Draft Survey (Agency)

A draft survey is a scientific method for determining the quantity of cargo loaded or discharged from a bulk carrier by measuring the vessel's change in displacement. It is the primary method used globally for measuring cargo quantities in bulk trades — grain, coal, iron ore, fertiliser, clinker, and similar commodities — where belt weighers or static weighbridges are unavailable or impractical. At Unified Maritime Services, our agency draft survey team provides this service as a standalone commercial offering, protecting our clients' financial interests at the moment when cargo is transferred between parties.

Why Draft Surveys Matter Commercially

In a bulk cargo trade, the shipped quantity determines the freight invoice, the cargo insurance value, and the basis for any shortage claim. If the draft survey at loading shows 50,000 MT shipped and the draft survey at discharge shows only 49,500 MT received, someone is responsible for that 500 MT — and the dispute between the shipowner, charterer, shipper, and receiver can run into hundreds of thousands of dollars. A draft survey conducted by a qualified, independent surveyor with rigorous methodology provides the benchmark that all parties accept. Our surveyors follow the IMO/BIMCO draft survey guidelines and use calibrated instruments and approved stability calculation software.

The Draft Survey Process

A draft survey begins before cargo operations start. Our surveyor boards the vessel, takes preliminary draft readings at six positions (forward, midship, and aft on both port and starboard sides), measures the density of the port water, assesses the vessel's trim and list, and establishes the vessel's Initial Condition by verifying all constants, ballast water quantities, and the weights of all consumables on board. After cargo operations are complete, the same measurements are taken again and the difference in displacement — adjusted for the change in ballast, freshwater, fuel, and other variables — gives the cargo weight to within an accuracy of approximately 0.5% of the total cargo weight.

Protecting Charterer Interests

Charterers hire our draft survey team to verify that the quantity of cargo they are paying freight on matches the quantity actually loaded. In many voyage charter parties, the freight is calculated on the Actual Quantity Loaded (AQL) — so an inflated Bill of Lading quantity would mean the charterer overpays. Our survey at loading provides an independent check against the loading terminal's weighbridge or shore meter readings. Where discrepancies exist, we issue a formal report that the charterer uses to dispute the Bill of Lading quantity before the vessel sails — preserving their right to freight adjustment.

Protecting Shipowner Interests

Shipowners use draft surveys to protect against shortage claims at discharge. If the cargo quantity received at the discharge port is less than the Bill of Lading quantity, the shipowner faces a potential cargo claim. Our discharge draft survey — conducted simultaneously with or immediately after completion of discharge — establishes the out-turn quantity independently. Where the out-turn matches the loading survey and the difference is attributable to measurement error at the loading terminal rather than actual cargo loss, our survey report is the documentary evidence the shipowner uses to defend the claim through their P&I Club.

Independent Tally & Joint Survey

Where draft survey alone is insufficient — for high-value cargoes or where the parties have agreed to joint independent surveys — we can additionally appoint independent tally clerks to count bags, bundles, or units during loading or discharge, and arrange joint survey attendance by both the shipowner's and charterer's representatives. Joint surveys where all parties sign the final report dramatically reduce the risk of subsequent disputes.