Historic Roman remains have been uncovered in Derby with the help of Groundforce’s Modular Aluminium Panel (MAP) lightweight box system. The system was used as trench support to provide a safe environment for archaeologists working to identify important Roman buildings and fortifications ahead of construction of the city’s new flood defences.
Derby is at risk of flooding from the River Derwent. Existing flood defences are nearing the end of their design life, and a severe flood could have a major impact on homes, businesses, infrastructure and important heritage assets in the city. For the last five years the Environment Agency and Derby City Council have been working on a plan to realign flood defences through the city centre to reduce the risk of flood damage, protect people, properties and strategic infrastructure, and also to regenerate key development sites along the riverside.
The £90 million project, known as “Our City Our River”, is being built in three phases, and is due to be completed in 2023. The first phase began last year [2015], with GBV – a joint venture between Galliford Try and Black & Veatch – winning an £11.7 million design-and-build contract for the first 3km of flood defences.
As part of the work GBV appointed Trent & Peak Archaeology to carry out archaeological investigations, to ensure that all sensitive areas within the project area were identified and mapped. GBV dug a series of trenches so that the archaeologists could get a better understanding of a Roman military camp and nearby settlements, known as Derventio.
“The work involved excavating known Roman remains such as ditches, roads and ramparts,” explains GBV Senior Engineer Edward Tonks. “They recorded and investigated the location of everything they found, as well as the building method, structure and age. In some areas the works also involved establishing the orientation of the features to enable sympathetic design for the flood defence scheme.”
Groundforce Shorco got involved because GBV was looking for a product or solution that would make the trench excavations safe while enabling the archaeologists to gather the information they required. That solution was the MAP box system, which provided the required support, but also allowed for the dig to be carried out progressively in layers, and gave the archaeologists a “window” in which to to view and record their findings.
Mr. Tonks says GBV considered various other options, including sheet piles and stepping the excavation, but no other option would give the necessary versatility or satisfy the archaeologists’ requirements. He says the solution has been 100% successful: “It achieved the goal which we set out to do; and I would have no hesitation to use the system again on future work.”