Store Street, Manchester Watching Brief Planning Ref. 126608/FO/2020 Author(s): Joe Turner BA MSc PCIfA Written Scheme of Investigation December 2020 Store Street, Manchester – Archaeological Watching Brief 1. Introduction This Written Scheme of Investigation (WSI) has been produced by CFA Archaeology on behalf of H20 Urban (NO.2) LLP to detail a programme of archaeological monitoring to be undertaken at Store Street, Manchester during relevant construction work. The scheme comprises the construction of a high-rise residential development which will utilise a piling method and phased levelling of the site. The archaeological watching brief is required per Condition 7 of the approve planning application (126608/FO/2020): ‘No demolition or development shall take place until the applicant or their agents or successors in title has secured the implementation of a programme of archaeological works. The works are to be undertaken in accordance with a Written Scheme of Investigation (WSI) submitted to and approved in writing by Manchester Planning Authority. The WSI shall cover the following: 1. A phased programme and methodology of investigation and recording to include:- an archaeological watching brief 2. A programme for post investigation assessment to include: - production of a final report on the investigation results 3. Deposition of the final report with the Greater Manchester Historic Environment Record. 4. Dissemination of the results of the archaeological investigations commensurate with their significance. 5. Provision for archive deposition of the report and records of the site investigation. 6. Nomination of a competent person or persons/organisation to undertake the works set out within the approved WSI. In accordance with NPPF Section 16, Paragraph 199 - To record and advance understanding of heritage assets impacted on by the development and to make information about the archaeological heritage interest publicly accessible GMAAS will monitor the implementation of the recording on behalf of Manchester City Council’. This WSI provides the detailed method statement for an archaeological watching brief, and; should archaeological remains be encountered. The watching brief will be maintained primarily during the levelling of the site. Levelling on the site will be undertaken in a phased programme which comprises initial levelling/infilling required to produce a level surface for high level piling; this will then be followed by reduction in ground level for mid-level piling and subsequently lower level piling following further ground reduction. Full details of the construction scheme will be provided within the site contractors method statement prior to STOR2/WSI 1 CFA commencement of on-site works. It is not considered necessary for archaeological monitoring to be undertaken during the piling works. 2. Site Location and Description The site is located on the south side of Store Street, which is on the east side of Manchester City Centre, centred on National Grid Reference SJ 85064 98128 (Fig.1). The proposed development site is comprised of a roughly triangular plot of land, bounded by Store Street on its north-west and Ashton Canal on its south west. The north-east side of the site is bounded by a large stone wall, beyond which is Millbank Street, leading from Store Street, and residential development along the Ashton Canal tow path. To the west of the site is the Store Street Aqueduct which carries the Ashton Canal across Store Street and is a Grade II* listed building (1270666). The bedrock geology across the proposed development area site comprises Chester Formation (sandstone), a sedimentary bedrock formed approximately 247 to 250 million years ago in the Triassic Period, in a local environment previously dominated by rivers. Also recorded are superficial deposits of Till, Devensian (Diamicton), deposits formed up to 2 million years ago in the Quaternary Period in a local environment previously dominated by ice age conditions (BGS 2020). 3. Archaeological and Historic Background The following derives from the archaeological desk-based assessment (CFA Archaeology 2020): The Ashton Canal built at the end of the 18th century forms the south-west boundary of the proposed development site. Work on the canal began in late 1792, constructed in a traditional narrow lock style, and stone line, mostly with gritstone, quarried locally around the Ashton and Stalybridge areas. Most of the construction had been completed by 1795, with some traffic moving along parts of the canal by this time although later improvements and additional construction were made after this date, including the locks around Ducie Street and the Store Street Aqueduct (1270666) which is located immediately to the west of the proposed development site. Expansion of the canal continued into the mid-19th century (Keaveney & Brown 1974, 4-8). The Store Street Aqueduct (1270666) is a Grade II* listed building, construction of which began in 1794, and was completed in 1799. The aqueduct crosses Store Street at an angle of 41 degrees, although when built it carried the Ashton Canal across the Shooters Brook valley as Store Street was yet to be laid out. The aqueduct is constructed with ashlar stone with angled piers in a style of early pack horse bridges, and measures approximately 70m in length. It is thought to be one of the earliest surviving examples of a canal aqueduct with a skewed arch. When Store Street was later constructed, the Shooters Brook was diverted beneath the road (Historic England 2020; McNeil & Nevell 2000). Store Street appears to have been planned by the early 19th century and canal wharfs were constructed to the east of the site by the mid-19th century. In the late 19th century and into the 20th century the proposed development site was occupied by several light industries and warehouses, and the demolished remains of these buildings are likely still present within the site, although no basements are recorded on the Goad Insurance plans. STOR2/WSI 2 CFA Prior to the construction of Store Street, Shooters Brook appears to have run through the proposed development site, as identified on the 1807 Roper map. It is possible therefore that palaeochannel remains of Shooters Brook may be located within the proposed development site and may be exposed during development. 4. Project Aims The desk-based assessment identified that there is potential to identify archaeological features relating the construction of the Grade II* listed Store Street Aqueduct (1270666); former demolished buildings and possibly the remains of the former Shooters Brook, depending on the depths of site levelling. The general aim of the watching brief is to determine the location, extent, date, character, condition, significance and quality of any archaeological remains liable to be threatened by the development, should they exist on the site. 5. Archaeological Methods Watching Brief CFA Archaeology is a registered organisation with the Chartered Institute for Archaeologists (CIfA). Work will be conducted with regard to the Institute’s Standards documents (CIfA 2014a-c), relevant Historic England guidance documents and this WSI. Recording of all elements will be done following established CFA procedures. The details of the proposed groundworks and levelling will be outlined within the contractor’s method statement prior to the commencement of construction works. It is anticipated that archaeological monitoring will only be required during phases of ground reduction. The site levelling will be monitored by a qualified archaeologist to the top of any archaeological features or deposits or to any required reduced levels in order to best facilitate the recording of any possible surviving features. Any other groundwork associated with the development will be monitored by a qualified archaeologist. Any further excavation required to fulfil the objectives of the watching brief will be carried out by hand. Samples of all features of archaeological interest will be excavated in order to establish their likely date, nature, extent and condition. All such sample excavation will be conducted by hand. All excavation and on-site recording will be carried out according to standard CFA procedures, principally by drawing, by photography and by completing standard CFA record forms. The stratification will be recorded even if no deposits of archaeological significance are discovered. The location of the ground works will be recorded using industry standard surveying equipment and tied to the National Grid. Vertical survey control will be tied to the Ordnance Survey Datum. Sections will be recorded by means of a measured drawing at an appropriate scale. Sections will normally be drawn at 1:10. The height of a datum on the drawing will be calculated and recorded. The locations of sections will be recorded on the site plans, relative to the site grid. STOR2/WSI 3 CFA Cut features will be recorded in profile, planned at an appropriate scale and their location accurately identified on the appropriate plan. Photographs will include an appropriate scale and where necessary a north arrow. All photographs will be recorded on a photographic register detailing subject, location and direction of shot. Any human remains encountered will be reported to the appropriate authorities and left in situ. If removal is necessary this will comply with the relevant Government, licence, regulations and guidance. All artefacts, including faunal remains, will be retained for analysis. Post-excavation storage requirements