The World’s First Iron Framed Building

Case Study

ESI, now part of Stantec was commissioned by Feilden Clegg Bradley Architects to carry out a contaminated land assessment of the Ditherington Flax Mill site in Shrewsbury, known locally as the Shropshire Maltings.

The Ditherington Flax Mill site in Shrewsbury is of major regional and national importance not least because the mill building was the world’s first commercial structure to be constructed around an iron frame. Nearly 200 years of industrial occupancy, prior to the closure of the Flax Mill (and subsequent Maltings) in 1987, offered significant potential for land contamination. The regeneration of the site was therefore a prime objective for both English Heritage and Shrewsbury and Atcham Borough Council.


The assessment of the site was conducted by combining a number of site visits with a desk study of available documentary evidence. Consultations were held with the Environment Agency, Natural England, Shrewsbury and Atcham Borough Council, the Maltings Development Company and various other third parties in order to provide a clear picture of the site’s history and environmental setting.


The desk study work enabled ESI to develop an initial conceptual site model and to identify potential contaminant sources. These included a former gas holder, rail sidings, dye house, coal store and several fuel and chemical stores. A qualitative risk assessment identified key pollutant linkages associated with controlled waters, including the major Sherwood Sandstone aquifer and a local tributary of the River Severn, and also with the intended occupants of the site following its regeneration.


Informed by the initial conceptual site model, ESI conducted an intrusive site investigation across the area, combining trial pitting, hand digging and window sampling equipment. The laboratory sample results were critically examined in the context of the prevailing conceptual site model in order to clarify the likely source terms and allow meaningful site zoning. The subsequent risk assessment confirmed the presence of contaminant hotspots, which were typically linked with former land uses, and identified the need for additional targeted site investigations.


We take great pleasure in being able to carry out a contaminated land assessment that has supported the redevelopment of this site of significant industrial heritage, and one that is right on our doorstep.