Fresh algae blooms threaten the Dal lake

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Faisal Khan (2)
Algae returns: The algae, which first emerged in 1990 and had since been largely controlled, is resurfacing now in a more virulent form (Photo: Faisal Khan)

Towards the end of July, just two weeks into the ongoing mass unrest over the killing of militant commander Burhan Wani, a thick coat of red algae spread through a wide swathe of Dal lake, the mascot of Kashmir’s timeless beauty and a magnet for tourists visiting the state from all over the world.

The algae, environmental experts claim, first emerged during August 1990 and had since been largely controlled, thanks to a multi-crore rupee clean-up funded by the government of India. But it is resurfacing now in a more virulent form. It not only points to the deteriorating health of an already stressed lake but also raises questions over the direction of conservation efforts.

“The basic problem with the conservation plan for the lake is that it’s not based on a scientific understanding. It is ad hoc,” says Dr Shakeel Romshoo, head of Department of Earth Sciences, University of Kashmir. “We have only been treating the symptoms, not addressing the root cause.”

Dal has been the focus of an intense recovery effort over the past three decades. The state and the central governments have followed twin strategies of conservation and rehabilitation to rejuvenate the lake’s ecosystem and to rid it of encroachment. The plan called the Dal-Nigeen Lake Conservation Project was drawn up in 2005.

Though conservation effort funded by the Union Ministry of Environment and Forests has somehow pulled along, it has largely made a symptomatic difference to the condition of the lake. And the state government financed rehabilitation plan which includes removing encroachment and resettling the people living inside the Dal hasn’t made much of a headway, even though the plan dates back to 1987. Around 50,000 people live in 58 hamlets within the lake and around 750 houseboats are moored in its waters.

As return of the red algae makes it clear, the factors that menace the ecosystem of the lake haven’t gone away and in the absence of daily cleaning by the concerned Lakes and Waterways Development Authority (LAWDA) during the ongoing strife, have returned with a vengeance and threaten to overwhelm the water body.

“If not controlled, it could degenerate into green algae which is toxic and more dangerous, mortally injurious both to lake and the human beings,” says environmentalist MRD Kundangar. “The current bloom is an indication that the lake’s ecological fundamentals aren’t okay And our response shouldn’t be ad hoc.”

The basic threat to Dal’s survival, according to Kundangar, springs from its altered watershed over the past several decades. The lake’s once large green belt has suffered an inexorable encroachment in parts. New residential colonies have sprung up on the lake’s west and the existing colonies have become more congested including the hamlets inside Dal, together with the massive tourism-related infrastructure along its 15.5-km-long Boulevard. All the sewage and the agricultural effluents from a predominant part of these settlements empty into the lake including human excreta, from the houseboats.

Before the government installed Sewage Treatment Plants (STPs), the LAWDA figures estimated that 5.5 tonnes of phosphorous and 88.9 tonnes of nitrogen drained into the Dal each year from human settlements and farms inside and on the banks of the lake. The consequent influx of the nutrients, mostly nitrogen and phosphorus and their settling down at the lake bottom, acts as a super-fertilizer which encourages an indiscriminate growth of weeds. According to a study by Kundangar and Adnan Abubakr, this has caused drastic changes in the water quality over the years reducing its transparency by a dramatic 70 per cent.

One big fallout has been on fish diversity. The population of Schizothoracine, a local breed of fish, has declined sharply over the past three decades while the carp which was introduced in 1956 and feeds on nutrients and organic matter has thrived. According to the J&K Fisheries Department, carp makes about 80 per cent of the fish catch in Dal.

In August 2012, thousands of small fish could be seen floating on the surface of the lake dead. This was the largest fish kill in recent memory and took place in Nigeen, a smaller lake considered an extension of Dal. Experts then put down the mortality to the depleting oxygen levels due to rampant growth of nutrient-induced weeds.

Red algae, on the other hand, is a more alarming symptom of the deteriorating Dal health and also detracts from the lake’s aesthetic appeal. Though it is similarly caused by the ever-growing load of the effluents into the lake, Kundangar traces the present bloom to the “ill-advised,” de-weeding in parts of the lake.

“The weeds hold the nutrients in their roots but once you cut them, the nutrients in the sediment release directly into water, leading to growth of algae,” says Kundangar. “As long as we don’t substantially limit the nutrient load in the lake, we have to be circumspect about our routine conservation effort in the lake and pursue it on scientific lines.”

However, Romshoo sees measures like de-weeding and aeration of the lake as ad-hoc in nature which in no way would make a redeeming difference. “The untreated sewage from nearly half the Srinagar population flows into Dal. All the lake’s problems arise from this,” says Romshoo. “Weed growth, fish loss, declining water quality, can only be addressed if we arrest or treat the inflows into the lake.”

But to its credit, the government has been working on an elaborate conservation plan to rescue Dal. LAWDA has already set up five of the proposed six STPs to treat the 36.7 million litres per day of run-off into the lake. The Authority has also installed mini STPs to treat the sewage from the houseboats. There is also a plan to build around 28 kilometres long sewers along the periphery of the lake to intercept the inflow. The government also proposes to re-align the houseboats “to connect their outfalls with the sewer system.” About 10,000 cubic meter of the solid waste is collected annually by the NGOs and disposed off by the Srinagar Municipality.

The watershed management has also been taken in hand to arrest the catchment degradation through pasture development and creation of water harvesting structures. The intervention has helped over the years. From around 60,877 tons per year in 1999-2000, the load of sediment in the lake is stated to have declined to 30,000 tons by 2007 and more so since, says a study by Mir Naseem Ahmad, the then vice chairman of LAWDA.

However, the single most cause of the Dal’s deterioration over the years is the blocking of its natural drainage system as a result of the filling in of the Nallah Mar in the 1970s. The stream which passed through downtown Srinagar was fed by Dal and helped in the circulation of the lake’s water. Loss of Nallah Mar choked Dal. Now, LAWDA has tried to make Brari Nambal, a marshy waterbody near the lake, an alternative outflow channel, besides enhancing the carrying capacity of another outflow stream Nallah Amir Khan from 150 cusec to 1330 cusec.

The process of relocating Dal dwellers has been exceedingly slow. Over the past decade less than 2000 of the 6,000 families have been rehabilitated in eight colonies across Srinagar. The rest are being shifted to Rakh Arath, 940 acres of government land on the outskirts of Srinagar.

But despite all these measures, Dal is showing fewer signs of being on the road to recovering its old glory. The resurfacing of red algae has come as a reminder that something somewhere is seriously amiss.

“The problem lies in the implementation,” says Romshoo. “The conservation effort has witnessed a simultaneous progress and reversal, besides inordinate delays in execution.”

As proof, he cites the attempts at encroachment of the lake in the cover of the ongoing turmoil. Romshoo is right. Over the past month, LAWDA has registered 53 FIRs against people trying to eat into the space of the lake. The agency has also demolished 46 illegal structures around the lake’s periphery.

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