Farm labourers transplant rice at Bullapur village in Tungabhadra command area of ​​Raichur district on Saturday. | Photo credit: Santosh Sagar

Thanks to steady inflow, the Tungabhadra reservoir at Hosapete in Vijayanagara district has received around 14 cubic feet of water since the broken dam crest gate was repaired a week ago. The steadily rising water level in the reservoir has given new hope to farmers in the district who were battling water shortage for their fields after one of the dam gates was washed away and huge quantities of water were lost.

According to Tungabhadra Board data, the reservoir level was 1,627.54 feet at 7:30 am on Saturday with a storage capacity of 85,113 tmcft against a full reservoir level (FRL) of 1,633 feet with a total capacity of 105,788 tmcft.

At around 10:50 pm on August 10, Gate No. 19 was washed away when its chain link broke. As a result, water began pouring out of the reservoir, which was filled to the brim, at a rate of 36,000 cubic feet per second. To relieve the pressure on the broken gate, authorities immediately raised all the other 32 gates to a level that would allow the water to be released into the river.

Experts at work

Teams of experts arriving from Hyderabad, Bengaluru and Chennai the next day were of the opinion that the dam needed to be half drained to start repair work. Accordingly, the discharge rate of the spillway was further increased to 1.4 lakh cubic feet per second to release the water as soon as possible.

The incident dashed the hopes of farmers in Tungabhadra command area who had prepared their land and were waiting for water to start rice transplanting.

However, a team of experts led by hydraulic engineer N. Kannayya Naidu continued to try to repair a dam gate as a temporary measure to conserve water in the reservoir. After a week of trial and error, they finally managed to fix the dam gate (a temporary gate made of five rectangular boards 4 feet high and 60 feet wide placed one on top of the other) in place of the damaged gate. Soon, all the gates could be closed.

However, a week of increased discharge from the spillway to facilitate repair work had resulted in a loss of about 35 tmcft of water in the reservoir. However, the persistent rainfall, albeit mild, in the vast catchment area of ​​the river upstream ensured a constant inflow into the dam, so that after the repair of the dam gate, the reservoir received about 14 tmcft of water in just seven days.

For a harvest

“This year, there will be no shortage of water for one crop. The rice transplantation at the upper stretch of the canal has already been completed. The farmers at the end of the canal have now started transplantation. The crop needs water till November and the available water in the reservoir will be more than sufficient. However, it would not be enough for a second crop. We hope that the rains continue in the catchment area and the reservoir will be full again so that we get water for the second crop as well,” said Chamarasa Malipatil, honorary president of the Karnataka Rajya Raitha Sangha.