a large green and white ship in a body of water

Draft Survey in Spain for Ships and Cargo Operations

The Draft Survey is a technical procedure used to accurately determine the actual cargo on board a vessel by measuring drafts before and after loading or discharging operations. This service is commonly performed on bulk carriers and solid cargo vesselsenabling calculation of the vessel’s true displacement and weight variation based on hydrostatic principles and independent verification.

What Is a Draft Survey?

A Draft Survey consists of measuring the vessel’s draft at multiple points (forward, aft, and midship) to determine displacement. By applying official hydrostatic tables and corrections for water density, list, and trim, the exact quantity of cargo loaded or discharged is calculated.

It is an internationally recognized method in maritime trade.

a large cargo ship sitting in the water
a large cargo ship sitting in the water

Application in Port Operations

Draft Surveys are primarily used in:

  • Bulk carriers

  • Grain shipments

  • Minerals

  • Coal

  • Fertilizers

  • Solid bulk cargoes

Although mainly applied to merchant vessels, it may also be carried out on commercial units and specific cargo operations

a large cargo ship in a body of water
a large cargo ship in a body of water

Technical Methodology

The procedure includes:

  • Manual or electronic draft readings

  • Verification of the list and trim

  • Water density determination

  • Application of official hydrostatic data

  • Displacement and net weight calculation

Accuracy in measurement is essential to prevent commercial disputes.

Red ship hull with draft markings
Red ship hull with draft markings

Importance in International Maritime Trade

A Draft Survey allows:

  • Verification of actual cargo quantity

  • Prevention of contractual discrepancies

  • Reduction of financial risks

  • Resolution of disputes between the shipper and the receiver

  • Independent technical reporting

It is an essential service in global maritime logistics.

a large ship in the water
a large ship in the water

Draft Survey Technical Report

The report includes:

  • Recorded draft readings

  • Applied corrections

  • Hydrostatic calculations

  • Net cargo determination

  • Technical conclusion supported by data

This document may serve as contractual support and technical evidence in case of disputes

blue and white ship on sea under white clouds during daytime
blue and white ship on sea under white clouds during daytime

Technical Integrity and Professional Reliability

The involvement of a licensed naval architect or marine engineer ensures:

  • Precision in measurements

  • Correct application of hydrostatic principles

  • Independent technical assessment

  • Clear and defensible reporting

Objectivity is critical in large-scale cargo operations.

Large red cargo ship sailing on the water.
Large red cargo ship sailing on the water.