Open ProvincesNautical-chart discrepancy: report a correction to the Hydrographic Service
Identify the chart and edition, record the position and submit a hazard or correction to the official service.
Do not continue on a dangerous route to confirm the error. Use the latest official warnings, publications and navigation methods.
Check the edition
Record chart number, edition, last correction applied, paper or electronic format and device used. A private layer may be the source of the discrepancy.
Document the position
Record coordinates, datum, depth or object observed, time, tide, weather and positioning method. State your confidence level.
Submit the report
The Canadian Hydrographic Service asks mariners to report discovered hazards and needed corrections through its marine information form.
Update your copy carefully
Keep confirmation and consult Notices to Mariners. Alter an operational chart only through the official method and inform people using the same copy.
Update charts and report discrepancies — CHS
Sources and limits
Official sources are linked in the guide. Checked August 29, 2026; confirm current rules, forms and deadlines with the responsible authority.
General information based on federal and national rules; provincial rules may differ. Confirm with the official body before acting. Last reviewed : 2026-08-29.