EyeOnWater vs Mini Secchi

The EyeOnWater concept consists of an App and a website. The app allows you as user to make a contribution to science and supply information about the water colour of fresh- as well as saline waters (lakes, rivers, coastal waters, seas and oceans) near your location or elsewhere. The measurement is sent to the central server, validated and stored, after which it is visible via the EyeOnWater website: www.eyeonwater.org What is it you measure? Water colour is an indication for life (e.g. algae) in the water. Scientists have been measuring this in marine waters via the Forel-Ule scale for more than 200 years. Your measurements will contribute to this long term observation and continue the timeseries. The EyeOnWater concept has been developed by NIOZ (scientific background), Veerder (Design), and MARIS (Technical development), with assistance from other partners in the EU funded project Citclops: www.citclops.eu Join us!

The Secchi disk is a white disk that is lowered into the water and the depth at which it disappears and reappears from sight is logged. This depth is proportional to the clarity or transparency of the water. The Forel Ule colour scale is used to classify the colour of natural waters.It consists of 21 colours ranging from blue to green to yellow to brown, and is used alongside the Secchi disk with the observer typically recording the colour of a submerged Secchi disk with this app. The app will guide you through each measurement, store location data, photos and additional observations.