Salt Water Surface Water Monitoring

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Developing a harmful algae monitoring service for aquaculture

The damage caused by harmful algae is a recurring problem for the global aquaculture sector with large financial impact. Insurance company Swiss RE estimates that harmful algae cause damages of (on the average) €65 million euro per year for insured salmon farm companies. Total damages to salmon aquaculture by extrapolation amount to the sixfold or €380 million. Other (non-quantified) market opportunities exist as a result of damages to shellfish- and shrimp aquaculture. Scientists in the field expect that the incidence of Harmful Algae will increase globally as a result of the combination of various factors: global warming, intensified rainfall leading to increasing nutrient run off, intensive agriculture run off, and the spread of exotic species of algae by (untreated) ship ballast water.

Our service offering consists of monitoring surface water quality and specifically harmful algae at professionally run farms cultivating salmon, other fish, shellfish and shrimps. The possibility to record and prevent part of damages by timely monitoring creates the demand for our services, not only with farms, but also indirectly with other stakeholders such as aquaculture insurance companies.

Feasibility study

Our feasibility study took place at Marine Harvest Canada, based on Vancouver Island, part of the world’s largest salmon production company, with other salmon production facilities in Chile, Ireland, Scotland, the Faroe Islands and its head office and main production in Norway, and a total production value of 2 billion €. The production sites on Vancouver Island are often subject to substantial damage from several species of harmful algae. For example, in October 2014 damages at Marine Harvest Canada alone amounted to 7 million c$.

The current method of surface water quality monitoring consists of sampling a large number of stations at various levels of depth and consequent microscopy analysis, in combination with sampling of other environmental parameters. This offers insufficient information on the spatial distribution of the threat.  As a result of the complexity of the system it has not lead to knowledge of the causal pathway of algae development, despite the fact that the companies already have more than 20 year of experience in dealing with this phenomenon.

Aquaculture companies have developed various capital and labor intensive tools and strategies for preventing harmful algae from coming into contact with the fish. These consist of lowering tarps to create a barrier between the water in and outside the cages, increasing distribution of compressed air from manifolds under the fish cages, and by stopping to feed the fish, which reduces among others the digestive and consequent respiratory activity of the fish, and makes them go the larger depths of the cages. With production management there is a strongly felt need for improved early warning systems for the occurrence of specific species of algae, in order to effectively apply and improve mitigation methods, as well as their timing.

As result from the feasibility study we were able to demonstrate the usefulness of Earth Observation data archives by preparing movies based on gap-filled MODIS chlorophyll-a and sea surface temperature images. These movies were very illustrative for the local and wider area dynamics of algae development. Furthermore, close collaboration in analyzing cell counts of specific species of algae, spectral observations by the user (using the WISP-3 spectrometer) and satellite image processing led to the successful development of algorithms and indicators for specific algae species suitable for among others MODIS and MERIS images. The MODIS results helped to understand in hindsight the development of an algae bloom that left a damage of over 0,5 MEuro. This is considered a very useful near real time (NRT) monitoring service product.  

The objective of this Feasibility Study is the establishment of a sustainable service for improved monitoring and alerting of water quality anomalies for aquaculture.

 The feasibility study aims at exploring the possibilities to offer relevant services to the market place for ecological surface water quality monitoring. The indicated services combine the data interpretation of satellite imaging and local in situ monitoring. 

Users and their needs

The prime target users are aquaculture companies and aquaculture insurance companies


  • Large aquaculture companies that are professionally managed and have a large information need from the perspective of risk management, and focus on the development of tools for better addressing critical situations in specific locations.

Insurance companies

  • interested in obtaining objective information on the occurrence of certain water related plagues, their frequency, and intensity, from a risk perspective. Fisheries
  • Local authorities
  • Recreation and tourism industry
  • divers


The current off-shore aquaculture industry is taking place in an open sea environment with which it interacts at several levels.  The cages with fish present an environmental influence on the surrounding ecosystem (feed, medicine, fish excrements) as well is being influenced by this natural environment.

The user needs are improved monitoring capabilities in terms of resolution, time of delivery (NRT), synoptical but also detailed spot measurements, recognition of threatening amounts of biomass, its decay and its species composition. Delivery of the information to operations at sea using satcom connections. The users are involved in all levels of the project; defining user needs and requirements, , specification of the integral solution and pre-prototype, testing of the prototype services and providing feedback and recommendations (with a trace-back of the original user requirements). The users test the in-situ observation instrument to assess the usability in the Demonstration phase. 

  • Monitoring and forecasting of harmful algae presence, based on an in-depth understanding of the factors contributing to HABs
  • Monitoring of the individual parameters that promote occurrence of HABs
  • Monitoring and forecasting of the presence of harmful algae presence
  • Monitoring and forecasting of the presence of harmful algae presence under cloud cover
  • Monitoring and forecasting of harmful algae presence
  • Timely identification of presence of harmful algae species
  • Simultaneous spatial identification of individual harmful algae species
  • Optimal and effective mitigation procedures
  • An integrated and comprehensive decision support  system (DSS)

Service/ system concept

The intended integral solution is based on Earth observation of water quality using historical (ENVISAT), current (MODIS, VIIRS)  and upcoming satellites (Sentinel 2 and 3). The Earth observation products are used to identify water quality anomalies at distances from user operations in a timely manner. The products are delivered to the user in near real-time to allow them to take measures based on perceived threats. To complement the service users have been instructed in the use of a handheld optical devices allowing them to inspect water quality locally and to determine more in detail the cause of the water quality anomaly. Earth observation satellite communication is the main space asset for this project, but also use is made of accurate GPS determinations to direct water sampling teams to places where a specific water quality anomaly has been detected. 

Space Added Value

The intended to integral solution is based on Earth observation of water quality using historical (ENVISAT) and upcoming satellites (Sentinel). The Earth observation products is used to identify water quality anomalies at distances from user operations in a timely manner. The products are delivered to the user by means of satellite communication in near real-time to allow them to take measures based on perceived threats.

To complement the service users have been instructed in the use of a handheld optical device that allows them to inspect water quality locally and to determine more in detail the cause of the water quality anomaly.

Next to earth observation and satellite communication as space assets for this project, use is also made of accurate GPS determinations to direct inspection teams to places where a specific water quality anomaly has been detected.

Product Benefits

The added value brought to the users by the integrated solution can be listed as follows:

  • Reduced risk of harmful algae damages, creating a lower perceived risk on the company value by financial markets (MH is quoted on the Oslo Stock Exchange)
  • Lower perceived risk for banks, leading to lower interest rates
  • Lower perceived risks by insurance companies, leading to lower insurance rates and lower deductible structures and increased sales of insurance policies to the sector
  • Higher insurance rates lead to lower perceived risks for the sector
  • Long term economic stability in salmon production
  • Reduced staff costs as a result of lower stress as a result of better understanding of the incidence of harmful algae
  • Better understanding of ecosystem dynamics leads to better informed decisions for future farm locations

Societal (global consumers, environmental authorities, regional inhabitants):

  • Production of a lower priced source of high quality proteins
  • Better understanding of the ecosystem (including harmful algae incidence) leads to better production licensing system for aquaculture production
  • Better understanding of feeding behaviour of salmon, leading to lower feed spillage in the environment that is surrounding fish farms

Service providers (laboratories, monitoring equipment suppliers, (satellite) data providers)

  • Prolonged and integrated use of monitoring equipment and laboratory testing leads to better understanding of the importance of the critical parameters in the particular eco-system
  • More stable production environment leads to higher employment at fish farms, processing factories, wholesale and retail operations

Product Features

The study proposes a zoom-in approach where satellite data is used to monitor large areas to timely identify water quality anomalies combined with in-situ data collection to identify the exact nature of the anomaly. For the in-situ data collecting one of the partners developed the WISP monitor, which is now used at various place around the world to monitor ecological water quality data in near real time in medium to small water bodies.

Near real time data and their interpretation will be provided to the end users, enabling the end users to act if and when required. Both economic and public drivers are at stake.

The service will use the following space assets in order of importance: earth observation, satellite communication and GPS. These assets are crucial for the intended services to the end users.

Key Issues

There is currently no methodology for reliable determination of detailed real time information on algae concentrations (especially in a spatial extent). Also, reliable real time information on the (spatial) abundance of specific algae is not available. Laboratory methodologies are time consuming, and typically take several days.

Current Status

The project has started in July 2013, and investigated the user needs, user requirements and part of the viability analysis. A number of meetings have been organized to iterate the user needs and requirements.

The production and harmful algae season of 2014 in the West Coast of Canada was used to collect data and analyse in detail available information, as a basis for the development of the integrated service.

The consortium was invited to present its technology at the Aquaculture Insurance Conferences in Istanbul (2013) and Hong Kong (2014), and in 2014 published a paper on Aquaculture Risk Management in a World Bank publication (FARMD) together with representatives of the aquaculture insurance industry.

The Feasibility Study concluded with a Final Presentation on the 23rd of April 2015 where the presence of a representative of Marine Harvest Canada. A Demonstration Project is currently in preparation together with Marine Harvest to develop further the potential of the services analysed through the Feasibility Study

Project Managers

Contractor Project Manager

Marco Pieterse
BlueLeg Monitor BV
Pieter Zeemanstraat 9
8606JG Sneek

ESA Project Manager

César Bastón Canosa
Keplerlaan 1, P.O. Box 299
2200 AG Noordwijk
+31 (0) 71 56 56479

Status Date

Updated: 16 July 2015 - Created: 01 July 2014