Our hydrographic surveys are a sophisticated and versatile tool to accurately assess the bathymetry, sediments, ecology, hydrometry and other environmental properties of bodies of water.
APEM offer extensive experience of hydrographic surveys for the water, power and regulatory industries across the UK and Europe, collecting data efficiently and cost effectively on many types of water bodies.
Our industry-grade echosounders and GNSS positioning equipment capture and generate accurate geospatial hydrographic data for a variety of environmental applications.
Bathymetric surveys
Bathymetric sensors measure the bed of a water body to determine its size, shape and volume. These surveys are typically used to determine the volume of reservoirs, and the data we capture helps us calculate drawdown curves to show storage against reservoir level.
Similarly, we undertake bathymetric surveys of rivers to map their depth. Complemented by a land-based topographic survey to capture any topography above the water line, our surveys provide comprehensive data coverage above and below water, whilst adding control to the survey.
Geophysical/sediment profiling surveys
We have a dedicated sub-bottom profiling sensor for geophysical surveys to determine the sediment profile of a water body. Through this application we determine sediment accumulation to determine sedimentation in reservoirs and rivers.
Velocity profiling
Using an Acoustic Doppler Current Profiler (ADCP), we map and measure velocity profiles through the water column for hydrological assessment and hydraulic modelling. We use this technique to map both spatial velocity and velocity discharge via cross section sampling, typically in rivers.
Ecological surveys
Using our scientific-grade split system echo-sounding unit, we capture ecological data relating to the density of fish populations and the abundance of macrophytes.
APEM also has a conductivity temperature and depth (CTD) profiler that collects continuous data profiles for speed of sound (SoS) throughout the water column. This data helps us apply accurate compensation to remove any potential errors from the influence of SoS. SoS compensation can be applied in real time or during post processing.
Our hydrographic surveys are co-ordinated according to client specification and budget. We have a variety of positioning equipment, ranging from DGPS (< 1m accuracy) to RTK GNSS (< 10 mm) solutions to provide accurate geospatial referencing data.
We also have a variety of survey platforms available to provide versatile survey solutions for any waterbody. Our survey craft include a trailer-mounted hydrographic survey vessel with onboard power supply and a fleet of smaller rigid inflatable boats for deployment where access is difficult. Our survey equipment can be mounted on any of our survey craft.
We use a variety of proprietary SONAR analysis software packages to accurately process the survey data and generate outputs such as bathymetric maps and sediment depth maps. This data can be presented in a variety of ways, including digital terrain models, 2D contour maps and 3D wireframe models. The data can also be provided in formats compatible with GIS and CAD.
The team at APEM would be happy to answer any questions you have about hydrographic surveys. Please use the form below to get in touch.
