Science Center Objects

Bathymetric surveys allow us to measure the depth of a water body as well as map the underwater features of a water body.  Multiple methods can be used for bathymetric surveys including multi-beam and single-beam surveys, ADCPs, sub-bottom profilers, and the Ecomapper Autonomous Underwater Vehicle. We use bathymetric surveys for many different types of research including flood inundation, contour of streams and reservoirs, leakage, scour and stabilization, water-quality studies, dam removal, biological and spill, and storage and fill in reservoirs and ponds.

Bathymetric surveys allow us to measure the depth of a water body as well as map the underwater features of a water body. 

Multiple methods can be used for bathymetric surveys: 

Visualization of single-beam bathymetry
  • Multi-beam surveying: A multibeam echo sounder attached to a boat sends out a wide array of beams across a "swath" of the waterbody floor. As the beams are bounced back from the waterbody floor,  the data is collected and processed. The processed data can be viewed in real time on the boat during the survey. Multi-beam surveying is generally done in larger water bodies.
  • Single-beam surveying: Rather than sending out a wide set of beams, single-beam bathymetry measures the water depth directly under the boat. Single-beam surveys are generally used for smaller water bodies.
  • Acoustic Doppler Current Profiler (ADCP): ADCPs are used throughout USGS to measure streamflow. ADCPs measure water velocity by transmitting sound waves which are reflected off sediment and other materials in the water. Data collected from ADCPs can then be used to for bathymetric mapping.
  • Sub-bottom profilers: Sub-bottom profilers are most commonly used to view the layers of sediment and rocks under the water body floor. A transducer sends a sound wave to the water body floor. This sound wave can penetrate the water body floor. The data returned from the sound waves can be mapped to show the layers beneath the water body floor.
  • Ecomapper Autonomous Underwater Vehicle: The Ecomapper can collect detailed bathymetric data, down to one-foot contours, in places that are difficult to reach with boats. The Ecomapper uses side-scan sonar and a Doppler velocity log.

 

We use bathymetric surveys for many different types of research:

Example of river bathymetry
  • flood inundation
  • contour of streams and reservoirs
  • leakage
  • scour and stabilization
  • water-quality studies
  • dam removal
  • biological and spill
  • storage and fill in reservoirs and ponds

 

 

 

Current Partners for Multibeam Surveys

  • Citizens Energy Group (Morse and Geist Reservoirs)
  • USGS Illinois Water Science Center [in cooperation with the U.S. Army Corps of Engineers] (Lake Michigan shore front near near Burns Harbor, Des Plaines River in Joliet, IL)