LAHORE: About 271 industrial units are discharging their wastes in the canal system, which is polluting water, while majority of underground water of the city is already highly polluted, this was revealed in a report “Situation Analysis of the Water Resources of Lahore”, prepared by WWF-Pakistan and launched here in a ceremony.
The report said that the entire municipal waste, which is collected through a network of 14 main drains, is being discharged into the Ravi River without any treatment.
The report was prepared as a European Union (EU) funded project City-wide Partnership for Sustainable Water Use and Water Stewardship in SMEs in Lahore, Pakistan.
The report revealed that the second biggest source of pollution is the Hudiara Drain and around 100 industries are located along this drain, which discharge wastewater directly into the Ravi River.
Identifying the water sources of the provincial capital, the report stated that the total surface water diverted to Lahore is 6.02 million cubic metre per day (MCM/day) and is mainly used for agricultural purposes. The Bambawala-Ravi-Badian-Deplapur (BRBD) Canal mainly feeds the command area of Upper Bari Doab Canal on the Pakistan side of the Pak-India border. The Upper Bari Doab Canal irrigates command areas of Lahore Branch, Khaira distributary, Butcher Khana distributary, Main Branch Lower and other smaller channels. The remaining flow of the BRBD Canal supplements Depalpur Canal.
The report added that the groundwater for drinking purposes is extracted from a depth of 120-200 metres (m). It is pumped for Lahore’s domestic, industrial and commercial purposes. In order to deal with the vagaries of surface water supplies, more than 10,000 tube wells have been installed for agricultural purposes. The average annual rainfall of Lahore is 715 mm.
Analysis of groundwater quality and its availability showed that due to excessive pumping, the water table depth in the central part of the city has gone below 40 m, and it is projected that by 2025 the water table depth in most areas will drop below 70m. If present trends continue, the situation will become even worse by 2040, when the water table depth in a significant part of the study area will drop below 100m or more. Extraction of water from these depths will not be technically or financially feasible. In addition there will be a growing risk of deterioration of groundwater quality.
The Babu Sabu drain is the largest contributor of organic load to the River Ravi (154.7 tons/day) while Shahdara drain is the lowest contributor with only 3.27 tons/day. According to estimates, approximately 730 tons/day of Biological Oxygen Demand load is added to the Ravi.