New 3D model to help mitigate groundwater flooding

Groundwater flooding is the emergence of groundwater at the surface, which can occur in a variety of geological settings, including areas with historical mining. In England and Wales, it’s estimated that groundwater flooding accounts for an estimated £530 million in damages per year.

Project Groundwater Northumbria aims to increase awareness and understanding of groundwater flooding and help prepare for and mitigate flood events through innovative approaches and technologies. The project, in which BGS is a partner, is led by Gateshead Council and is part of the Environment Agency’s Flood and Coastal Resilience Innovation Programme.

Following a major groundwater flood event in Gateshead in 2016, along with several smaller incidents, BGS has constructed a subsurface map and produced a free, 3D geological model of the bedrock in Gateshead. These help better understand the sequences and geometries of the shallower soil layers (superficial deposits) at tens of metres of depth, alongside structures and boundaries in the bedrock to several hundred metres of depth.

The north-east of England was a major centre for coal mining. In areas with historical mining activities like Gateshead, the effect of mine workings on groundwater movement can be significant. The map and model will give a better understanding of how the natural subsurface conditions, combined with the legacy of human activity in the subsurface such as abandoned coal mines, affects the direction of groundwater flow.

The insight provided from the anticipated groundwater flow paths will help identify where groundwater flooding is likely to occur. This will allow Gateshead Council (and other organisations, such as the Environment Agency and Northumbrian Water) to better deploy resources more effectively and monitor the speed and spread of flooding in real time, to help manage and alleviate groundwater flooding in the area.

The 3D geological model of Gateshead, released as part of Project Groundwater Northumbria, will help us to understand the impact of groundwater movement in this area and improve Gateshead Council’s response to future floods.

The model is an innovative step forward in how we capture data. Traditional geological maps don’t allow to us to show the interaction of mine water and groundwater, but we can showcase them with this model. It has really helped us to improve our 3D understanding of coal fields and how water flows through them. In turn, this is part of a wider programme of 3D urban geology across the country.

Project Groundwater Northumbria showcases how multiple organisations can work together on one project with the same aim and highlights the geological and technologies advances that can be achieved.

Ricky Terrington, BGS 3D Geospatial Lead and project leader.

The 3D geology model for Gateshead can now be accessed for free on BGS’s Onshore GeoIndex viewer.

The reports produced as part of this project are available to read:

• Superficial hydrogeological domains for the Gateshead area — Project Groundwater Northumbria
• Bedrock sandstone channel subsurface mapping for the Gateshead area — Project Groundwater Northumbria
• 3D geological model report of the bedrock geology underlying the Gateshead area — Project Groundwater Northumbria
• Project Groundwater Northumbria (FCRIP) — phase 1 geological cross-sections