QT MIỀN BẮC
Topographic Survey
Topographic mapping at scales from 1:500 to 1:5,000 for feasibility studies, basic and detailed design, and site-grading volume calculation. The survey method is chosen by site area, land cover and required accuracy.
Choosing the method
| Site conditions | Method | Notes |
|---|---|---|
| < 5 ha, urban, dense features | GNSS RTK + total station | Point-by-point detail survey |
| 5–500 ha, open terrain | UAV photogrammetry + GCPs | Fast, orthophoto included |
| Forest, dense shrub, linear corridors | UAV LiDAR | Ground points beneath canopy |
| Reservoirs, rivers | Combined with echo-sounder bathymetry [x if available] |
Deliverables
- Topographic map in DWG/DGN, VN-2000 datum on the local central meridian, national height datum.
- DEM/DTM (GeoTIFF), contour lines, TIN.
- Longitudinal and cross-sections, cut-and-fill volume tables.
- Field books, technical report, control network results.
- WebGIS link with base map and orthophoto.
Workflow
- Collect existing data and reference horizontal/vertical control; prepare the technical plan.
- Establish the control network (static/RTK GNSS, differential levelling).
- Detail survey / photogrammetric flight / LiDAR flight as planned.
- Processing and cartographic editing to Vietnamese topographic symbology; accuracy check on independent checkpoints.
- Acceptance and delivery.
Technical standards
- Circular 68/2015/TT-BTNMT – direct topographic surveying at 1:500–1:5,000.
- TCVN 9398:2012 – Surveying works in construction.
FAQ
- What do you need for a quotation? Site boundary (KML/DWG/georeferenced image), map scale, contour interval and intended use.
- How long does it take? [x] days for a 10 ha site by UAV, depending on weather and flight-permit lead time.