Even though Kalimpong had moderate rainfall in the last few days, heavy rain was reported in Sikkim due which the Teesta river was swollen and swift.
What amazes me is that maintaining NH31A during the monsoons is a huge problem with sinking areas and landslides at numerous places yet there are plans to construct a broad gauge railway line all the way from Siliguri to Rangpo along this same route (see here)!
Perhaps we have forgotten that we did have the Kalimpong element of the the Darjeeling Himalayan Railway (DHR) functioning from Siliguri to Geille Khola (short of Kalimpong) along this route upto 1950. It was closed as being to dangerous to operate after the devastating landslides of that year.
Photo credits :- Chinlop Fudong Lepcha and Mukesh Sharma