Four samples of water were taken for analysis from Kala Shah Kaku Industrial Estate, near Lahore, Pakistan. These were:
I) ‘Pure’ water of the channel Dek Nullah,
II) Wastewater of Ravi Rayon Limited,
III) Wastewater of Ittehad Chemicals, and
IV) Dek Nullah ‘polluted’ water after the discharge into it of wastewater from two industries, namely Ravi Rayon Limited and Ittehad Chemicals.
The analysis of these waters showed that sample I was the best in quality (medium-salinity and low-sodium water: C2-S1), sample II was of the quality class C3-S1 (high-salinity and low-sodium water), sample III was found to be of the poorest quality (very-high-salinity and very-high-sodium water: C4-S4), while sample IV was of relatively bad quality (high-salinity and mediumsodium water: C3-S2). Only the wastewater of Ittehad Chemicals had some sediment in it, the qualitative analysis of which showed the presence of oxalates, sodium, iron, and magnesium.
The study of planktonic biota in Dek Nullah ‘pure’ and ‘polluted’ waters showed that they were more diverse in the former than in the latter; indeed, unless Bacteria are classed as fauna, there was no representative of these last in the ‘polluted’ water.
The industrial wastewater effluents are being discharged into Dek Nullah, and this ‘polluted’ water is being used for irrigation by the farmers operating along its downstream course. The effects of this water on Rice germination were studied, and it was found that such germination was significantly greater in Dek Nullah ‘pure’ water than in its ‘polluted’ water.
Dek Nullah ‘polluted’ water may deteriorate further with time, as more and more wastes are added to it, and it may have deleterious effects on soils when used for irrigation purposes—causing salinity and sodicity problems unless proper management techniques are adopted.