Cut in Indus River flow contaminates water
As the Indus River System Authority (IRSA) has drastically cut flows in the Indus River, the effects on agriculture as well as on human health have begun to surface in Sindh.
Awakening to the aggravating situation of the sudden rise of total dissolved solids (TDS) in the river water, the authorities in Hyderabad have requested the Sindh Irrigation Department to increase water discharge in the river.
On Thursday the water testing lab of the Water and Sanitation Agency (WASA) found as high as 790 milligram per litre TDS in a sample taken from the river with 8.4 pH and 120 turbidity. After filtration at WASA's New Treatment Plant on Jamshoro Road the TDS reduced just by around 10% to 702 mg/litre.
According to the WASA Acting Managing Director Zeeshan Malik, the agency tries to maintain TDS at 500 mg/litre or less in the filtered water which is supplied to the city. The World Health Organization (WHO) has rated below 300 TDS as perfect for humans even though the readings between 300 to 600 are not considered bad enough.
TDS represents the concentration of dissolved substances, both inorganic and organic, in water. The common inorganic salts include the cations like calcium, magnesium, potassium and sodium; and the anions like carbonates, nitrates, bicarbonates, chlorides and sulfates.
The high levels of TDS can cause gastrointestinal problems such as stomach pain and diarrhea, and in extreme cases, cause acute or chronic kidney and liver diseases.
The situation in Hyderabad, however, is expected to become worse in the days to come because of the shrunken flows in the Indus River.
On Thursday the Sindh Irrigation Department recorded 3,700 cusecs water upstream of the Kotri Barrage. Canals from Kotri Barrage bring water to WASA's filtration plants in Hyderabad.
Malik told The Express Tribune that the agency has started to advise the people to boil water at home before drinking. He said home based filtration techniques are also being shared with the consumers. According to him, the WASA started to receive complaints about high TDS levels over a week ago. The agency uses alum and chlorine for the filtration. Due to the huge disparity between the city's demand and WASA's filtration capacity, the due time required for settlement of solid substances in water is often not given.
WASA supplies filtered water, although of questionable quality, to most parts of the city. Yet many parts of Latifabad taluka are supplied water directly from the downstream river without fulfilling the required processes of the filtration.
Deputy Commissioner of Hyderabad, Tarique Qureshi, has written a letter to Irrigation Secretary to raise the TDS problem caused by the reduced river flows. Referring to the WASA's water lab reports, he described the situation as 'alarming'.
"The engineer concerned of the Irrigation Department may be informed to release more fresh water so that TDS scale may decrease to acceptable limits." According to him, owing to the low river discharge WASA's reservoirs are also being filled with toxicity. The DC called for immediate increase in the river water discharge to address the problem.
Published in The Express Tribune, March 29th, 2024.