Todat, lakes and rivers are instrumented manually: a technician takes a water sample, which is brought to the lab to be analyzed. This is costly and quite ineffective because each data point requires human interaction, and because only a few data points can be obtained in the course of a year. Typically, water samples are only taken during the spring and summer seasons where lakes and rivers are easily accessible. As a result, there is currently no accurate lake and river ecosystem models, that would allow precise risk assessment analysis.
The evolution of sensor technology makes it possible today to replace manual sampling with automatic sampling. Optical sensors can measure abiotic parameters such as dissolved oxygen, salinity or chlorophyll concentration. Both bio- and mechanical-wiping garantee that a sensor can remain accurate while immerged in water for months. Using sensors for automatic lake and river monitoring, it is possible to increase sampling resolution in time from a measurement per month, to a few measurements per day. Such sensors are however still costly (around 100 000 DKK). The advent of MEMS optical sensors1 promise to deliver an exponential decrease in the cost and form factor of optical sensors over the next few years. At that point, automatic lake and river sampling will be cheaper and more efficient than manual sampling.
The evolution of wireless communication technologies make it possible to deploy wireless networks both underwater (there has been a 10-fold decrease in the cost of underwater modems in the last two years), and in the air (with standards such as 802.15.4, 802.11, GPRS). Using several networked sensors for lake and river monitoring, it is possible to increase sampling resolution in space from one to several location at various coordinates and depths. It is also possible to improve the quality of the collected data by correlating measurements.
The advent of sensing and networking technologies create an opportunity for innovation. Indeed, sensors and modems cannot be deployed in a lake or a river without a buoy that glues those components together into a full-fledge data acquisition system.
We design buoy systems, that fit the quality and stability requirements of our customers, are easy to deploy and maintain by technicians in the field, and so cheap so that automatic instrumentation becomes an attractive alternative to manual sampling. We base our systems on off-the-shelf sensing and communication modules.
Capoh System deployed at Zackenberg
Read more about the deployment of the Capoh system at Zackenberg.
Dan-System aps 