The River Thames Scheme (Surrey and SW London) is the largest fluvial flood defence scheme currently under development in the UK. This complex, multi-discipline project embraces state-of-the-art technical approaches in providing 150 m3/s additional conveyance to 32km of the River Thames.
The River Thames Scheme will create a new flood channel to reduce the risk of flooding to 15,000 homes and 2,400 businesses. The extensive environmental engineering, planning, fluvial and groundwater modelling and monitoring has established baselines and biodiversity net gain improvements as part of a long-term sustainable outcome. Our solutions align policy advice and environmental strategy and are supported by the regulatory compliance bodies. The scheme reflects the need to adapt to climate change as flooding increases. It represents a transformational opportunity for new habitats and re-landscaped environments for local communities.
Extensive feasibility studies and planning/monitoring (including stakeholder engagement) enhances resilience, contributing to a vibrant local economy and maximising the social and environmental value of the river. Sustainability and natural capital considerations include 60 hectares of new public open space, 15km of pathways and 250 hectares of habitat. The 8km channel will be built in 2 sections and includes increasing the capacity of weirs on the River Thames by installing additional weir gates and fish passes as part of the environmental planning, protection and enhancement measures.
Binnies are delighted to have been Lead Consultant on this >£250m construction project over the last 7 years for the Environment Agency working under NEC3 PSC. We successfully delivered the feasibility study and appraisal, business case and outline design, gaining Environment Agency (EA) approval in line with policy implementation. HM Treasury approval has just been confirmed, allowing the FBC and planning phase of the project to proceed.
We developed the preferred Strategy to Outline Design stage to obtain approval in principle from statutory and regulatory consultees and landowners. This formed the basis of the Outline Business Case (OBC) to Defra.
We generated new sources of funding to compliment that previously available through our Natural Capital approach. Generating a sustainable low carbon solution was critical for this scheme to support the social value and enhance the ecology and biodiversity of the area for local communities.
Ecological and biodiversity surveys informed environmental baselines and control measures for groundwater quality and levels, surface water quality and levels and river flow and water quality as part of the monitoring of environmental indices. Ecological surveys of the lakes as well as wintering and breeding bird surveys were also carried out. These are essential to inform outline designs of the flood channel and to support the environmental impact assessments. They also form the baseline against which environmental enhancements are measured.
Our approach to managing environmental risk included a NetZero carbon commitment that aligns with our corporate environmental route map which is in response to the UN Sustainable Development Goals.
Modelling has included fluvial, groundwater, surface water and sediment transport. Our Green-Book compliant business case has recently been signed off at HM Treasury level, releasing substantial partnership funding. The integrated engineering and landscape design solutions embrace creation of valuable public realm and habitat creation areas, whilst managing arisings of substantial excavation to form the new channels through historic landfill sites. All of the (non-coastal) essential competencies and wider essential services have been delivered, including those of Principal Designer. As a flagship project, we have worked with the Environment Agency to deliver challenging carbon and sustainability targets.