Sources told Business Recorder here on Monday that Hudiara drain, which originates from Batala (District Gurdaspur East Punjab, India) and after covering 40 kilometres enters Pakistan near Laloo village, carries untreated sewage. "Between Laloo village and Mohlanwal village, a stretch of 55 kilometres, the drain receives untreated effluents from hundreds of industrial units and domestic sewage from some parts of Lahore city and cantonment areas and of other small villages also enters the drain," they added.
According to him, this drain was originally a storm water drain. Nevertheless, dumping of industrial and domestic wastewaters has turned it into a perennial drain. Its annual average discharge at its confluence with the River Ravi is about 500 cusecs. There are hundreds of industrial units of different natures situated along the Hudiara Drain on both sides of the border, which discharge a huge amount of effluent into it. Hence, the drain water, polluted with high content of heavy metal and biological contaminants, is not fit for agricultural irrigation and also it cannot support any aquatic life. Moreover, it is also likely to cause contamination of subsoil water.
Justifying the reason to carry out a new study, the sources said though a number of separate studies on Hudiara Drain had been conducted by different organization and researchers, but no study served the purpose of designing wastewater treatment facility.
"Some data is available with the Environmental Protection Agency on number and types of industries discharging their effluents into this the drain. The EPA Punjab also surveyed the drain under the project titled 'Monitoring of Surface Water Bodies in Punjab'. According to the report, the drain has an average discharge of 430.56 cusecs. The values of Biochemical Oxygen Demand (BOD) and Chemical Oxygen Demand (COD), a measurement for water quality, were measured in low flow seasons in 2008 and 2009. The average value of BOD and COD of these two seasons were found to be 134 and 408 mg/L, respectively," they added.
Interestingly, most pristine rivers will have a 5-day BOD below 1 mg/L and moderately polluted rivers may have a BOD value in the range of 2 to 8 mg/L. This drain is also responsible for adding 141.15 tons of organic loads to the River Ravi. According to EPA lab analysis report conducted in September 2013, the values of BOD, COD, TDS, TSS, Chloride, Sulphate, and Sulfide at entry point of drain in Pakistan near village Lallo, Lahore, are 208 mg/L, 458 mg/L, 780 mg/L, 240 mg/L, 75 mg/L, 198 mg/L, and 20 mg/L, respectively. Similarly, the values of these parameters before mixing of Hudiara Drain into River Ravi (covering a distance of about 55 km) near Mohlanwal Lahore, are 134 mg/L, 305 mg/L, 580 mg/L, 90 mg/L, 65 mg/L, 168 mg/L, and 40 mg/L, respectively. The results show that the values of BOD, COD, TSS (at entry point) and Sulphide exceed the NEQS limits. Similarly, historic data on discharges in the drain is available with the Irrigation Department. The consultant firm will also be required to review all available relevant studies on Hudiara Drain. The proposed treatment of Hudiara Drain's wastewater will improve the aquatic system of River Ravi and will also improve the water quality for downstream water use, sources said.
Copyright Business Recorder, 2017