2013 Alberta Flood Recovery – Bathymetric Pier Scour Survey

With total damage estimates exceeding $5B, Alberta’s 2013 catastrophic flooding is said to be the costliest disaster in Canadian history.

MMM Group Limited conducted bathymetric pier scour survey inspections to identify any scour-related flood damage and related risks to Southern Alberta’s bridges, in order to ensure an appropriate level of safety for travelling Albertans.

A total of 34 sites were identified for inspection within an accelerated three-week program.

  • The use of a portable high-frequency echo sounder (shallow draft ZEBEC craft and 8 hp engine, equipped with a single beam echo sounder utilizing the 235 kHz frequency) for bathymetric data acquisition was ideal for the shallow waters encountered.
  • A Leica dual frequency GPS receiver with a robotic total station set-up on the shore assisted in accurate positioning beneath the superstructure of the bridges.
  • Streamlined post processing of data, as well as effectively combined position and sounding data were the result of the direct integration of the echo sounder and Leica survey instruments.
  • For every bridge site, MMM provided three dimensional geodetic coordinates for the river bottom, deck elevations above existing piers (to allow for comparison with previous data sets), and a survey datum report.

Roles:

  • bathymetric survey and real-time positioning
  • data collection and interpretation
  • pier scour inspection