urban lake water quality cross research perspectives ... - LEESU

9th WWW YES, Belo Horizonte MG, Brazil 26-30 October 2009 – keynote presentation
URBAN LAKE WATER QUALITY
CROSS RESEARCH PERSPECTIVES BETWEEN
BRAZIL AND FRANCE
Brigitte VINÇON-LEITE, Briac LE VU, Bruno LEMAIRE, Sarah JUNG and
Bruno TASSIN
Laboratoire Eau, Environnement et Systèmes Urbains LEESU (Université Paris-Est,
AgroParisTech), UMR-MA 102, Ecole des Ponts ParisTech, 6-8 avenue Blaise Pascal,
Cité Descartes, 77455 Marne-La-Vallée Cedex 2, France.
(E-mail: bvl@cereve.enpc.fr)
Keywords
Lake, Phytoplankton; sediment core; PCB; urban runoff; real time; monitoring system
ABSTRACT
This paper will present the issue of water quality monitoring in urban lakes, at two different time and
space scales. It aims at initiating a reflection about how it could be investigated in a joint French-
Brazilian research project. Two topics which will addressed: (1) high-frequency, autonomous monitoring
system of phytoplankton dynamics and (2) urban storm water monitoring with sediment core analysis.
Lakes located in densely urbanized watersheds have essential functions for the city dwellers. In the
European Union, aquatic systems are monitored and restored according to the Water Framework
Directive (WFD). In this context, the monitoring programmes have two main objectives: to assess the
ecological status of natural and artificial lakes inside homogeneous hydroecoregions and to survey the
effect of restoration measures.
Phytoplankton is a key element for the establishment of the ecological status in urban lakes: the
composition and biomass of phytoplankton as well as the frequency and intensity of phytoplankton
blooms are to be monitored. Among the phytoplankton groups, the cyanobacteria are specifically targeted
because many species, potentially toxic, can threaten public health and impair the water uses.
The commitment of monitoring phytoplankton blooms in the numerous lakes requires reliable, costeffective,
easy-to-handle, monitoring systems (Allan et al., 2006; Dworak et al., 2005). High-frequency
monitoring systems are useful, since episodic measurements may not enable the understanding of the
local determinants of ecosystem dynamics (Carstensen, 2007). Autonomous monitoring stations offer
further advantages: (1) for surveying remote sites; (2) for dealing with the scarcity of qualified personnel
to perform sampling, chemical analysis and phytoplankton counting, (3) for reducing the cost due to
repeated analyses.
The monitoring system presented in this paper has been developed within the PROLIPHYC project.
Primarily aimed at assessing phytoplankton growth, it consists in the following items: design of a
freshwater-adapted measurement buoy, remote transmission of the data (water temperature, Chlorophyll,
Oxygen and meteorological data), automated integration of data into predictive modelling, warning
procedure development. In this paper, the methodology of the project is outlined; the overview and the
implementation of a buoy in the urban Enghien Lake (Ile-de-France) are described. An overview of the
collected data during 2009 spring and summer is presented.

9th WWW - YES, Belo Horizonte MG, Brazil 26-30 October 2009 - keynote presentation
On the other hand, urban stormwater runoff is of major concern considering anthropogenic pollution in
receiving water bodies. When other sources of pollution, especially waste water, are under control, they
turn out to be the main source of pollution in urban areas. Urban runoff can be significantly contaminated
by mineral and organic micropollutants originating chiefly from roof and road runoff (Brown and Peake
2006, Davis et al. 2001, Gromaire-Mertz et al. 1999). Yet, the part of urban runoff on the contamination
of receiving water bodies is still difficult to assess.
Sediment core analysis is an excellent tool to monitor the historical trends of various persistent organic
contaminants. Reconstruction of historical inputs of anthropogenic chemicals is important for improving
management strategies and evaluating the success of recent pollution control measures. In this paper, we
will present the main results obtained on Lake Pampulha’s sediment cores (Jung 2009) with a
methodology firstly developed to evaluate the impact of urban runoff on a large French lake (Lake
Bourget). Four sediment cores, collected in May 2007 in Lake Pampulha, were analysed for
polychlorobyphenyls (PCB) in order to determine the evolution of the inputs linked to the development of
the urbanisation on the catchment during the last decades.
REFERENCES
• Allan I, Vrana B, Greenwood R, Mills G, Roig B, Gonzalez C. 2006. A "toolbox" for biological
and chemical monitoring requirements for the European Union's Water Framework Directive.
Talanta 1st Swift-WFD workshop on validation of Robustness of sensors and bioassays for
Screening Pollutants - 1st SWIFT-WFD 2004 69:302-322.
• Brown, J. N. and Peake, B. M. (2006). Sources of heavy metals and polycyclic aromatic
hydrocarbons in urban stormwater runoff. Science of The Total Environment, 359(1-3): 145-155.
• Carstensen J. 2007. Statistical principles for ecological status classification of Water Framework
Directive monitoring data. Marine Pollution Bulletin Implementation of the Water Framework
Directive in European marine waters 55:3-15.
• Davis, A. P., Shokouhian, M. and Ni, S. (2001). Loading estimates of lead, copper, cadmium, and
zinc in urban runoff from specific sources. Chemosphere, 44(5): 997-1009.
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implement the WFD. Environmental Science & Policy Research & Technology Integration in
Support of the European Union Water Framework Directive 8:301-306.
• Gromaire-Mertz, M. C., Garnaud, S., Gonzalez, A. and Chebbo, G. (1999). Characterisation of
urban runoff pollution in Paris. Water Science and Technology, 39(2): 1-8.
• Jung, S. (2009), Impacts des rejets urbains sur les milieux aquatiques Analyse historique de la
contamination urbaine dans les sédiments du lac du Bourget (Savoie, France) et du lac de
Pampulha (Belo Horizonte, Brésil) Thèse de doctorat de l'Ecole Nationale des Ponts et
Chaussées
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