The BiWAS technology
BiWAS (Biological Water alarm system) is a compact, early warning system for monitoring the quality of drinking water. The system is composed of a software network that lets the users observe the water quality at multiple locations in near real time (see figure 1) and a sensor component containing two detection modules.
The software can be configured to trigger an alarm when the water quality drops below a set threshold in one or multiple locations. The sensor component can be connected directly to the water pipe (see figure 2), and can either be powered by an external power supply, or by an internal battery pack.
The Chemical Detector
The chemical detection module is an early warning system for the detection of toxic substances. The module is based on the canary principle using the bioluminescent bacteria Vibrio fischeri (see figure 3).
Under regular conditions, the bacteria glows at a set intensity. If there is no change in intensity, the bacteria are healthy and there are no toxic substances in the drinking water. When there are toxic substances, e.g. heavy metals or toxic chemical compounds present in the drinking water (see figure 4), some of the bacteria will die, and the light intensity will decrease (see figure 5).
The Biological Detector
The biological detection module takes advantage of a physiochemical phenomenon called intrinsic fluorescence. Intrinsic fluorescence occurs when a chemical compound called a fluorophore is exposed to a specific wavelength of light called the excitation wavelength, that excites the compound. This wavelength often has a high frequency. Within a short time of the compound being excited it emits a new wavelength with a lower frequency, at the emission wavelength. Some fluorophores can be found naturally in bacteria and other pathogens.
The biological detection module continuously exposes the drinking water to a high frequency excitation wavelength of a known fluorophore and measures the intensity of the lower frequency emission wavelength. If there are bacteria in the drinking water (see figure 6), they will be exposed to high frequency light (see figure 7), and emit lower frequency light (see figure 8).
The intensity of the emission wavelength is directly related to the total number of cells present in the drinking water.
We have completed a Horizon 2020 phase 1 project, and our technology is being verified in 3 verification projects partly financed by Hovedstadfondet and Oslofjordfondet. We will establish production in 2019, and start deliveries in 2020.