One of the challenges that arise by using surface water as a source for drinking water production, is the development of phytoplankton in rivers and reservoirs. It can disturb the water treatment in many ways.
The most rapid method to quantify phytoplankton biomass is the measurement of chlorophyll in the water. The test is performed in a few hours and results are presented in µg/l chlorophyll a.
As an indication of the state of deterioration of the phytoplankton, the concentration of phaeophytin a is also reported. The method is BELAC -accredited.
The ways that water blooms of phytoplankton disturb water treatment are: filter clogging by larger filamentous algae, mostly diatoms ; filter penetration by small motile algae, and the production of bad taste and odour, mostly by blue-green algae.
Our chlorophyll determination consists of filtration of a water volume, followed by extraction in warm ethanol, and spectrophotometric detection.
An acidification step allows correction for phaeopigments.