M A I N   N E W S

WHY SUKHNA IS DYING-III
A TRIBUNE INVESTIGATION
Sukhna: Death by choking
Smriti Sharma Vasudeva
Tribune News Service

Chandigarh, June 4
Sukhna Lake owes its origin to a Swiss-French architect and his Indian associates. Now another ‘foreign hand’ is choking it — a weed that has its origins in Canada.

While lakhs of tonnes of silt flowing down into the Sukhna Lake has often been recognised as the cause of its slow but sure death, little was it realised that the floating greens at the bottom of the lake were as beautiful as they were deadly.

The Sukhna is decaying due to three weeds that are eating into the water body. Two have been identified as Hydrilla and Valus, commonly found in water bodies. However, the third remained a mystery and perplexed officials of the engineering, horticulture and forest departments. After its sample was sent to Canada, the weed was identified by the country’s State Noxious Weed Control Board as the Curly Leaf Pondweed (Potamogeton Cripus). How it got to the Sukhna Lake remains a mystery.

The Canadian agency has stated that the weed grows entirely underwater and usually grows early in spring. It is an invasive plant and forms surface mats that interfere with aquatic re-creation. In fact, this weed has been noted as a severe nuisance. The cost for controlling this weed can run into millions of dollars, depending on the size of the lake, states the reply.

Earlier, samples of this mystery weed were sent to Panjab University’s Botany Department and also to the Punjab Agriculture University (PAU) in Ludhiana by the UT’s Forest Department for identification, but to no avail.

As a temporary measure and for biological control, the UT Administration has put 5,000 Grass Carp fish, which is known to eat this weed, near the measuring gauge. The fish was bought from local fish farms. “We first experimented with smaller number of fish so as to see if this specie gels well with the existing aquatic life in the lake” said UT Finance Secretary-cum-Head of Engineering Department, Sanjay Kumar.

However, the Grass Carp will hardly be able to control aquatic vegetation in the first year they are stocked. “The stocking rates of Grass Carp to control the Curly Leaf Pondweed are usually in the range of a mere 7 to 15 per cent per surface acre,” states the Canadian agency.