Halcrow is taking a key role in delivering a multi million pound scheme to reduce the impacts of global climate change in the Eastern region.
The Ipswich FDMS has been developed in the context of a wider high-level policy framework for flood risk management in East Suffolk. This identified the works required to raise the standard of protection in central Ipswich to 1 in 300 (0.33% annual probability of flooding) in 100 years time. At present, the existing flood walls in Ipswich provide a 1 in 20 year standard of protection (5% annual probability of flooding) in some locations. The primary recommendation made was to construct a tidal barrier across the New Cut and defences tying into high ground either side of the Barrier, in order to reduce the risk of flooding of up to 2,300 properties within Ipswich.
Furthermore, Ipswich is part of the larger sub-region that received formal Government designation as a New Growth Point in 2006. The levels of growth proposed for Ipswich are substantial and rely in part on the delivery of the Ipswich FDMS.
The scheme has been divided into compartments to facilitate and fast track its delivery. The Ipswich FDMS tidal barrier will take the form of a rising radial gate at the mouth of the New Cut on the tidal River Orwell. The radial gate will be 9m high and 20m wide across the channel. When fully raised, it will stand approximately 7.5m above the mean low water mark. When not in use (i.e. in an opened position), the gate will lie flat against the bed of the river. Around the proposed barrier, the Ipswich FDMS also comprise a series of flood defences walls and structures which tie into high grounds.
The flood defence structures either side of the Tidal Barrier works (the East Bank and West Bank works) comprise a combination of brick clad reinforced concrete walls and brick clad sheetpiles and road raising and realignment in a port area.
Halcrow has been appointed by the Environment Agency, to provide overall project management, engineering design and Environmental Assessments services.
Innovations
The project was designed to the new Eurocode design standards which are becoming the de facto standard for civil works and will be replacing many of the British Standards within the next few years. The main standards used included Eurocode 2 for concrete design, Eurocode 3 for sheet pile design and Eurocode 7 for geotechnical design. Designing to the Eurocodes presented an additional challenge for the design team as the standards are still largely unknown and not universally used, though the experience gained on the Ipswich Scheme will be directly relevant to a vast array of future project work.
Benefits
The flood defence scheme will dramatically reduce the likelihood of flooding in Ipswich which will have a positive impact on the development of the city.
There are numerous regeneration benefits which will be derived from the works. The Flood Defence Scheme will allow for the redevelopment of the waterfront area. The regeneration of the area offers opportunities for the renovation, restoration or removal of derelict land and buildings.
Other potential benefits of the project will be high real estate and property investment returns, socio-economic regeneration for inner city communities, the development of new visitor markets environmental conservation, city and regional promotion as it is one of the largest regeneration projects in the East of England.
The opportunities arising from the proposed development will benefit communities within the neighbourhood and the wider area. This investment could prove to be an important catalyst for the regeneration of the wider area, providing a solid foundation for the sustainable growth and prosperity of the local economy and further afield.