Several days of extreme heat and lack of rain last month have prompted the Kolkata Municipal Corporation to revise its tree watering schedule.
The civic body has asked its personnel to water trees — on median dividers and in green verges along footpaths — on all days till the end of May. Earlier, the trees were not watered on holidays.
A KMC official said they have observed that trees look withered whenever there are three or four consecutive holidays.
The move should have come earlier when Kolkata was experiencing a severe heat spell in April. The past few days have witnessed rain. The city went without showers for over three weeks till April 24.
There were also several heat wave days during the period, which was preceded by a four-month rain-less spell.
A heat wave is declared when the maximum temperature touches 40 degrees Celsius and is at least five degrees more than normal, said an official of the India Meteorological Department (IMD).
The civic body should have a mechanism in place so that it can take such decisions quickly based on the weather, said an environmental activist.
The decision to water trees every day in May could be useful if another forecast of IMD turns into reality.
An IMD forecast on April 28 said eastern India, including most parts of Bihar, Jharkhand, Gangetic Bengal, eastern Uttar Pradesh and Odisha could experience two to six extra heat-wave days in May.
“We have taken a decision to water trees on the median dividers and on the green verge along pavements every day till May 31. Whether the duration needs to be extended will depend on the situation at the end of May,” said a KMC official.
The civic body has 12 tankers, each of 4,000-litre capacity, that are used to water trees. The tankers are also used to water large trees inside parks, such as Deshabandhu Park.
During the summer months, each tanker makes four to six trips in a day to water the trees. The requirement is lower during the monsoon and in winter.
“During winter each tanker does no more than four trips. Winter being a dry season, we need to water the trees regularly,” said the official.
KMC officials admitted that 12 tankers are not enough to water all the trees on Kolkata's roads. The civic body rarely waters large trees that form a canopy over roads, they said.
Some of the trees planted on the median dividers and in the roadside green verges are crape jasmine (togor), croton, dracaena and orange jasmine (kamini), said an official.