Free Zone Surveying
Planning and documentation for free zones. El-Eman Office provides surveying for economic zones.
Reference frame and coordinates in economic zones
Free zone surveying needs one coordinate system followed by every contractor and consultant, because the zone hosts many projects built in parallel. A network of fixed points tied to the national network is established, and the coordinates and reference levels are documented in a report given to all parties.
- Control point density should suit the zone's size and complexity.
- Protect the points from damage during construction and re-check them regularly.
- Use the same reference frame in maps, engineering drawings and designs.
Plot subdivision and infrastructure
Subdivision follows investor needs for factories, warehouses and offices. Some activities need long road frontage and others need more depth. The plot layout should give each investor direct access to roads and utilities, with setbacks and road widths that allow trucks and cranes to move.
- Prepare the master plan and define functional zones.
- Set out road axes and plot boundaries on site.
- Calculate cut and fill to level sites and reduce soil hauling.
- Coordinate utility routes to serve all plots and allow expansion.
Surface drainage and data management
Industrial and logistics areas have large paved surfaces that collect rainwater quickly. The design therefore needs accurate level maps to define surface drainage directions and avoid flooding. It also helps to keep a spatial database recording delivered plots, completed utilities and the state of each.
- Update maps after each construction phase instead of waiting until the end.
- Link plot data to allocation records and contracts.
- Carry out an as-built survey of utilities before and after backfilling.
Coordination between investors and the owning authority
Several parties use survey data in a free zone: the developer authority, investors, consultants and contractors. Define one official source for approved maps and update copies whenever anything changes. Documents should include a list of reference points with their coordinates and the date of their last check, and digital files should be delivered in formats that open in AutoCAD and GIS software.
- Adopt a fixed naming system for files and versions.
- Decide who may approve changes to the master plan.
- Check each plot boundary on site before handing it to the investor.
Frequently asked questions
Why must the coordinate system be unified across projects?
Different systems cause differences between maps, disrupt utility coordination and create costly clashes during construction. Unifying them makes data easier to merge.
Is satellite-based surveying alone enough?
It is enough for many tasks, but covered areas or places near tall structures may need a total station to complete measurements accurately.
When should utilities be surveyed as-built?
Preferably just before backfilling, to record their true position and depth. After backfilling they are hard to locate and may be damaged by later works.
