CEFAS24-146 RFQ for Light Detection and Ranging (LiDAR) surveys at Sizewell.

Tender description

Request for quotation for Light Detection and Ranging (LiDAR) surveys at Sizewell. The BEEMS (British EDF Estuarine and Marine Studies) programme is funded by Sizewell C Limited. Through this programme, Cefas provide authoritative scientific information on the marine and transitional waters in the vicinity of potential new build nuclear power stations and require a competent supplier to deliver the element described below. Requirement: To support the delivery of the BEEMS Programme, Cefas have the requirement to work with a supplier to assess error margins around estimates of the ground elevation under dune and coastal vegetation at Sizewell-Minsmere. Accurate, or slightly conservative, estimates of the beach and dune surface under vegetation are required to ensure that beach volumes (specifically Soft Coastal Defence Feature (SCDF) volumes) are not over-estimated which could otherwise result in delayed SCDF maintenance triggers and maintenance, and increased risks of SCDF buffer & Hard Coastal Defence Feature (HCDF) exposure. The supplier is required to test the next generation of Light Detection and Ranging (LiDAR) sensors, which have more power and improved laser to penetrate further into the vegetation, against elevations from detailed ground truthing Global Navigation Satellite System (GNSS) and Red Green Blue (RGB) optical imagery. Surveys are required to be undertaken when coastal vegetation is at its minima, average and maxima (c. January, March/April and June). The proposed work will include three LiDAR surveys, each with accompanying ground truth surveys, collected with a GNSS receiver rover (short occupation only, no tripod required). Accuracy requirements for ground truthing measurements are to be within Root Mean Square Error (RMSE) ±3cm horizontal and ±4cm vertical, equivalent to a detailed survey performed under relative kinematic methodology as per RICS ‘Use of GNSS in land surveying and mapping 3rd edition’ standards. Please see supporting documents contained within the bidder pack for details of the survey area, and minimum expected ground truthing points. Each summary report will require the supplier to: • Extract the LiDAR Digital Terrain Model (DTM) elevation (if more than one model has been used then extract for each model), the LiDAR Digital Surface Model (DSM) point cloud mean and minimum elevations, and the RGB optical DSM elevation, at each ground truth location. o To be performed separately for calibration and validation data, and then performed all together. • Generate difference statistics for the ground truth validation points in the LiDAR DTM and compare with the LiDAR calibration points • Generate difference statistics and graphics for all methods against the ground truth values. • Draw conclusions about different methods and how well they estimate the true ground surface both in general and specifically for each broad vegetation type (low grass, dune vegetation, reeds, gorse, shrubs/trees). Express this in elevation and beach volume terms (Cefas will provide the method for the latter) • Present the results for Cefas in advance of a short report on all of the above. Survey Environment: The surveys will take place in a challenging environment: the airspace is restricted; coastal launch sites are exposed to highly variable wind conditions requiring flexible and reactive flight planning to carry out flights safely; notification and security procedures are rigorous; and sensitivities arise from undertaking flights in statutory nature conservation areas and in close proximity to Sizewell A, Sizewell B and the Sizewell C construction site. For these reasons, Cefas requires a highly experienced supplier to ensure that operations are conducted safely and in compliance with all the procedures required by the Civil Aviation Authority, The Office for Nuclear Regulation, Sizewell C Ltd and other Power Station Operators in the location. The use of tilt corrected survey equipment is encouraged for ground measurements to enable measurements within gorse bushes. A topographic shoe (flat shoe) is essential for the survey pole due to the softness of the substrate causing the normal spiked tip to penetrate the sand/gravel. Health and Safety: Cefas requires the following Health and Safety Training for field staff to be in place ready for the first survey: 1 x staff with a valid First Aid at Work certification 1 x staff with Emergency First Aid (separate to the individual holding the First Aid at Work certificate) All staff to maintain manual handling certification All staff to hold risk assessment training 1 x staff with a valid driver’s licence or enhanced certificate for off-road vehicles (depending on method of travel on site). All remote pilots to hold A2CofC (Certificate of Competence) and GVC (General VLOS (Visual Line of Sight) Certificate) A Risk Assessment and Method Statement (RAMS) will also be required to be produced prior to survey mobilisation. These RAMS will be approved by Sizewell C prior to mobilisation. Cefas will facilitate this process and approval if necessary. Deliverables: 1. One survey to be undertaken January/February 2025. a. A draft report to be issued six weeks following successful survey, including data analysis. b. Survey data to be provided alongside report, including a copy of raw ground truth and calibration GNSS measurements, raw LiDAR data, and processed LiDAR DTM. Data to be transferred via secure Azure Cloud Storage. Coordinate reference system to be British National Grid + ODN (EPSG:7405). 2. One survey to be undertaken March/April 2025. a. A draft report to be issued six weeks following successful survey, including data analysis. b. Survey data to be provided alongside report, including a copy of raw ground truth and calibration GNSS measurements, raw LiDAR data, and processed LiDAR DTM. Data to be transferred via Azure Cloud Storage. Coordinate reference system to be British National Grid + ODN (EPSG:7405). 3. One survey to be undertaken June 2025. a. A draft report to be issued six weeks following successful survey, including data analysis. b. Survey data to be provided alongside report, including a copy of raw ground truth and calibration GNSS measurements, raw LiDAR data, and processed LiDAR DTM. Data to be transferred via Azure Cloud Storage. Coordinate reference system to be British National Grid + ODN (EPSG:7405). 4. Collaborative Project Team Meeting outlining preliminary results. Prior to drafting the final report, the analytical methods for processing LiDAR data, results on comparisons between the methods and conclusions about the efficacy of LiDAR should be presented to Cefas. Discussions and feedback should then be accounted for in the final project report. The presentation should be made online over Teams. 5. Final project report. a. A final technical report to be delivered to Cefas by 15 August 2025, including results of each survey completed for this contract. Quantity: Three surveys, three draft survey reports and one final project report. Location for services to be undertaken: Sizewell, Suffolk. Please refer to the bidder pack supporting documents for exact area of interest.