Coronation Bridge (Teesta)
The Coronation Bridge, also known as the Sevoke Bridge, in Darjeeling district of West Bengal, India, spans across the Teesta River, connecting the districts of Darjeeling and Jalpaiguri. National Highway 31 runs across it.
It was named to commemorate the coronation of King George VI and Queen Elizabeth in 1937 and was completed in 1941 at a cost of Rs 4 lakhs. The foundation stone of the bridge was laid by John Anderson, the then Governor of Bengal in 1937.
Locals call the bridge Baghpool, meaning tiger bridge, because of the two lion statues (bagh actually means tiger) at one entrance of the bridge. The bridge is also called Lohapul (Iron Bridge) as it is made of steel.
John Chambers, the last British executive Engineer of the Darjeeling Division Public Works Department (PWD), carried out the design, drawing and planning of the bridge. Messrs J. C. Gammon, from Bombay, was the contractor. The bridge was built on the Reinforced Concrete system.
Since it was not possible to obtain support from the Teesta river bed due to the depth and current of water, the entire bridge was supported by a fixed arch, which had its two ends fixed on rock layers on either side of the river. “Given its architectural and historical value, the bridge should be declared a heritage site. Traffic should be regulated and maintenance work carried out properly,” Bagchi said.
There are four spans of 150 feet with a central span of 250 feet. The wells as well as the piers were built in cement concrete. The bed of the river was full of boulders up to four feet diameter, and therefore, the wells had to be sunk by the pneumatic process.
The members for the 250 feet girder were brought to the site of the work by the end of February 1949. As the girder could not be end-launched, it had to be assembled on an island in the bed of the river slewed to come alongside the span and raised on top of the piers before the floods which were expected any time after March. The 150 feet girders were all erected on the right bank and end-launched one by one from this bank with an assisting 150 feet span temporarily connected at the back of the span to be launched. All girder erections were completed on 25th June 1949 when the river was in high flood.
A guide bund with concrete-block apron and boulder-pitched slope was built on the left bank to train the river through the bridge. The bridge was opened for goods traffic on 9th December 1949.
The Tista which was estimated to take a discharge of two and a half lakh cusecs, brought in, as a result of exceptionally heavy rainfall, a discharge of about six lakh cusecs and, in the early hours of 12th June 1950, the flood over-topped the left guide bund and caused a breach of 750 feet in the embankment at the back of the east abutment and 80 feet at the back on the west. Dislocation to this vital line of communication could not be allowed to remain indefinitely. Incessant day and night work by the staff of the Assam Rail Link through heavy monsoon and floods enabled restoration of the line of communication on 2nd August 1950. The pile bridge in the east approach was built on a division 30 feet away from the centre-firm of the permanent bridge so that, in case it was decided to extend the permanent bridge, necessary working room would be available.
The design of the waterway for this bridge was thoroughly investigated by the Central Water Power, Irrigation and Navigation Commission, and on their recommendations the extension of the bridge by adding 3 x 150 feet spans on the east was ordered. The bridge was finally completed after constructing these three additional spans of 150 feet on the east end, i.e., with spans of 2 x 150 feet, 1 x 250 feet and 5 x 150 feet spans, and a guide bond was provided on the east bank for guiding the water through the bridge. The bridge was reopened for passenger traffic on 24th February 1951.