Lee Catchment Flood Risk Assessment and Management Study

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Topographical survey

Channel and structure cross sectional survey

The channel and structure cross section survey was carried out by Maltby Land Surveys Ltd. The survey commenced in February 2007 and was completed in June 2007. A map showing the locations of the surveyed channel and structure cross sections is available below.

Topographical survey locations map
Loaded on: 21/09/07 - Size: 280kb

The survey provided information on rivers and structures profile, including cross-sections of the river bed, the river banks and any structures in the river channel, such as bridges or weirs. This information was gathered at regular intervals along the rivers to enable the computer models of the River Lee and its tributaries to be constructed. The project team would like to thank you for your co-operation with the survey teams over the duration of the survey. We would also like to thank the Gresham Metropole Hotel, Cork and Cork Airport & Flying School for the provision of secure facilities for technical equipment to Maltby Land Surveys.

Cross-sections are not required in Cork Harbour as a detailed bathymetric survey of the area has already been carried out. This survey data has been used by our project partners, MarCon Computations International Ltd., to develop a computer model of Cork Harbour.

LiDAR Survey

LiDAR (Light Detection and Ranging) involves using an aeroplane with a special measuring device to provide detailed information on the shape and height of the ground. LiDAR data has been surveyed along the river channels and floodplains and around the perimeter of Cork Harbour for the Lee CFRAM Study. The data has been used to develop a high resolution Digital Terrain Model (DTM). The DTM is being used in a number of the project activities including the flood mapping of both the flood extents and flood hazards.

FLI-MAP 400

As part of our flood defence asset survey, a very high resolution LiDAR geometric survey of major flood defences in the catchment has been completed. The work was carried out by BKS Surveys Ltd using FLI-MAP 400 - a helicopter mounted laser scanner system. The laser scanners gather detailed ground point data with up to forty points gathered per square meter of ground area. The survey provides detailed information on the shape and height of major flood defences in the catchment. This data has been input to the Flood Defence Asset Database (FDAD) and used in the construction of the the hydraulic computer models.

Photos

Old bridge in The Gearagh

Inishcarra reservoir

3D view of the LiDAR DTM of the Owenboy River

DTM data of Inishcarra Reservoir (Infoterra 2006)

Key Activities

The key activities to the project are

Latest news

Final edition of Lee CFRAMS newsletter (more)

Consultation on the SEA Environmental Report (more)

Non-Technical Summary for SEA Environmental Report published(more)

Consultation on the draft Flood Risk Management Plan (more)

Consultation on Lee Predictive Floodmaps (more)