Standards for Hydrographic Surveys

Preface

These standards are based on the latest edition of IHO Special Publication No. 44 (S-44), and on the previous standards versions of the Canadian Hydrographic Service (CHS).

It shall be noted that the issue of a new standard does not invalidate charts and nautical publications based on previous standards, but rather sets the standards for future data collection to respond better to user needs. Regions are encouraged to develop estimates of the positional and depth accuracies of hydrographic surveys conducted prior to the implementation of these new standards.

The principal aim of these standards is to specify requirements for hydrographic surveys in order that hydrographic data collected according to these standards is sufficiently accurate. An additional aim of the standard is to ensure that the spatial uncertainty of data is adequately quantified.

Previous versions of CHS Survey Standing Order (SSO) concentrated primarily on specifying accuracies for hydrographic surveys for the compilation of nautical charts. These standards do not include procedures that are included in other related documents. These standards must be used in conjunction with the Hydrographic Survey Management Guidelines, the ISO quality system process documentation, and the data coding guides. These standards will help Hydrographers and contractors to meet CHS survey precision and quality requirements.

Prepared by:
Canadian Hydrographic Service
Fisheries and Oceans Canada
February 2021
Edition 4

Table of Contents

• Introduction
• 1 Classification of Bathymetry
  • 1.1 Exclusive Order
  • 1.2 Special Order
  • 1.3 Order 1
  • 1.4 Order 2
  • 1.5 Order 3
  • 1.6 Imprecise order
  • 1.7 Order Classification
• 2 Position
  • 2.1 Introduction
  • 2.2 Horizontal Control
  • 2.3 Soundings
  • 2.4 Navigation Aids and other Features
• 3 Vertical Datum
  • 3.1 Sounding Datum
  • 3.2 Datum for Elevations
  • 3.3 Water Level Observations
• 4 Depth Measurement
  • 4.1 Introduction
  • 4.2 Sensor Calibration
    • 4.2.1 Multibeam Echo Sounding System (MBES)
    • 4.2.2 Multitransducer Vertical Sweep System (MTES)
    • 4.2.3 Single beam Vertical System (SBES) and multitransducers (MTES)
    • 4.2.4 Sound Velocity Profile Sensors
  • 4.3 Sound Speed Measurement
    • 4.3.1 Introduction
    • 4.3.2 Single Beam or Multitransducer System Survey
    • 4.3.3 Multibeam Survey
      • 4.3.3.1 Surface sound speed
    • 4.3.4 Oceanographic purposes
  • 4.4 Sounding Density
    • 4.4.1 Introduction
    • 4.4.2 Line Spacing
    • 4.4.3 Shoal Examination
    • 4.4.4 Depth Measurement over hazards
• 5 Various Other Measurements
  • 5.1 Aids to Navigation
  • 5.2 Elevations and clearances
  • 5.3 Bottom Sampling
  • 5.4 Natural coastline
  • 5.5 Current Observations
  • 5.6 Acoustic Backscatter
• 6 Data Processing
  • 6.1 Data Verification
  • 6.2 Data codification and presentation
• 7 Quality Control
  • 7.1 Introduction
  • 7.2 Positioning
  • 7.3 Depths
  • 7.4 Check Lines
  • 7.5 Sounding Density requirements
    • 7.5.1 Single-beam Echo Sounders (SBES)
    • 7.5.2 Side scan Sonar (SSS)
    • 7.5.3 Multibeam Echo sounders (MBES)
    • 7.5.4 Multitransducer systems (MTES)
    • 7.5.5 Airborne systems
• 8 Data Attribution
  • 8.1 General
  • 8.2 Point Data Attribution
  • 8.3 Depth Accuracy
  • 8.4 Geostatistics
  • 8.5 Error Sources and Budget
• 9 Data Management
  • 9.1 Data security and archiving
• 10 Reporting
  • 10.1 Reporting of Navigational Hazards