Base-Line Study for Determination of Colour in Siahrud River of Ghaemshahr

The objective of this study was to establish the source, level and impact of colour in Siyahrud river in the vicinity of Ghaemshahr in order to set a colour consent that would safeguard against objectionable discolouration of the river water. This was carried by adopting a simultaneous programm of perception studies and spectroscopic analysis of the respective water samples from seven sample sites that were selected on the basis of sewage discharging location during eight weeks of sampling. Samples were filtered through a 0.45μm filter and absorbance in a 1cm cell measured at a range of wavelengths between 400 and 700 nanometer. This investigation has shown that the source of this contamination was mainly from Ghaemshahr textile industry branch 1 and to some extent from Ghaeamshahr canning factory. Perception studies and spectroscopic colour data enable a proposal to be put forward as the water quality objectives for colour consent system based on spectroscopic absorbance data. The proposal was assumed to ensure the visual acceptability of the siahrud river by preventing the levels of coloured effluents becoming detectable in the water.