Dal Lake = Srinagar’s sewage dump?

The fifteen drains releasing sewage into the Dal are:

Nishat Pipe line bund (2 sites); Lower Brein village,Brein; Sheikh Mohalla,Brein; Drain at Karpora; Laam village exit; Pump station,Hotel Heemal; Dalgate Mohalla,Dalgate (2); Jogilanker,Rainawari; Hassanabad,Saidakadal (2); Khwaja Yarbal,Saidakadal; Hazratbal (2 sites); Pump station,Habak,Suderbal (2); Umer Colony,Lal Bazar; Brarinambal drain (3sites).

Water Inlets – Telbal Nallah,BotKol and others – MeerakShah and Pishpav streamlets.

Water Outlets – Dalgate,Nalla Amir Khan and drinking water supply pipe,Nishat.

According to the Detailed Project Report prepared by the University of Roorkee’s Alternate Hydro Energy Centre,the sewage brings with it nitrogen and phosphorus which has changed physical and chemical properties of Dal waters. “There are various point – tributaries and sewage drains – and non-point sources – seepage and diffuse runoff from catchment area – that bring these nutrients to the lake,’’ the report says.

The report explains that:

• The total phosphorus inflow into the lake is about 156.62 tons,of which 4.50 tons are from nonpoint sources within the lake and the rest comes from peripheral areas,mainly through well recognized entry points.

• A total of 80.62 tons of total phosphorus leave the lake,mainly through two outlets.

• About 76.0 tons of total phosphorus is entrapped in the lake on an annual basis.

• Total inorganic nitrogen inflow to the lake amounts to 241.18 tons.

• Inorganic nitrogen outflow from the lake is about 109.22 tons.

• About 131.96 tons of inorganic nitrogen get trapped within the lake system.

• Sewage from the catchment area is a significant contributor to the nutrient load of the lake.

The report gives reasons for the changing quality of the once magnificent Dal Lake,“Water quality of the Dal Lake has been seriously altered over a period of time because of human interventions which include agricultural development in the catchment,urbanisation and waste discharge.”

Among the point sources,fifteen drains release “significant” quantities of sewage. The total Phosphorus inflow to the Dal Lake is 156.62 tons from all sources. According to the report the quantity contributed by the drains works out to be 56.36 tons. In the case of inorganic Nitrogen (NO3-N and NH3-N) these figures are 241.18 tons and 77.609 tons with a flow of 11.701 million m3/year.

Similarly from the non-point sources 4.5 tons of total phosphates and 18.14 tons of nitrogen (NO3-N and NH4-N) are added to the lake.