Shipbuilding and repair provided employment for thousands of people on the River Tyne. Now all that remains of this once thriving industry is a fascinating legacy for industrial archaeologists and hundreds of acres of prime waterfront land.
One such site is at North Shields which has been home to dry docks since the 18th century. The 13ha site was bought by the Smith's Dock Company in 1891 and rapidly became the largest ship repair yard in the world. It thrived until the middle of the 20th century, with new docks added during the 1920s and 1930s, the last – the largest dock on the Tyne – being built as late as 1953.
By the 1980s, however, the entire industry was in decline, and Smith's Dock was no exception. The yard closed in the early 1990s, and has been derelict ever since.
The site poses major challenges for the developer and its consultant Fairhurst. Among these are the dry dock structures themselves, three of which are to be filled in, the site's unusual topography, which currently consists of two distinct plateaus with a 15m height difference between them and the high levels of contamination left over from the industrial processes that went on in the yard.When the yard was closed, the dock gates were either removed or decommissioned – by cutting their cables or by lowering them into the river. As a result, the docks are partially flooded. Two of the largest docks are to be completely filled in, while another two will be used for basement car parking beneath two 11-storey apartment blocks. Only Dock 5 will be retained as public amenity space. With the gates lying on the bed of the Tyne, it looked as if it would be necessary to work within cofferdams. However, a survey revealed that at least two might be salvageable. "From the survey it seemed like a reasonable assumption that the gates could be lifted, but we left it up to the contractor and designed the works in case the gates couldn't be lifted," explains Fairhurst's project manager Ian Whitfield.
In fact, civils contractor Volker Stevin managed to lift the 230t-plus gates for Docks 4, 7 and 8. They have been repaired and are being used as shuttering to enable the contractor to build permanent concrete stop ends to the docks. A cofferdam will still be needed to build the wall at the end of Dock 6, while the remaining, smaller, docks will be sealed during piling for the new quay wall.
One of the biggest challenges is dealing with contaminated material on the site. Most of the docks have a layer of silt in them measuring anything from 0.5m to 1m in depth, and the Environment Agency is very keen that this silt does not get into the River Tyne. "The silts contain a lot of tributyltins, which were a constituent of anti-fouling paints," explains Whitfield.The project's license includes a condition that "silt screens" must be built across the middle of each dock. Closing the lock gates provides a seal on three of the docks, while a granular bund keeps the silt away from the water until the permanent dock walls are finished. The scheme design allows for the silts to remain insitu in Docks 7 and 8, which are to be filled in.
The 10,000m3 of silt in each of Docks 4 and 6 will have to be removed. "We will have to stabilise the silts insitu to give them some geotechnical properties so that they can be utilised elsewhere on the site," says Whitfield.
There are other contamination issues to be dealt with too. Dock 5 – which is to be refurbished and retained – had been compartmentalised into individual storage tanks. These will have to be removed very carefully and taken off site.
Other contaminants are largely confined to the location of old workshops. "We can use old Ordnance Survey maps to tell us what activities happened at what location on the site, so we know what contaminants we expect to find," says Whitfield. "But in other areas there is general demolition material from where the site was levelled and we expect to find additional contaminated material, including asbestos."
Balancing the cut and fill on site is a major challenge. As well as the vast quantities of material required to fill the docks, material is needed to raise the level of the river frontage by 1m to make sure the development is safe from future flooding.
Volker Stevin started work on the Smith's Dock site in August 2007, and is set to complete the civils programme – including new piled quay wall, site clean-up, roads and drainage – in 2009. The entire development of 1,220 homes will be completed in 2012.Profile: Making Places
The developer of Smith's Dock is Making Places, a joint venture between Cofton and Places for People.
The two firms have joined forces to buy and develop land for large scale and complex developments across the UK, allocating a £350M rolling fund for investment.
Cofton's role is to identify and purchase land, negotiate the planning process and provide the essential infrastructure. Places for People funds and builds the homes. It is known for its developments in the affordable and social housing sectors.
Smith's Dock is the JV's first project. It consists of 1,010 riverside apartments and 210 townhouses, of which all but 30 are for outright sale - a reflection of a desire to raise levels of home ownership in the area.
Project Smith's Dock, North Shields
Client Making Places
Civils contractor Volker Stevin
Contract value £15M
Contract period mid 2007-2009
Development completion 2012