title: Estimating the risk of cyanobacterial occurrence using an index integrating meteorological factors: application to drinking water production.
abstract: The sudden appearance of toxic cyanobacteria (CB) blooms is still largely unpredictable in waters worldwide. Many post-hoc explanations for CB bloom occurrence relating to physical and biochemical conditions in lakes have been developed. As potentially toxic CB can accumulate in drinking water treatment plants and disrupt water treatment, there is a need for water treatment operators to determine whether conditions are favourable for the proliferation and accumulation of CB in source waters in order to adjust drinking water treatment accordingly. Thus, a new methodology with locally adaptable variables is proposed in order to have a single index, f(p), related to various environmental factors such as temperature, wind speed and direction. The index is used in conjunction with real time monitoring data to determine the probability of CB occurrence in relation to meteorological factors, and was tested at a drinking water intake in Missisquoi Bay, a shallow transboundary bay in Lake Champlain, Québec, Canada. These environmental factors alone were able to explain a maximum probability of 68% that a CB bloom would occur at the drinking water treatment plant. Nutrient limitation also influences CB blooms and intense blooms only occurred when the dissolved inorganic nitrogen (DIN) to total phosphorus (TP) mass ratio was below 3. Additional monitoring of DIN and TP could be considered for these source waters prone to cyanobacterial blooms to determine periods of favourable growth. Real time monitoring and the use of the index could permit an adequate and timely response to CB blooms in drinking water sources.
authors.affiliation: École Polytechnique de Montreal, Civil, Mineral and Mining Engineering Department, P.O. Box 6079, Station Centre-ville, Montreal, Quebec, Canada H3C 3A7. Electronic address: mouhamed.ndong@polymtl.ca.
authors.forename: Mouhamed
authors.initials: M
authors.lastname: Ndong
authors.affiliation: Department of Biological Sciences, Université du Québec à Montréal, C.P. 8888, succ. Centre-ville, Montréal (Québec), Canada H3C 3P8.
authors.forename: David
authors.initials: D
authors.lastname: Bird
authors.affiliation: Department of Engineering, Faculty of Agriculture, Dalhousie University, PO Box 550, Truro-Bible Hill (Nova Scotia), Canada B2N 5E3.
authors.forename: Tri
authors.initials: T
authors.lastname: Nguyen-Quang
authors.affiliation: École Polytechnique de Montreal, Civil, Mineral and Mining Engineering Department, P.O. Box 6079, Station Centre-ville, Montreal, Quebec, Canada H3C 3A7.
authors.forename: Marie-Laure
authors.initials: ML
authors.lastname: de Boutray
authors.affiliation: École Polytechnique de Montreal, Civil, Mineral and Mining Engineering Department, P.O. Box 6079, Station Centre-ville, Montreal, Quebec, Canada H3C 3A7.
authors.forename: Arash
authors.initials: A
authors.lastname: Zamyadi
authors.affiliation: LEESU, Ecole des Ponts ParisTech, Université Paris-Est, 6 et 8 avenue Blaise Pascal, Cité Descartes, 77455 Marne la Vallée Cedex 2, France.
authors.forename: Brigitte
authors.initials: B
authors.lastname: Vinçon-Leite
authors.affiliation: LEESU, Ecole des Ponts ParisTech, Université Paris-Est, 6 et 8 avenue Blaise Pascal, Cité Descartes, 77455 Marne la Vallée Cedex 2, France; AgroParisTech, 16 rue Claude Bernard, 75005 Paris, France.
authors.forename: Bruno J
authors.initials: BJ
authors.lastname: Lemaire
authors.affiliation: École Polytechnique de Montreal, Civil, Mineral and Mining Engineering Department, P.O. Box 6079, Station Centre-ville, Montreal, Quebec, Canada H3C 3A7.
authors.forename: Michèle
authors.initials: M
authors.lastname: Prévost
authors.affiliation: École Polytechnique de Montreal, Civil, Mineral and Mining Engineering Department, P.O. Box 6079, Station Centre-ville, Montreal, Quebec, Canada H3C 3A7.
authors.forename: Sarah
authors.initials: S
authors.lastname: Dorner
mesh_terms: D000458:Cyanobacteria; D060766:Drinking Water / Q000382:microbiology*; D060106:Lakes / Q000382:microbiology; D016015:Logistic Models; D014871:Water Microbiology; D014887:Weather
chemical_list: D060766:Drinking Water
keywords: Cyanobacteria; Drinking water intake; Early warning systems; Meteorological index; Nutrient mass ratios; Wind