Volume No. 7 Issue No.: 3 Page No.: 1237-1245 Jan. - Mar.2013




Thinakaran E.* and Jothiprakash V.

Department of Civil Engineering, Indian Institute of Technology Bombay, Powai, Mumbai (INDIA)


Received on : August 15, 2012




The objective of the present study is to analyze the assimilative capacity of a river Estuary, using the two dimensional pollutant transport model with different discharge rate. The study area taken into consideration is Androscoggin river Estuary, Maine County, North America. The study area of 30 km × 28 km is divided into 600 × 550 grids. The average discharge rate in the river estuary was 60 m3/sec. A sensitivity analysis has been carried out by varying the discharge from 10 m3/sec to 100 m3/sec with a step of 10 m3/sec. Initially before the sensitivity analysis, the model is calibrated with the observed tides, using the two dimensional hydrodynamic model and has been found satisfactory. The results are compared and analyzed with respect to four points, two in the river reach and two in the estuary. DO simulations shows that the presences of more DO at the maximum discharge rate when compared to the minimum discharge rate. BOD simulations show that the biological oxygen demand is more for the minimum discharge rate when compared to the maximum discharge rate. From the depth averaged 2D model, MIKE21, it is found that, at the higher discharge rates, the pollutants get dispersed faster as compared to the lower discharge rates.


Keywords : Pollutant transport, Different discharge rate, Androscoggin river, Sensitivity analysis, Tide, Hydrodynamics, MIKE21