Our company

Our company

We are the geophysical sub-bottom specialists

Based in the Netherlands, a country that lives, works and is even built in the sea, we have an intense interaction with the marine environment. The question is not whether there is a need for gaining knowledge about coastal status and processes for national safety, economy and environmental purposes. The question is how to obtain the best quality and complete datasets in a cost efficient way.

Since 1986 we participate in this process and we may state this way of thinking and doing has grown into the genes of our company. We operate global for numerous companies such as harbors, research institutes, universities, dredging companies, surveying companies, etc. We have our own sub bottom software SILAS 2D & 3D and produce the Rheotunes, EBP subbottom profilers and winches etc.


Mission statement

Stema Systems mission is to contribute to the quality and efficiency of the hydrographic and geophysical survey community, working on high seas offshore to the smallest waters inshore, by supplying and implementing state of the art and innovative survey sensors, systems, concepts and survey support.


Geophysical, sub-bottom & fluid mud

Stema Systems has developed a market leading sub-bottom profiling methodology using a combination of uniquely designed equipment with in-house developed software, resulting in a system that can provide a host of sub-bottom analysis results catering to the clients specific needs.

Over the past 15 years this combination of hardware and software has enabled the unparalleled insight into the sea/river bottom saving the users vast amounts of expenditure by enabling preventative dredging and negating claims by ship owners by providing an accurate picture of the slip and density of the fluid mud in its harbors.

To accomplish this mission Stema Systems has set itself following tasks and goals:

  • An independent company focusing on long term stability and as such enabling to build and maintain long lasting relationships with clients.
  • Employ and keep employed experienced personnel in system design, manufacturing and most of all in survey and geology/geophysics. Increase skills by regular training. By doing so ensuring the best support by thorough system knowledge and long lasting personal relationships.
  • Search for the outperforming components in the industry to integrate in turn key survey systems by trading OEM products, integrating parts in Stema System products and when nothing is available inventing and building solutions ourselves or participate in development trajectories with partners.
  • Keep close to the day to day survey services and feel what they need out there: reliability and quick response on questions and problems. This is the feed-back needed for innovative solutions and systems.
  • Communicate on good survey practice, innovative systems and concepts via training, congresses and articles.


Geophysical Survey Services

Not only does Stema Systems supply complete survey and monitoring systems, it is also aware of the fact that every minute counts, which is why it has established a service department that is at the disposal of its clients to ensure a minimum of down time. We are able to do so by combining a wide range of replacement units as well as a very highly skilled team that is available to our clients to assist them in almost all aspects of their projects, from phone support to the dispatch of service agents to the project to ensure the maximization of efficiency. We even help out your pre-survey to determine the most efficient way to do you seismic survey (choice of equipement, data processing and reporting).



There are many systems that will allow a range of hydro-graphical surveys to be made, however where Stema Systems distinguishes itself from the rest is that we are in a position to create tailor made solutions that will best suit the application needed of the client, such as basic units for the monitoring of barge dredging to the complete water column analysis from surface to actual bottom.

This possible combination of various modules ensures that Stema Systems is able to provide the clients exactly what they need at the most efficient price point avoiding costly and inefficient investments in the equipment. Stema Systems will with the help of its experienced staff assemble the hydro-graphical analysis system that is best suited for the application, it is able to do so due to the wide range of manufacturing partners that have been working with Stema since 1986.



We at Stema Systems know that having the most accurate data at the hands of the projects is vital for the efficiency. Therefore we have developed a in-house positioning system that will enable the user to conduct surveys and other maritime analysis to the highest degree of accuracy, using the latest GNSS technology incorporated into a Stema unit that is unique in the market.

Stema Systems has seen these systems used in a number of applications, such as but not limited to multi-beam surveys, positioning of Wind turbine foundations, the co-development of a cable touch downs system to mention but a few.



Stema Systems having combined the equipment for water column and sub-bottom analysis is in a position to offer a complete range of systems that will enable its clients to conduct comprehensive surveys of the entire maritime environment, from harbor slip monitoring to placement of wind turbine foundations.

Taking on projects that are commissioned by the most disconcerting clients Stema Systems offers the complete range of surveying equipment and on occasion can also provide the staff for the implementation of the various environmental monitoring projects that its clients are conducting.


Safety & Quality

At Stema Systems all employees are well trained and educated. Our survey consultants; either hydrographer or geologist have BOSIET. Our company is awarded with ISO 9001 and acts accordingly. Member of the hydrographic Society & CEDA (central dredging association)
Click here to go to the Hydrographic society.
Click here to go to the CEDA.

Company history

Until 2011 Stema Systems was a business unit of Stema Survey Services BV, founded in 1986 as a specialized engineering company, operating world wide in the disciplines of hydro-graphic, geophysical and geodetic surveying. In the first years the dredging industry was the main focus. With complex questions on fluid mud problems and seismic surveys for soil investigations, the company started a research program to develop hands on solutions for these challenges. This resulted in the Silas geophysical and DensiTune muddensity systems.

With a rapidly increasing number of users it was decided in 2006 to form a separate business unit for the development, sales and support activities: Stema Systems. In this way the systems activities could be professionalized and several innovative ideas, originating from our vast survey experience, could be realized. In 2012 Stema Systems has become an independent company, focusing on hydrographic/geophysical systems development and integration. Having its own sales and rental with related services (training, installation support, offshore positioning support). In 2014 the new management has changed the focus to its core competence; geophysics; sub-bottom expertise. Not only with hardware but also on software and consulting. As per 2019 Stema lounged SILAS 3D depth of Burial.  The company is led by our managing director Mr. R. Fisher.


Opening hours

Stema is available from Monday – Friday during office hours from 08.30 – 18.00

Contact us by Email