RAWALPINDI, Feb 17: The Biological Oxygen Demand (BOD) of Rawal Lake water has jumped up to the alarming level of 680 milligram per litre (mg/l) as compared to the 80 mg/l approved by the National Environmental Quality Standard (NEQS) for ordinary waste and surface water.

The fact surfaced during a meeting of the Rawal Lake Catchment Management Committee (RLCMC) held here on Tuesday in the backdrop of the government's rising concern over the high level of pollution in Rawal Lake and its sources. The lake is a source of water supply to 1.3 million people.

During the meeting, the Water and Sanitation Agency (Wasa) managing-director, Brig Pervez Mehmood Khan (retired), also got infuriated over the increasing contamination in the lake and said he had been supplying contaminated water to his consumers, as the other departments concerned were not playing their due role in controlling pollution in the lake. Journalists also attended the meeting.

BOD, the most widely used parameter of organic pollution, is applied to both waste and surface water. The method involves measurement of the dissolved oxygen used by the microorganisms in biochemical oxidation of the organic matter.

The NEQS has approved 80 mg/l BOD for normal waste and surface water. However, the BOD requirement of Rawal lake and its sources, which include four major and 43 small streams, has increased to an alarming level.

Similarly, the Chemical Oxygen Demand (COD) of the Rawal Lake has also skyrocketed from 17 mg/l in 1995 to 1020 mg/l in 2003, the meeting was told. The meeting also discussed the reasons behind contamination.

It noted that there were 170 poultry farms and 360 sheds in the catchment area of the Rawal Lake and all their waste was disposed of in the lake. Similarly, the unplanned human settlements in the catchment areas of the lake including, Bhara Kahu, Malpur, Banni Gala and Noorpur Shahan and as many as ten other villages, is the main reason for pollution of the lake.

The population of these areas, which fall in the jurisdiction of the Murree-Kahuta Development Authority (MCDA), is likely to cross the 10,000 figure. There is no planned sewerage and drainage system in the area and waste water joins the lake's sources.

Around 2,000 visitors throng Chatter Park during weekdays and dispose of their waste in the stream joining the lake. Many people also wash their cars in the stream.