Bacterial contamination was found to be the cause of water contamination in Rawal Lake, which is killing fish on a large scale, revealed test reports on Friday.
Six water samples, tested by the Pakistan Environment Protection Agency, disclosed bacterial contamination in water and fish.
The water contamination was found in the water from the catchment areas.
Samples taken from different levels deep into the lake water and from the water surface at various locations, however, carried no other pollutants higher than the WHO standards except the E Coli/Coliform contamination.
There had been contradictory reports about water contamination at the Rawal Lake, but test results by the EPA and the pathology labs in the Capital detected bacterial infection in the water and in the fish blood.
Six samples were collected with one each from centre of the lake (11-metre depth), near Navy Marine (nine-metre depth), near spillway (11-metre depth), near spillway (at the surface), from the Korang river at the inlet of the lake and one near Jultrang restaurant.
Dissolved oxygen deficiency and water temperature were earlier thought to be the major factor behind fish death.
However, the water and blood test reports clarified that bacterial infection was the major cause of fish death.
The water was tested in accordance with the WHO standards to detect the pollutants but none of the components, including temperature, dissolved oxygen, chloride, COD, BOD, sodium, nitrate, sulphate, copper, iron, zinc, cadmium and potassium, was found above the WHO standards to harm the fish and human health.
All these components had been more or less within the parameters of the World Health Organisation (WHO) standards and even no viral infection was found in the fish and the water.
The Pak-EPA also sent the blood samples, taken from live fish, to a pathology lab that also revealed bacterial infection in the fish.
The fish was also infected with worse Escherichia Coli (E Coli) Klebsiella Pneumonia, Porteus Mirabilis and Pseudomonas Aeruginosa.
These tests were conducted by the City Lab in the federal capital by using the brain-heart infusion broth media for samples incubation.
"All parameters are within the permissible limits, however, there is bacterial activity in fish samples and the water," revealed the final report of tests.
The water temperature in these six samples varied from 27.4 C to 30.7 C with dissolved oxygen level varying from 4.60 to 10.70. Level of other components was also not as higher as it could kill the fish.
But, the level of E Coli that must have been zero in per 100 ml water was recorded at 60 in 100 ml sample. "Only this higher level of E Coli presence in the waters resulted in fish death," commented an expert at the Pak-EPA.
City Lab blood CP tests of fish also found no clue of viral disease in the morphology.
At present, there are no ambient standards for raw or surface water in the country, water is tested as per the WHO standards.
Laboratory tests of water sample tests, arranged by the Water and Sanitation Agency, a few days back, also showed no contamination of arsenic, mercury, lead and nitrate components.
It was found in samples tests that all the parameters were well within the permissible limits of the WHO and water was fit for drinking.
CAREFUL TREATMENT: Meanwhile, the Wasa stepped up efforts to ensure more careful treatment of the drinking water to make it pollutants free.
Though the situation remained in control, but it is astonishing that fisheries department had no particular system for carrying out tests of fish when such a situation arises.
The country lacks a regular water monitoring system and has to bear extra burden worth millions of rupees in terms of health budget and allocation for treatment of water-related diseases.
TECHNICAL BOTTLENECKS: The Ministry of Environment prepared a project of Air and Water Monitoring System, but it is pending for more than a year due to certain technical bottlenecks and awaits approval.
Environmentalists have called for proper Environmental Impact Assessment (EIA) of all the development projects as they think the development and construction in the Rawal Lake catchment area was bringing silt and debris into the lake to further contaminate this water resource mainly meant for providing drinking water to residents of Rawalpindi.
Islamabad Capital Territory administration taking cognisance of the situation immediately imposed section 144 for two months prohibiting working of cattle sheds and poultry farms established along the banks of the water inlets or Nullah that were polluting the lake water
Dr Sajid Mahmood Chohan, Sub-Divisional Magistrate (Rural) Islamabad said the situation necessitated preventing pollution of the lake water and anybody violating this order will be subject to necessary action.
People feel a dire need for a comprehensive nation-wide clean drinking water system for better health and this is high time for the government to vigorously pursue its agenda for meeting global environmental challenges.