Case Study: EUN 035 Wash Pits Field, Euston, Suffolk

Suffolk Archaeology (as the Suffolk County Council Archaeological Service Field Team) undertook the excavation of a local post-medieval brick-making site at Euston, Suffolk in the summer of 2014, in advance of the creation of a farm reservoir. The project followed phases of desktop, geophysical and trial trench survey which had identified two kilns and associated clay quarry pits, settling ponds and drainage networks, all thought to be associated with the rebuilding of the Euston Estate manor house and other buildings in the 17th and 18th centuries. Two extant ponds were presumed to be the eponymous ‘wash pits’, which were used in the clay purification process…

This project demonstrates how the apparent potential and importance of a site is sometimes established incrementally, and how early investigation and consultation can aid the creation of a suitable mitigation strategy to deal with a sites heritage assets while continuously keeping the client informed as to the implications and associated costs of dealing with such heritage assets.

Stages of investigation

1836 estate map of Euston Park, Suffolk

Suffolk Archaeology was first involved with this project, the proposed creation of a new agricultural reservoir and encompassing bank on open pasture farmland, at the pre-application stage in 2012. Following National Planning Poilcy Framework guidance and a request from the SCC Archaeological Service Conservation Team (SCCAS/CT), the archaeological advisor to the St Edmundsbury planning authority, we were commissioned by the Euston Estate to prepare a desk-based assessment of the site in support of an Environmental Impact Assessment.


The desktop study of the Suffolk HER and publically available documentary and cartographic sources suggested that there was a moderate to high potential for encountering archaeological remains of prehistoric, Roman and Anglo-Saxon date. In particular it showed that the site once lay within Euston Park although, apparently having been wooded before being cleared to farmland, it was not thought to have much potential for post-medieval archaeological deposits. The presence of two small ponds however, which gave the field name ‘Wash Pits’, was unexplained, although wash pits are associated with the brick-making industry and a nearby brick kiln was noted on historic mapping.

Plot of geophysical survey results, Euston Park

Based on the desktop assessment a Brief for geophysical survey was produced by SCCAS/CT as the next stage of works to establish the site’s potential for heritage assets. Having been appointed by the Euston Estate a written scheme for magnetometer survey of the field, which Suffolk Archaeology arranged via a sub-contractor, was submitted, approved and then carried out in full. The survey revealed nine discrete positive anomalies which were thought to be of probable archaeological origin, six narrow weak positive linear anomalies which were thought to be land drains, and several large areas of magnetic disturbance which were noted as being of intriguing shape and form and of possible archaeological origin.


A final stage of assessment of the sites’ heritage assets, a trial trench archaeological evaluation, was subsequently specified in a Brief by SCCAS/CT. Again appointed by the client Suffolk Archaeology submitted a written scheme for approval and then excavated a total of forty-five trenches across the site, with many being targeted to examine the various geophysical anomalies. While evidence for early activity on the site was identified, with two small areas containing ditches and a pit of Roman date, this proved to be limited and it was instead a somewhat unexpected phase of post-medieval activity that was of primary interest.

Exposing the surface of a kiln during the evaluation phase, Euston

The evaluation demonstrated the presence of a surprisingly complete example of a local brick-making industry in the mid-late 17th and early 18th centuries. Many of the geophysical anomalies were shown to relate to the quarrying of clay and subsequent firing of bricks, with various quarry pits and the well-preserved subterranean structure of two kilns being recorded. The eponymous Wash Pits therefore appeared to form part of the clay purification process and evidence for associated drainage was also identified.

The presence of the two kilns was unusual and represented rare surviving examples of Suffolk kilns, despite these once having been relatively common structures on country estates. It was suggested that they may have been short-lived, producing bricks for the rebuilding of the manor house and estate buildings in the 17th and 18th centuries and, with a widespread pattern of small ponds (also possible wash pits) in the vicinity, may have been part of a wider brick-making industry.


Based upon the evaluation and earlier surveys of the site SCCAS/CT advised the planning authority that, whilst preservation of the archaeological deposits in situ was not merited, further fieldwork would be required by condition on any planning consent to ‘preserve by record’ the site’s surviving evidence for post-medieval activity and Roman occupation, as these deposits would be totally destroyed by the reservoir’s development.

Following the granting of planning consent with such a condition the Euston Estate appointed Suffolk Archaeology in 2013 to submit a Project Design for a strip and map excavation of much of the site, concentrating on the excavation of the two kilns and their potential for addressing topics in the regional research agenda. Following its approval by SCCAS/CT the fieldwork was carried out in summer 2014.

Time lapse photography taken during the excavation of kiln 0229

Excavation results

The site appears to have been a self-contained industry, with two phases of quarrying and brick making activity in the 16th century and late 17th/early 18th century. Clay was quarried onsite, processed in order to remove any impurities by wetting and mixing in wash pits before being screened into settling ponds, and then excavated once more for shaping in wooden moulds, drying and firing.

17th century brick kiln at Euston, Suffolk

The first kiln 0228 has been dated to the 16th/17th century based on the dimension of bricks. The main structure was rectangular in plan, aligned north-west to south-east, and measured 7.35m x 3.9m. The alignment of the kiln was identical to that of the later kiln 0229, suggesting that this was a deliberate choice, perhaps to avoid the prevailing wind. All that survived of the kiln was the subterranean structure (to approximately 0.7m below ground level); the above ground walls and roof having been razed sometime after the structure fell into disuse. The remains included three external walls with two internal fire box chambers divided by a spine wall. Several partially intact double archways (making up the kiln bars onto which the green bricks were stacked) still survived, capping the top of the fire box chambers and running widthways across the structure. Originally there would have been twelve (or possibly thirteen) of these double archways. A drain was also set into the base of the chambers that emerged at the north-west end and extended for some distance. The north-west to south-east outer walls extended beyond the north-west extent of the fire chambers by c.2m, and served to shelter the open end of the kiln.

17th century brick kiln at Euston, Suffolk

There was no regular or clear bond for much of the kiln’s brickwork and the bricks were slightly irregular. The depth of 5 courses was c.0.36m and these were generally bonded using clay, although the firing of the kiln was so intensive that it was not always clear whether mortar had been used instead, particularly in structurally complex components such as the archways.The bricks making up the structure were red and not frogged, measuring on average 226mm-236mm long x 114mm-119mm wide x 53mm-56mm thick. The floor of the kiln was made up of natural clay, which had been so intensively heated and mixed with ash that it had become very dark red-black in places. This surface was concave in both fire box chambers; a result of having been raked after each firing of the kiln. 0228 was back-filled with a series of mixed demolition, topsoil and ash fills, with high quantities of brick and tile rubble in places and ashy deposits at the base. The rake out pit/spread of redeposited ash and brick wasters for the kiln formed a roughly circular shape around it, but on its north-west edge it extended outwards c.45m.

The second kiln, 0229, was larger and dated to the late 17th/18th century. Measuring 9.56m long and up to 4.95m wide it was also built in a more elaborate and robust way, with improvements to the design as well as a general increase in the thickness of the walls. As with kiln 0228 there were three external walls and two fire box chambers with kiln bar archways divided by a spine wall. The entrances/stoke holes to the kiln however were enclosed by a wall and the construction incorporated two tunnels which served to further shelter the kiln during firing, allowing a more regulated flow of air into the fire box chambers. The tunnels were also tied into an ancillary wall further to the north-west that served to support them and other additions included two brick plinths possibly forming post pads for fire doors, a large rectangular brick plinth of uncertain purpose son top of the spine wall and a brick floor throughout.

A number of repairs, some quite extensive, apparent and the internal walls and floor showed signs of wear. This suggests a longer lifespan than for kiln 0228, or at least that kiln 0229 was used more intensively. The large kiln would have been capable of producing significantly more bricks and tiles from each firing and may have remained in use for a longer period, indicating the increased use of bricks and tiles for construction at this time of the estate.

18th century brick kiln at Euston, Suffolk

18th century brick kiln at Euston, Suffolk

The two kilns are examples of the Suffolk type, a specific design of up draught kiln used widely within much of East Anglia throughout the late medieval period and well into the post-medieval period. They could not be fired continuously as some of the later types of kiln could be, but instead had to be raked out and left to cool to retrieve the fired products between each use. Their main advantage however was their efficiency, which was greater than that of some other contemporary kilns.

Approximately six different types of quarry pit were recorded during the excavation. Of particular interest are the ‘stanks’, quarry pits that were either regular or irregular channels. These represented approximately the amount dug out each season, typically by a single excavator. The area surrounding Kiln 0229 had a notably greater density of quarrying than that around Kiln 0228, which is in keeping with its assumed higher rate or production. The smaller irregular pits are presumed to be relatively early, dug by a smaller workforce reflecting the lower production from the 16th century kiln.

The origin of the field name ‘Wash Pits’ had been assumed to have derived from the two extant ponds on the site. However approximately 84m west of Kiln 0228 was a large silted deposit, c.34m long (east to west) and c.29.5m wide, with a poorly defined channel running from the silted deposit into one of the extant ponds. The silt spread was shallower than the pond and as such has been interpreted as the actual wash pit, with the surviving feature being a settling pond to overwinter the clay. The second pond, which lay 45m west of Kiln 0229, was shown on the 1883 Ordnance Survey as being two distinct features and so may have been a similar arrangement of wash pit and settling pond.

Following completion of the fieldwork SCCAS/CT advised the planning authority that the archaeological condition be partially discharged, allowing the development of the reservoir to commence. The post-excavation draft assessment of the fieldwork has since detailed the work required to complete an analytical report and publication of the site in an appropriate journal. Further analysis such as archaeomagnetic dating results will hopefully help to establish the period and duration of each kin’s use, and their relationship to the development of Euston Estate. Once provision for this final analysis with the client has been agreed the planning condition will be fully discharged.