Sikkim bracing for a ‘fast & furious’ monsoon fury

BIJOY GURUNG

GANGTOK,: June is anticipated to be a worrisome month for Sikkim as heavy rainfall events are increasing every monsoon in the hilly State which is still recovering from the destructive flash flood of October 2023.

Above-normal monsoon is forecasted this monsoon across India including Sikkim due to the weather phenomenon called ‘La Nina’, arising from Eastern Pacific Ocean.

Sikkim is habituated to intense monsoon rains but increasing heavy rainfall events may worsen the already battered Teesta riverine terrain and major roads including NH 10 that run alongside it, experts fear.

In other words, the frequency of intense rains for short durations is increasing which results in landslides and swelling of river levels making the fragile terrain more prone to landslides and washouts.

Indian Meteorological Department (IMD), Gangtok shares with SIKKIM EXPRESS that though the general monsoon forecast for Sikkim is also above-normal, there has been a jump of heavy rainfall events with the corresponding decrease in rainy days over the past few years in the State.

“Overall the total annual rainfall is more or less the same here for the past few years…it is not increasing or decreasing much. However, the number of rainy days (the days when it is raining) is decreasing but the total rainfall is almost the same. It can be interpreted as that when it rains, the rains are intense and fast, and the heavy rainfall events are also increasing,” explained IMD Gangtok head Dr. GN Raha.

This means that extreme weather events are increasing due to climate change, and so we are having intense rains for a short duration, added Dr. Raha.

Monsoon in Sikkim usually commences from first week of June and extends up to second week of October. The State gets about 60%-65% of its annual rainfall during this period and some of it would come as heavy rainfall events this season also.

June is expected to bring heavy rains in Sikkim and adjoining North Bengal.

The concern is, of course, on how the above-normal monsoon rains would affect the Teesta river belt post last year’s flash flood. Besides moderate settlements at certain stretches, the greater worry is about the connectivity disruption as almost all the major roads (Singtam to North Sikkim) and NH 10 run parallel to the river’s course. The damaged roads have not been permanently restored while bailey bridges have been installed at places where the bridges have been washed out like Sangakhlang which connects Dzongu with rest of Sikkim.

Experts have already pointed out that the river’s morphology has undergone major changes after the last October flash flood. Heavy siltation has also increased the river’s level that could see an abrupt jump this time, depending on the monsoon fury in the upper reaches.

The IMD Gangtok had presented its observations and reports to the Sikkim government during the May 1 State-level pre-monsoon preparedness meeting held at Tashiling Secretariat.

Recognizing the potential threats, the authorities are making arrangements to ensure that timely alerts of water level increasing are communicated to the riverine settlements and field-level authorities. The SSDMA is working closely with the Central Water Commission (CWC) and State Water Resources department on this. Water level monitoring systems are installed at the major bridges.

Monsoon in India lasts from June to September and this time, ‘La Nina’ is expected to cause above-normal rainfall across the country.

In India, an El Nino is associated with a harsher summer and weaker monsoon. La Nina, on the other hand, is associated with a strong monsoon and above average rains and colder winters in the subcontinent.