ACADEMIA ROMÂNĂ Revue Roumaine de Chimie http://web.icf.ro/rrch/ Rev. Roum. Chim., 2010, 55(4), 285-291 ASSESSMENT OF POLLUTANT TRANSPORT AND RIVER WATER QUALITY USING MATHEMATICAL MODELS Elisabeta-Cristina ANI a,b,* , Michael George HUTCHINS c , Andrzej KRASLAWSKI a and Paul Serban AGACHI b a Department of Chemical Technology, Lappeenranta University of Technology, Skinnarilankatu, 34, FIN-53851, Lappeenranta, Finland b Faculty of Chemistry and Chemical Engineering, “Babes-Bolyai” University Cluj-Napoca, No. 11, Arany Janos Street, 400028, Cluj-Napoca, Roumania c Centre for Ecology and Hydrology Wallingford, Maclean Building, Crowmarsh Gifford, Wallingford, Oxfordshire, OX10 8BB, UK Received September 22, 2009 This paper presents (1) general considerations related to the development of two mathematical models for non-conservative transport of nitrate and ammonium under unsteady water flow conditions; (2) their application to predict the transport of pollutant in both customary and accidental pollutant release circumstances; and (2) a discussion related to models use in water quality management. The studied river stretch is part of the River Swale in England, where pollutants are discharged by multiple point sources and also by tributaries. Experimental data was used for model development and verification. The models are useful to (i) assess the downstream river distance affected by pollutant release; (ii) estimate environmental damage; (iii) support decisions on where and how to counteract pollutant discharge; and (iv) also to support the further development of more refined water quality simulation tools. INTRODUCTION ∗ During the past years there was major public interest concerning the management of water resources. A hot spot of this field is the availability of water of acceptable quality under circumstances of pollutant discharge in rivers. The water quality management in such situations requires fast decisions based on knowledge related to the distribution of pollutant concentration along the river downstream of the releasing source. This information can be facilitated by computer tools such as mathematical models for pollutant transport in rivers. The pollutant transport modelling literature is rich in information regarding the transport and transformations of nitrate (NO 3 ) and ammonium (NH 4 ), often published along with other nutrients (e.g. phosphorus compounds). This information regards: (1) in-stream models for the prediction of pollutant concentration; 11,6 (2) software for water ∗ Corresponding author: eani@chem.ubbcluj.ro quality modelling in large river networks; 4,7 (3) water quality assessment studies; 12 or (4) the transport of nutrient fluxes in catchments. 9,10 Some of these studies consider River Swale, 4,7,9,10 but none of them is focused on the prediction of pollutant transport at small time steps (less than one hour) in short river stretches (few kilometres) or after accidental release. This is the added value of the present paper compared to previous work. This paper presents the application of two mathematical models for the transport of nitrate and ammonium along a river stretch. The models are capable to predict pollutant concentration along the river at small time steps (minutes) under customary pollutant discharge (model I) and also in the case of accidental release (model II). Experimental data regarding river channel characteristics and concentration measurements in normal pollution conditions was used for model development and verification. CORE Metadata, citation and similar papers at core.ac.uk Provided by NERC Open Research Archive