In 2016 Zambia needed precise flood prediction along the mighty Zambezi River basin, as well as analysis of the possibilities to construct dams along the river trail and improve water supply and water management in the country.
It was a great opportunity for Ofek’s international team to experience the positive impact of its activities on the well-being of river side communities in addition to facilitating the improvement of water management and use for the welfare of the country as a whole.
The project delivers two major outcomes:
1.Water management of one of the largest river basins in the world – The Zambezi River.
2.Creation of Flood hazard maps and Geo-Information database for the development of hydraulic models to predict floods and mitigate flood hazards.
As part of the 12,000 km2 project, our 3D division created a beautiful 3D model which shows a precise and detailed topographical information of the current state of the world renowned Landmark: The Victoria Falls.
Click on the picture below and enjoy an interactive 3D model of the Falls:
Victoria Falls: An Interactive 3D Modelling
To obtain the geographic information data required for the project, Ofek launched an aerial survey campaign with an airborne Lidar system and aerial mapping camera, producing an accurate topographic 3D model of the current state of the river basin, including high-resolution Orthophoto map.
The Government of Cyprus could, at last, breathe more easily. The country received financial assistance from the European Union, and in a controversial move, also from two major Cyprus banks, which it compelled to invest in the country. Thus, overnight, without being consulted or agreeing to it, major depositors in the two banks became its investors. Those investors, most of them seasoned businessmen, began to apply intense pressure on Government Ministries, because they only have one concern: “this investment must be worthwhile for us!”
Following the country’s financial breakdown, The Government of Cyprus tasked its various government branches with an urgent assignment: to find creative ways to significantly and rapidly increase government revenue.
The Cyprus Ministry of the Interior decided to assist this effort by providing the Government with the opportunity to increase Municipal Taxes collection. For this purpose there was a requirement to conduct a precise measurement of all areas and buildings on the island and to classify their use, which was not fully done before. The Ministry decided to create such a national database by means of high accuracy aerial photography survey, photogrammetric mapping and advanced LIDAR scans (use of aerial-borne pulsed laser to precisely measure ground ranges). Such precise mapping will enable to calculate and determine the amount of municipal taxes that could be levied on a total area of 6,200 square kilometers, containing about 500,000 buildings.
The Cyprus Government Office of Surveys published a tender to locate the most suitable company to implement the solution proposed by the Ministry. “Ofek Aerial Photography” won the tender and began to implement the project.
The Mission: Little piece of heaven to expose
Cyprus Here We Come
In order to map the entire island and respond to the requirements of the Ministry, it was necessary to create 3 different flight deliverables:
Vertical aerial photography (raw material for photogrammetric mapping) and generation of orthophotos (distortion-free vertical photography), and four-directional diagonal aerial photography (facilitating 3D measurement of every building on the island).
Mapping of buildings.
Production of DTM and DSM layers (height models of the topography and land cover, respectively.
The Geographical data was produced from two different flight types. The first type is implemented using a camera capable of scanning the area and providing the vertical and diagonal response, from 4 different aerial directions (a kind of beautiful interwoven photograph). The second type of flight is that of the LIDAR system that has the capability to cover the island with a cloud of laser points and to generate the layers of data required for the project.
The Airplanes results: Horizontal and LIDAR photographs
The flights planning stage had to take into consideration particulars such as, the location of the airfield, the location of regions with flight restrictions and locations with topographical fluctuations that affect the desired resolution. After approval of the flight plans from the Aviation Authorities of Cyprus, two Ofek aircrafts took off to Cyprus for the mission.
Problems Soon Appeared
Even at the planning stage a significant obstacle came to light: Greek Cyprus is separated from Turkish Cyprus, by a demilitarized, no-fly zone, under supervision of the United Nations. To obtain full area coverage it was necessary to fly in close proximity to the demilitarized zone. The Turkish authorities do not like the Greek Cypriots to photograph over the Turkish Cyprus borders, so much so that they might send up warplanes in response to such activity. Despite coordination of activities with the Cypriot Air Force, the United Nations and the Turks – there was concern regarding approaching this problematic area.
This is where Ofek’s A3 Camera System came to use. It was able to provide the appropriate solution to the problem. The A3 is an aerial photography system excelling in photography at great distances, far beyond the flight area. Thanks to the capabilities of the camera and ground measuring implemented close to the demilitarized zone, the coverage and mapping of the problematic and sensitive area was implemented in full.
Ortophoto from A3 camera
Cyprus is “On the Map”
500,000 buildings were exposed in their full glory in MultiVision, photogrammetric software developed by Ofek, capable of taking the diagonal photographs from four directions and present a 3D image that facilitates precise measurement – size of the roof, size of the garden, areas of covered patios, new “extensions” to buildings, building violations and more. It was now possible to begin to take decisions regarding the levying of municipal tax!
What’s the real size? Multivision gives the info!
As shown in the following video, here are DTM and DSM layers which create beautiful 3d modeling:
The author is Noam Schwartz, Manager of the Mapping Department at Ofek Aerial Photography