Agri-Sense were contracted to conduct a 90 000 ha aerial survey and 3D modelling of the entire sugar belt for Belize. This was requested by the Sugar Research and Development Institute, as part of the EU funded. FWC BENEFICIARIES 2013 - LOT 1 EuropeAid/132633/C/SER/multi project.
The project team consisted of 5 specialists who worked on site. The Ground survey team placed all the ground control pre-marks (GCPs) on the ground preceding the Aerial Survey Team. The team performed well and achieved the daily target of over 65 GCPs per day. The team worked for a total of 23 days placing GCPs throughout the various blocks, 5 days measuring road levels, and 5 days remarking the GCPs that were washed away from the excessive rain. The aerial survey team used 2 x C1 Cumulus UAVs to survey the area and covered an average of 3900ha a day. The team spent 28 days surveying. A total of 106 000 ha was surveyed which included the overlapping of the areas and some additional re-flights needed due to bad weather conditions.
Due to the variability of the vegetation and crop canopy heights, additional time was needed on the post processing to ensure the results generated were a true likeness on the ground conditions. During the Quality control process several blocks were re processed to remove excess noise and height differences outside the tolerance. The final DTM accuracy is 2.73cm RMSE in comparison to the GCP, and the vertical precision of the GCPs is 2.7cm thus a total error of 5.4cm.
Agri-Sense Delivered:
Orthomosaic of the 106 000ha
DTM of the entire area including natural drainage lines.
1552 GCPs (138 water levels,582km roads)
Map and contours of the entire area.
Agri-Sense were contracted by Dangote industries limited to conduct an Aerial & topographical survey for their project in Brong Ahafo Region, Ghana
The aerial survey was conducted using a team of 2 pilots who achieved an average of 3 400 ha surveyed per day. The site was divided into 9 blocks (Blocks A through I) strategically positioned along the arterial roads for ease of access. The work commenced on the Western side (Block A) and progressed Eastwards.
Despite a few minor challenges with the site access, the field work went very well. The few delays experienced at the start of the project due to rain did not have a major impact on the timelines, the dedication shown by the team meant that the work was done very efficiently and with a high level of morale. The data processing yielded accurate results which allowed for the post processing to be done effectively. The final DTM accuracy is 2.26cm RMSE in comparison to the GCP, and the vertical precision of the GCPs is 2.0cm thus a total error of 4.26cm.
Agri-Sense provided:
Aerial Imagery orthomosaic
DTM and 0.5m Contours
GCPs (241, pre marks, 797 post survey check points)
Maps
Final survey report
Agri-Sense Completed a topographical survey for Savannah Commercial Irrigation and Smallholder Development Project (Upscaling the Sisili-Kulpawn Irrigation Project) with a gross total area of 36 180 ha. The data was used for detailed irrigation and drainage design for a Net 12 000 ha sugarcane estate.
Even with minor challenges regarding the dust on site, the field work was completed successfully. The teams on site were welcoming and easy to work with, their willingness to work late hours allowed us to achieve our target. The Data processing yielded accurate results. During the Quality control process several blocks were re processed to remove excess noise and height differences outside the tolerance. The final DTM accuracy is 1.14cm RMSE in comparison to the GCP, and the vertical precision of the GCPs is 3.7cm thus a total error of 4.84cm.
Agri-Sense provided:
Aerial Imagery orthomosaic
DTM, DSM and contours
482 GCPs,
Maps,
Final survey report
Agri-Sense Completed a topographical survey 21 887 ha for LASUCO Nigeria. Agrisense was contracted for the surveying and processing of detailed drone imagery.
The Ground survey Team was led by Goodluck Madhau with support from Nick Bradley. Site work commenced on the 5th and the team placed all the ground control pre-marks (GCPs) on the ground preceding the Aerial Survey Team. The team faced challenges with terrain and site access. This was primarily due to swamp areas in a large portion of the AOI. The team worked for a total of 22 days placing GCPs throughout the various blocks with 2 days measuring road and water levels.
The aerial survey team was led by Nick Bradley. The team arrived in Nigeria at the same time as the Ground survey Team. The aerial survey teams placed some the ground control pre-marks (GCPs) on the ground to assist the ground survey team to save time.
The team started the aerial survey on the afternoon of the 5th of Feb and used 1 x Phantom 4 Pro UAVs to survey the area and covered an average of 1 750ha a day. The team spent 12 days surveying, 1 afternoon was down time due to hazy weather from the Harmattan. A total of 23 523 ha was surveyed which included the overlapping of the areas and some additional re-flights needed.
Agri-Sense Delivered:
Orthomosaic on the entire AOI
DTM & Contours
GCPs (445 points were measured, 13 water levels and 80km of roads
Maps
Final Survey report
Agri-Sense was contracted to obtain the high-level accuracy topographical data, an airborne survey with Terrestrial Ground control points and benchmarks. The project was split into 2 phases, phase 1 was 10000ha situated closer to the Rufiji River, Phase 2 consisted of 13 000 ha and was situated adjacent to phase 1 but further inland from the Rufiji River.
The Ground survey Team was led by Mlungisi Ncube with support from Russell longhurst. The team faced challenges with site access. This was primarily due to dense bush with limited road access throughout the AOI. This was expected due to the previous experiences during phase 1. A 3- wheel motorbike was used from the start of the project which assisted the ground survey team to
get ahead of schedule. The team worked for a total of 12 days placing GCPs throughout the various blocks and measuring road and water levels. The team completed the Ground phase on the 20th September and drove back to Dar es Salaam on the 21st.
The aerial survey team was led by Nick Bradley with the support from Russell longhurst. The aerial survey team on the first 2 days assisted the ground team place some of the control pre-marks (GCPs) on the ground to save time. Due to the challenges experienced during Phase 1, an RTK drone was used to conduct all flights in phase 2. The use of an RTK drone allowed for the placement of less GCPs than would have been used with a GNSS drone. This assisted the ground control team to keep on target. Additionally, the RTK corrections that were sent to the drone reduced the “wiggle” between control points so hence the use of less points. The team started the aerial survey on the 9th of Sep and used 1 x Phantom 4 Pro RTK UAVs and a DJI RTK BASE2 to survey the area.
Agri-Sense Delivered:
Orthomosaic of the entire AOI (ph1&2)
DTM & contours of the entire AOI (ph1&2)
76 GCP, 52 check points, 15 Drone Base control points & 3 water levels
Maps
Final Survey Report
Agri-Sense was contracted to obtain accurate topographical data using airborne survey with Terrestrial ground control points and benchmarks. An area of 9 104 ha was surveyed.
The Ground survey Team provided by SGSE was led by Simon S Dibya with support from Emmanuel H John. The team commenced work placing the GCPs under the guidance of Agri-Sense on the 26th January and placed all the ground control pre-marks (GCPs) on the ground preceding the Aerial Survey Team. The team faced challenges with placing some points due to the local villagers, but adjustments were made to incorporate additional point instead. The team worked for a total of 7 days placing GCPs throughout the various blocks and 2 days measuring road and water levels.
The aerial survey team was led by Russell Longhurst. The team arrived in Nigeria on the 28th January. Agri-Sense were supplied with a vehicle by SGSE with a driver and security and motorbike escort. The aerial survey team arrived on the Saturday at 12pm and commenced survey at 2pm the same
day.
Agri-Sense Provided:
Orthomosaic of the entire AOI including the approach channel
DTM & Contours for the entire AOI including the approach channel
Maps
Final survey Report
Phase 2
Phase 2 of this project was to assist SGSE with a catchment analysis to determine the flow and velocity of the runoff water collected into the natural drains and how this would affect the proposed irrigation and estate layout. In addition where civil structures are planned to be constructed (reservoirs, pump stations and irrigation rooms), additional survey points were collected and added to the final DTM model. and finally, a physical and visual understanding of stream crossing along the primary Bulk Water Supply (BWS) route from the primary PS to the reservoir was assessed as part of the catchment analysis and culvert flows calculated to determine the effect on BWS pipeline.
Agri-Sense Delivered:
GIS files
Auto-Cad Files
Report and calculations
Maps