AWWA WQTC69462

This powerpoint presentation begins by providing a brief overview of the occurrence of cyanobacteria in water resources and treatment facilities in Southern Quebec, including: regulatory options; in situ multi-probe systems; specificity of absorption of pigments;specificity of emission detection; benefits and limitations of using insitu fluoroprobes; and, potential interference with turbidity. Study objectives included the following: to calibrate the fluoroprobe with cell counts andstudy the sources of interferences; the presenceof algal biomass and turbidity; and,to monitor the concentrations of cyanobacteriaand their associated toxins using a novelmonitoring strategy combining onlinefluoroprobe measurements at the water intakeand event based additional investigations at thesource in close proximity to two water intakes. Materials and methods included: 4 YSI multi-probes at Ecole Polytechnique Montreal, one equippedwith standard and new PC probe in Australian Water Quality Center;validatingprobe measurement of Microcystis aeruginosa, Anabaenacircinalis, Scenedesmus; validating probe measurement of A. circ. + Scen.; validatingprobe measurement of M. aerug. + 3 Turbidities (inorganicturbidity Bentonite);studying the usefulness of amulti-probe system (PC, Chl-a, pH,turbidity, conductivity, temperature)for periodic and detailedmonitoring of water bodies andwater intakes. Presentation conclusions indicate the following: response of PC probe is linear with respect to theconcentration of cyanobacteria in unicellularsuspensions;the fluorescence emissions of chlorophyll ofScenedesmus and the turbidity influence of the PCreadings may lead to a significant overestimationof the number of cyanobacteria; theseinterferences are more important whenconcentrations of cyanobacteria are low;the new YSI PC probe prototype tested did notreduce the interference of Scenedesmus; in the presence of algal proliferation, thenumber of cyanobacteria at the water intakewas considerably lower than found atproximity of the intake; regulatory sampling often targets worst point insource; and,raises the issue of selecting the bestsampling site to estimate the risk at the waterintake. Includes figures.

Product Details

Edition:

Vol. - No.

Published:

11/01/2008

Number of Pages:

27

File Size:

1 file , 2.5 MB