Evaluation by M Saywood of SCAU recorded no finds or features of archaeological interest.
Watching brief by W Weller and M Saywood of SCAU during ground level reductions for the installation of an anaerobic digestion facility revealed that the area was deeply disturbed, with made-ground comprising large amounts of 20th century waste. No finds or features of archaeological interest were revealed.
Watching brief by W Weller of SCAU conducted in 2016 during the replacement of the school swimming pool building and within the boundary of the Scheduled Monument, failed to expose the archaeological horizon. No finds or features of archaeological interest were revealed.
Strip, map and record excavation by T Collie of SCAU, undertaken in 2016, revealed a complex, Middle–Late Bronze Age/Early Iron Age system of ditches across the east of the site. Oriented north–south/east–west and in places formed of a double ditch, it extended to the centre of the site, where the principal ditch turned west towards the river Ash. The ditches may represent a domestic enclosure, although their generally shallow nature suggests they form part of the wider Bronze Age field system known to extend across a large area of the river Thames gravels both north and south of the river.
Evaluation and excavation by M Edmunds, A Haslam and P Jorgenson of PCA carried out prior to and following the demolition of the former shops and residences fronting the High Street (Historic Building Recording: SyAC 101, 222). Staines-upon-Thames is located above a series of low-lying gravel islands within the flood plain of the middle Thames valley, on the north bank of the river Thames at its confluence with the braided tributary channels of the rivers Colne and Wraysbury.
Evaluation by R Woolley of Formation Archaeology revealed a large subterranean water cistern of late post-medieval date but no finds or features of archaeological interest.
Evaluation by A Haslam of PCA following demolition of the former aerospace works revealed archaeological features in the form of parallel ditches and several small pits. The fills of all the features were largely sterile, with only one pit producing pottery and pantile fragments from the late 18th to early 19th centuries. The lack of earlier, residual, material suggests that none of the features is likely to pre-date the late post-medieval period.
Archaeological monitoring by T Collie of SCAU revealed no finds or features of archaeological interest.
A magnetometry and earth resistance survey by R and S Ainslie of Abingdon Archaeological Geophysics within the boundary of the Scheduled Monument revealed three anomalies of possible archaeological origin. A subsequent test pit evaluation by W Weller of SCAU revealed a segment of a possible early medieval ditch towards the north of the site and confirmed that some areas to the south of the site had been truncated by recent quarrying.
A trial trench evaluation by K Bower of PCA revealed a number of probable planting holes and a spread of material, all of post-medieval date but no finds or features of archaeological interest.