Polavaram Spillway and gates pose a major challenge
The spillway and the gates, main components of the Polavaram Project, are the big tasks before the Irrigation department and the Transtroy company, which have taken up the completion of the first phase of the major irrigation project before the end of 2018. The project site wears a busy look with earth movers in hundreds moving from one end to the other on one hand and huge cranes engaged in concrete work on the other. After Chief Minister N. Chandrababu Naidu expressed displeasure over the pace of the earth work, Transtroy tried to speed it up in the last three days, but the sudden rain for a day and the cloudy atmosphere the next day threw a spanner in the work.
“Our target is two lakh cubic metres per day, but the company has been doing only 1.5 to 1.6 lakh cubic metres per day for the last one week. The rain hampered the work in the last three days,” said V.S. Ramesh Babu, Chief Engineer of the project. However, the diaphragm wall construction is going on at a fast pace at 38 running metres per day against targeted 29 running metres. The work of making gates is going as per schedule and with the company making two gates a week. “Geological mapping is being done for the project in a systematic way. We are getting the latest maps as per schedule,” said Mr. Ramesh Babu.
Asked about the concrete work, the Chief Engineer said they were not doing it during day time as the temperature was crossing 40 degrees. The dam concrete mixture requires 14 to 18 degrees. He said chilling technology was being used for making concrete and they were doing it only during night. “Yes, the half-a-day work is also delaying concrete mixing and it will speed up during the monsoon. However, during the monsoon other works will be disturbed,” he admitted. Concrete mixing would be done at 1,300 to 1,500 cubic metres a day, according to the engineers.
Work would be taken up in the hilly portions of the project during monsoon. “We have to complete the major portion of the work before summer and completion of the first phase by 2018 will be possible only if we complete spillway and gates by next January. The copper dam will be constructed immediately after the completion of the spillway and gates and then water will be released through gravity,” said Mr. Ramesh Babu.
Source : http://www.thehindu.com