The army has allowed Ganga Sagar pilgrims to camp on the Maidan, but with a rider — this is the last time the city’s lungs can be used for the purpose.

The decision follows a nod to the Book Fair to get back to the greens by the army, the custodians of the Maidan.

The army had earlier turned down the state government’s plea to allow pilgrims to camp on the Maidan on their way to Ganga Sagar, which is about 130 km from the city.

The Ganga Sagar mela starts on January 12 and will continue for three days. Lakhs of pilgrims, most of them from outside the state, attend the annual event on Sagar Island, in South 24-Parganas.

While permitting the pilgrims to camp on the Maidan, the army directed the state government to ensure that there is no environmental damage to the greens.

The government assured the army that it would clean the Maidan after the structures built for the pilgrims are demolished.

“The pilgrims cause the highest degree of environmental damage by converting a part of the Maidan into an open-air lavatory. Even the high court judges had taken note of the damage to the Maidan,” said environment activist Subhas Dutta.

Wing Commander R.K. Das said: “We do not want any damage to the Maidan. We have, therefore, imposed restrictions on voluntary organisations setting up camps on the Maidan.”