GIS Services for the National Mapping of the State of Qatar (2016 – 2020)

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CLIENT: The Centre for Geographic Information Systems, Ministry of Municipality and Environment
LOCATION: Doha, State of Qatar

“The highly accurate and complete spatial data produced by the Gannett Fleming team , such as orthophotos, vector maps, and LiDAR-derived DEM, will enable decision-makers to consider topographic and man-made features for planning purposes, and empowers data modelers and engineers for development projects.”
— Mr. Manaf Al-Sada, Director of CGIS

CHALLENGE

The Ministry of Municipality & Environment (MME), under the Centre for Geographic Information Systems (CGIS), needs up-to-date digital maps for the entire country every three to five years. In order to complete this task, they needed aerial photographs, orthoimagery, vector data, satellite imagery, mobile mapping system, aerial LiDAR, digital elevation model (DEM), UAV and geoid model update.

SOLUTION

The Gannett Fleming* team provided project management and quality control for the acquisition and onsite production of the various photogrammetric mapping products for the State of Qatar (Qatar) for use by the MME and other government agencies. The team delivered the original scope of services in three phases – aerial mapping, HD-Mobile Mapping system, and LiDAR data collection.

Aerial mapping was created for Qatar in phase I. Imagery was acquired at a ground sampling distance (GSD) of 20 cm. After performing the aerial triangulation, various products were produced from this imagery, including color orthoimagery and new stereo-derived vector maps. In addition, high-resolution satellite images were acquired and processed to produce orthomosaic images.

Phase II covered the delivery of an HD-Mobile Mapping system, consisting of a mobile mapping vehicle with LiDAR sensors, cameras, and associated hardware and software. Extensive training to conduct topographical surveys using mobile mapping technology was provided to the survey team.

During phase III, the Gannett Fleming team collected aerial LiDAR data at a point density exceeding 6 points per m². The main deliverables from the LiDAR survey were a DEM with 5 cm vertical accuracy and a classified point cloud. This topographic dataset forms the basis for various mapping applications, most engineering designs, and hydrological engineering analysis.

In addition to the three phases, the team updated the geoid model, which is the basis for the orthometric height calculation, the primary measurement used by planners, engineers, and others to determine height above sea level. A new gravimetric geoid model for Qatar, Qatar Geoid 2020 (QG2020) was established using a gravity survey of 400 points throughout the country. With the updated QG2020, Qatar will be able to use Global Navigation Satellite System (GNSS) or GPS to determine orthometric heights accurately for at least 15 to 20 years.

“The newly created geoid model exceeds the accuracy standards internationally and will be sufficient for GNSS surveys into the next decades. The successful execution of this project enabled CGIS to retain Qatar’s place as a world leader in geospatial technologies and quality of national datasets.”
— Eng. Mohammed Al-Emadi, Project Manager, CGIS

The Gannett Fleming team also procured both fixed-wing and multi-rotor UAVs / drones to meet the needs of the Qatar team and provided training to CGIS staff.

*This contract was completed under the Gannett Fleming name, however Gannett Fleming’s geospatial technology division, GeoDecisions, completed the work.

KEY TECHNOLOGY

  • Aerial photography

  • Aerial triangulation

  • Orthophotos

  • Vector data

  • Satellite imagery

  • Aerial LiDAR

  • Digital elevation model (DEM)

  • Geoid model update

  • Unmanned aerial vehicles (UAV) / Drones

KEY RESULTS

  • New GIS tools improve storage, manipulation, and sharing of spatial data with decision-makers and others to analyze and interpret the data easily.

  • Aerial mapping data produces up-to-date digital aerial photographs, orthoimagery, vector data, satellite imagery, and associated mapping products.

  • Three new acquisitions of high resolution satellite images (30cm) collected over the urban areas of Qatar (an area of 3500 Sq. km.), provide orthomosaic images for change detection and planning applications.

  • Aerial LiDAR data delivers an up-to-date digital elevation model and a classified point cloud for various engineering and hydrological applications.

  • HD-Mobile Mapping system assists surveying teams to produce topographic surveys, map updates, and road asset collection.

  • UAV /drones collect imagery and create maps and ortho updates quickly and efficiently.

  • The new geoid model computes accurate orthometric heights by converting GNSS ellipsoidal heights measured in the field.

  • The tools and data developed under this project allow them to conduct a detailed analysis of Qatar's land uses and build models to develop future land-use scenarios.

  • 2,778 map sheets were created for this project area – 2,500 map sheets for urban areas of 1K (1:1,000 map scale and 1 km x 0.5 km) and 278 map sheets for rural areas of 10 K (1:10,000 and 10 km x 5 km).