VIJAYAWADA: Central Water Commission (CWC) may take up afresh a study on impact of Polavaram irrigation project backwaters at a discharge of 36 lakh cusecs.
The possibility emerged on Friday when centre organised a high-level meeting in New Delhi with representatives of Central Water Commission, Polavaram Project Authority and states concerned, including Andhra Pradesh, Telangana, Odisha and Chhattisgarh.
In particular, Telangana, Odisha and Chhattisgarh have complained that several of their areas are getting submerged owing to impact of Polavaram’s backwaters. Responding to their concerns at the meeting, CWC asked the three states to submit their technical details by October 19. The commission will then peruse them and take a decision on either initiating corrective measures to reduce the impact of backwaters or take up a fresh study altogether on the project’s backwaters.
Godavari River witnessed highest floods with a discharge of 36 lakh cusecs of water from Sir Arthur Cotton Barrage at Dowleswaram in 1986. Since then, the river has not witnessed such huge floods. Even in July last, Godavari witnessed a discharge of 24.88 lakh cusecs at Bhadrachalam and nearly 22 lakh cusecs at Polavaram.
Water resources authorities maintain that if one in 100 floods of Godavari is taken into consideration, the river has witnessed the highest floods of 28.74 lakh cusecs at Dowleswaram barrage. In case it is one in 50 floods, the river discharged 25.15 lakh cusecs. However, if one in 500 floods are taken, the river witnessed 36 lakh cusecs.
The spillway of Polavaram has been designed to withstand 50 lakh cusecs of water discharge. There is also a chance that the discharge may even touch 58 lakh cusecs. Considering this possibility, AP’s neighbouring states have demanded a study about the impact of backwaters at such levels.
AP has been maintaining that designs of Polavaram have been approved by all statutory agencies, including Dam Design Review Committee, CWC and PPA, before it got the go ahead for construction of the project. The state has contended that it is implementing the project accordingly.
However, Telangana complained that parts of Bhadrachalam had got submerged during the recent floods in Godavari due to afflux under the influence of backwaters of Polavaram project. AP authorities maintained that there is no Polavaram dam in place as yet. Hence, it ruled out that Polavaram’s backwaters had impacted Bhadrachalam.
AP pointed out that Godavari had this year witnessed floods wherein water level in the river had risen rapidly, which is a natural phenomenon.
AP water resources engineer-in-chief C. Narayana Reddy said, “Flooding in parts of Bhadrachalam had been due to streams carrying huge quantities of water following heavy rains. This water did not get fully emptied into the river, as the water level in the river itself had been high due to floods. However, we have agreed for a joint survey with Telangana. We will take up any corrective measures required to avoid submergence in Telangana.”
There is also the issue of flood gauging equipment developing flaws at several points all the way from Bhadrachalam to Polavaram. The quantum of water discharged at Bhadrachalam is supposed to get reflected at Polavaram after some time. But this did not happen in reality. When Bhadrachalam recorded discharge at 24.88 lakh cusecs, Polavaram recorded nearly 22 lakh cusecs, while Dowleswaram recorded the same quantum recorded at Bhadrachalam. AP intends to take up rectification of lapses in flood gauging equipment set up by the CWC.
At the meeting, AP expressed its willingness to compensate both Odisha and Chhattisgarh for the loss caused due to inundation in some of their areas or strengthen their flood banks, provided those states conduct an environmental impact assessment and public hearing.
Polavaram project chief engineer B. Sudhakar Babu maintained: “We have been following directions of all statutory agencies scrupulously while executing the Polavaram project. Accordingly, CWC has asked neighbouring states to substantiate their claims. The issue of submergence could be revisited under those circumstances.”
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