NEW DELHI: Industrial houses will soon be wary of putting up projects in places which require clearing of trees with the Supreme Court remaining firm on Tuesday on calculating the ‘real value’ of a tree that would include cost estimation of volume of oxygen it would have emitted into the atmosphere in its lifetime.

“We need economists to work with environmentalists to calculate the real value of trees,” a bench of Chief Justice S A Bobde and Justices B R Gavai and Surya Kant said while suggesting to the West Bengal government that it may have to realign flyover projects to avoid cutting of trees. The Bengal government, through senior advocate A M Singhvi, had said the authorities had decided to plant five times the number of trees felled for the flyovers which had become essential to avoid accidents.

The CJI said, “You may plant a tree but it is difficult to compensate the death of an existing tree. It may be a little more expensive to realign flyovers and any other project, for that matter, than cutting trees. If one takes a holistic view, it will actually be not expensive if the true value of trees, taking into account the price of oxygen they will emit in their lifetime, is calculated.

“This is the third case I am hearing involving cutting down of trees. Others were the Mumbai Metro and the Mumbai coastal road cases. Address us on the issue of calculating the true value of a tree. We will see how we can lay down some principle on valuation of trees.”

Appearing for the Association for Protection of Democratic Rights, which has challenged felling of trees in West Bengal’s flyover project, advocate Prashant Bhushan said he had faced a similar question while arguing a PIL against limestone mining in the Doon valley. “There were several limestone aquifers. Limestones absorb rain water and gradually release them, helping preservation of water. How does one calculate the value of an aquifer? Apart from emitting priceless oxygen for years, trees are also important aquifers,” he said.

Inclusion of price of oxygen emitted over their lifetime in the valuation of trees was first mooted by the CJI in the case relating to the Bengal flyover project.

The NGO has challenged a Calcutta HC decision permitting the Bengal government to cut down 356 trees for construction of five railway overbridges (ROBs) at Kazipara , Ashok Nagar , Habra-I, Habra-II and Bongaon and expansion of NH-112, or Jessore Road .

The CJI had asked, “Why do authorities, while computing environmental compensation, not take into account price of volume of oxygen it will release into the atmosphere in its lifetime? Look at the amount of oxygen generated by a single tree in its lifetime. Value of oxygen generated by a tree in its lifetime should be taken into account in determining damage to environment caused by its felling.”

