Thottappally Spillway

  

Thottappally Spillway is Kuttanad's drain-way out to the Arabian Sea. The Thottappally Spillway splits the Thottappally lake with the fresh water part to the east and saline Thottappally river mouth to the west merging with the Arabian Sea. Thottappally spillway is constructed to spill excess water coming over the Upper Kuttanad and Lower Kuttanad regions through Manimala River, Achancovil River and Pamba River. It is designed such that it could spill off 19,500 cubic meters of water per second, but after its construction it was found that it is able to spill 600 cubic meters of water per second. Reasons for this reduced flow rate are, strong sea breezes during rainy seasons resulting in a rise in sea level relative to the water level of Kuttanad, formation of sand bars on the western area of the spillway and the width of the leading canal is too narrow to carry this much water to the spillway

This project was designed as a permanent solution to the flood situation in Kuttanad. This programme was envisaged in such a way that flooded waters from Pamba, Manimalayar and Achankovil were diverted to the sea before it reached Vembanad lake. The construction of the Spillway ended by 1959.
In 1968, the government of India proposed that a bund (Dam) be made across the river so that seawater would not be allowed to come inside Kuttanad during summer, allowing farmers to cultivate an extra crop per year. The project was planned in three phases, the south side, the north side and another phase to join the two sections. The project was delayed and by the time the first two phases were complete the entire money allotted for the project ran out and left the final phase in limbo. The farmers who were expecting lots of financial benefits after the completion of the project decided to take matters into their own hands and one night in 1972, a large group of farmers filled the gap between the north and the south side with earth. To this day, the earth embankment between the two sections of the bund remains. With this, it was possible to close the regulator of shutters during December–June when the saline water enters, and then open it during monsoon. Once the Thanneermukkam bund and spillway became operational two crops were possible in Kuttanad.that are chambavu and karutha charu.
Even though the bund has improved the quality of life of the farmers, the bund is alleged to have caused severe environmental problems. The backwaters which were abundant with fish and part of the staple food of the people of the region require a small amount of salt water for its breeding. The bund has caused deterioration of fish varieties in the region and the fishermen opposed to the bund as of 2005. The bund has also disrupted the harmony of the sea with the backwaters and has caused problems not foreseen before the bund like the omniprescence of the water weeds. Earlier the salt water tends to cleanse the backwaters but this does not happen any more leading to the pollution of the backwaters

History

Spillway work forms part of the Kuttanad development scheme included in the first five year national plan. Spill way was inaugurated by Sri. Pattom Thanupillai on 5 December 1954.