KARACHI, June 20: Pollution level in the water of the River Indus, irrigation canals and important wetlands in Sindh is exceedingly high.

According to an official survey of the surface water quality status, water at different locations along the Indus River is extremely unsafe for human consumption and irrigation purposes.

A high Biological Oxygen Demand (BOD) has been observed all along the Indus River, and according to the Global Environmental Monitoring System (GEMS) the river is “seriously polluted”, as BOD value exceeds 6.5mg/l, says the report prepared by the Sindh Environmental Protection Agency recently.

EPA sources said that a water quality monitoring study was undertaken by the provincial environmental agency last year, with the funding of the National Drainage Programme (NDP) Sindh, with the objectives to establish a water quality monitoring programme and establish an initial baseline for the assessment of the future trend.

A comprehensive report of the study of the effects of pollution on the existing water being used for drinking and irrigation purposes by the people living across the edges of different water bodies was presented at the higher forum of the NDP Sindh for review and approval.

The source said the NDS Sindh had agreed in principle to launch a long-term study, at least for one year, in order to cover for variation in water quality for all seasons, and data might be generated for low flow, normal flow and for flooded conditions.

Under the pilot project water samples were collected at about 30 locations, including barrages, NDP drains, Indus River, major wetlands and other critical places, and various parameters were analyzed at the sampling locations as well as the regional and head office laboratories of SEPA, under the supervision of scientific officer S M Yahya.

It was learnt that samples for the study in question were collected from June 24 to July 18, 2002, a period that coincided with the rainfall in the Northern region of the country.

Referring to the samples which were taken in the flooded situation, one scientists said that when the scenario became was so alarming in such a diluted water condition, then one could imagine the severity of quality in highly concentrated condition of water.

The report says that the runoff of organic matter from sewerage and industrial effluent might be the major cause behind the presence of high values of Total Suspended Solids (TSS), Chemical Oxygen Demand (COD) and BOD in the Indus water.

The study was carried out for a limited period of time in summer, but its results clearly show the pollution level at relatively high flow, while the concentration of pollutants are to further increase at low flow in winter.

The main source of surface water in the country is the Indus Basin irrigation system, which covers about 70 percent of the geographical area of Pakistan. Cities and industries draw water from surface and discharge waste into the same stream which, in turn, become the water supplies for downstream users, the report says.

It adds that in the past dilution and natural purification were usually sufficient for such a system to perform satisfactorily, but in the recent years population and industrial growth have made it evident that waste water discharged into rivers, streams, canals and drains has already started damaging the quality of water.

The report suggests devising of monitoring mechanism at the borders of the provinces to assess the quality of water entering into the province, and that the polluter province be made liable to ensure measures to control pollution.

A hydrologist said the River Indus was the eleventh largest river in the world in terms of drainage, river discharge and sediment transport, and during its traverse it was joined by eastern and western tributaries.

The EPA collected samples from locations, including the main bridge at the Guddu Barrage, the Sukkur Barrage, the Dadu Moro Bridge, the inlet to Manchar lake, the Indus Link, the Kotri Barrage, the Sujawal Bridge, the K B feeder at the inlet (Jamshoro), the K B feeder at the Kotri Industrial Estate, the Kinjhar Lake, the inlet at the Chatori reservoir, the LBOD near Shahdadpur, the LBOD near Nawabshah, the LBOD near Mirpurkhas, the Chuki-border line zero point Balochistan and the Phuleli and Pinyari canals.

The EPA reports confirm some findings of the past as well. It says the chemical parameters found at different locations of the left bank outfall drain (LBOD) are quite varied from the start to the end of the drain.

It was observed that the quality of water found near Nawabshah and Shahdadpur could be used for irrigation purpose, but water was completely saline at the end of the LBOD. The effect of salinity on the water quality of the Indus River was also observed at the Sujawal Bridge.

The maximum concentration of the TDS at Guddu was found to be 181mg/l, whereas at Sujawal TDS was 276mg/l. The increase in the TDS may be due to the intrusion of seawater and the high salinity level of the LBOD.

Referring to BOD, COD, TDS and Dissolved Oxygen values found for Manchar and Hamal lakes, the report notes that these were high and even greater than the acceptable values laid down in the NEQS devised for municipal and industrial waste water, so the quality of water was unfit for domestic and agriculture purpose.