Specialist hydrographic surveys

APEM offers extensive experience of hydrographic surveys for the water, power and regulatory industries across the UK and Europe, collecting data efficiently and cost effectively.

We use industry-grade echosounders and GNSS positioning equipment to capture and generate accurate geospatial hydrographic data for a variety of environmental applications and our specialist team has experience of conducting surveys on many different types of water bodies.

Bathymetric surveys


We have a range of bathymetric sensors available to 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. Using this data we can calculate drawdown curves to show storage against reservoir level.

Similarly, we have undertaken bathymetric surveys of rivers to map their depth. Our bathymetric surveys can be complemented with a land based topographic survey to capture any topography above the water line, providing comprehensive data coverage above and below water, whilst also 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 can 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.

Our hydrographic survey equipment

APEM also has a conductivity temperature and depth (CTD) profiler that collects continuous data profiles for speed of sound (SoS) throughout the water column. Using this data we can 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 can be 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.

If you have any queries, please contact Mark Jowett, remote sensing technical specialist.
Alternatively you can email us here. Or call 0161 442 8938.