Although largely superseded by multibeam sonar techniques, singlebeam bathymetric survey remains a valid survey methodology, used in a variety of environments.
This is particularly the case in shallow water environments where the time required to achieve 100% insonification with a multibeam sonar is excessive or beyond a client’s budget.
In many multi-sensor survey specifications, clients often require both multibeam and singlebeam survey disciplines to be conducted as part of quality assurance and data verification procedures.
We utilise Dual Frequency Singlebeam Echosounders, operating at both 200kHz & 38kHz frequencies, the benefit of which is that the dual frequency transducer is can be used in areas of high silt deposition where conventional single, high frequency units only record the top of the silt level.
By utilising both the high and low frequencies, the low frequency pulse can be configured to penetrate the silt layers and record a level on the harder sea floor beneath. This can be particularly beneficial to dredging companies and civil engineers, who need to ascertain seabed levels for marine construction works.
In addition to industry echosounders, which can be deployed on to any larger vessel, we also operate a remotely operated vessel or USV, the Z-Boat 1800HP system. Equipped with a dual frequency digital echosounder, which transmits echograms in real time to the operator ashore, the craft is useful in shallow water areas – particularly inland where it would not otherwise be possible to gain access to the watercourse, loch or reservoir.
The system provides an additional health and safety benefit when operating in environments too deep to safely wade across but too shallow to operate a traditional hulled craft, removing the need for personnel to enter the watercourse for any reason.
In addition, the system can be deployed via a bespoke cradle into confined spaces or areas of limited access to enable survey works to be completed in areas such as cofferdams, caissons, tunnels and underground reservoirs.
Singlebeam surveys benefit greatly from the addition of side-scan imagery between the lines of sounding to ensure that the seabed is fully insonified. This ensures that all significant features, and in particular any dangers to navigation, are located.
High quality survey planning, real time quality assurance and stringent post survey quality control assure appropriate survey standards are met. We adhere to nationally and internationally accepted hydrographic survey standards including the International Hydrographic Organisation S44 protocol.