Ground control & engineering survey

Scope & options

Static/RTK GNSS, total stations and levelling solve different control and setting-out tasks within one engineering survey network.

A GCP supports aerial mapping; a benchmark controls elevation; a check point independently tests achieved accuracy.

Survey control is meaningful only with a stated datum, coordinate system, observation method and adjustment/closure evidence.

Explore 5 service variants

GNSS/DGPS control and CORS-supported positioning

Establish and verify survey reference points.

State reference frame and method; do not use DGPS as an unexplained accuracy claim.

Construction setting-out

Mark design positions and levels on site.

Requires approved design coordinates and agreed tolerances.

As-built verification

Measure constructed positions against the design.

Measurements are not automatic design or structural certification.

GPR and electromagnetic underground utility mapping

Locate buried utilities using specialist ground instruments and records.

Detection is condition-dependent; expose utilities only under a separate authorised verification scope.

Aerodrome obstacle survey, OLS and eTOD support

Measure terrain and obstacles for aviation assessment.

Follow aerodrome/AAI specifications; the survey does not grant a height clearance.

Useful to know

Terms, explained

GNSS / DGPS: Satellite positioning methods used to establish survey control, coordinates and levels.
Total station: An optical-electronic instrument measuring angles and distances for engineering survey and setting-out.
GCP: Ground Control Point: a visible surveyed mark used to control or check aerial mapping.

Can I request ground survey without a drone?

Yes. Ground-only scope remains ground-only; the brief will preserve that exclusion and use appropriate survey methods.

Do existing DGPS points need to be checked?

Yes. Their datum, condition, provenance and suitability must be checked before they are adopted as control.

Can utility mapping find every underground pipe?

Material, depth, congestion, ground conditions and records affect detection. The report should distinguish measured, interpreted and unverified utilities.

Does an obstacle survey approve my building height?

It provides measurements for assessment. The competent aviation authority decides any required height clearance.

Method & limitations

GNSS static/RTK/PPK, total station and levelling selected by task.

Document datum, benchmarks, network adjustment and instrument checks.

Use ground methods where aerial capture cannot meet access or detail requirements.