Valley lived, worked and died, to better understand the development of the local and the wider community.
A number of community-based projects have already enabled members of the public to get involved with the archaeology and built heritage of the Olympic Park, and results of the analysis of the finds are also being made widely available to the local community and general public, as well as researchers.