Floods · Hydropower · Uttarakhand

Uttarakhand Floods: Truth about THDC and Central Water Commission’s Claims about Tehri

June 28, 2013

The claim of THDC, CWC and Uttarakhand Chief Minister that in absence of Tehri dam, Rishikesh and Haridwar would have been washed away is completely baseless and unfounded, nothing but a hype. Facts show that if Tehri Dam id not exist, the water level in downstream towns may have risen on June 16-17, before the levels actually rose on June 18 (as per CWC, peak level in Rishikesh was 340.8 m and in Haridwar at 295.1 m, both on June 18), but are likely to be lower than the levels of June 18 since peak flow in Alaknanda (around 11000 cumecs) was lower than that in Bhagirathi (6900 cumecs). THDC and CWC should refrain from making such claims as they are more like adding salt to the wounds that the people of the state are now experiencing and where dams and hydro projects have played a big role.

From all accounts, it is clear that peak flood in Bhagirathi River on which Tehri dam is situated, occurred on June 16 and the peak flood in Alaknanda occurred on June 17 and not at the same time. So it is not rational to add the two peaks happening at different points of time to claim that Tehri saved downstream areas. If Tehri was not there, there could have been floods in downstream a day earlier, but that does not mean peak level would have been much higher than what was the case with Tehri Dam.

From the records available on the websites of Central Water Commission (http://cwc.gov.in/Reservoir_level.htm) and Central Electricity Authority (http://cea.nic.in/daily_hydro.html), it is clear that water level in Tehri reservoir rose from 749 m on June 15 to 776.8 m on June 18 (water levels for June 16 and 17 are not available for some strange reason), this translated to increase in water storage by 652 Million Cubic meters (MCM). THDC claims that they experienced peak inflow of 244 000 cusecs and moderated that to an outflow of 14000 cusecs. To achieve this moderation for a day would take storage capacity of around 563 MCM, so it is plausible that they achieved this moderation on June 16, when Bhagirathi was experiencing peak flow.

However, as we noted earlier, the peak flow in Alaknanda happened on June 17. THDC should make public hourly figures of flow in Bhagirathi and Alaknanda on June 15-19, outflow from Tehri on each of those hours, level of Ganga at Devprayag, Haridwar and Rishikesh, so that everyone can assess the reality of their claim. Such information should in fact be in public domain in routine way.

It cannot be forgotten that:

  • Areas downstream of Tehri dam faced avoidable and unprecedented flood disaster in September 2010 (for details see page 20 of Aug Sept 2010 issue of Dams, Rivers & People: https://sandrp.in/drp/DRP_Aug_Sept_2010.pdf). If the dam operation is not done properly, we may be in for a repeat later this season.
  • It should also be recalled that Tehri is a ticking time bomb in the context of large earthquake that is imminent in the state as seismologists are telling us.( including eminent seismologists like Dr. Vinod Gaur. For more details: Earthquakes and Large Dams in Himalayas)
  • In fact, Tehri Dam sits on an active fault and seismincity near Tehri area is also related to loading and unloading ot the resrvoir (http://www.currentscience.ac.in/Volumes/103/11/1343.pdf)
  • Tehri dam has also been cause of large number of landslides along periphery of the reservoir. In fact, when Tehri dam was about to be complete, 28 workers had died when working in the water diversion tunnel. (http://www.infochangeindia.org/disasters/news-scan/29-killed-in-tehri-canal-collapse-early-warnings.html)
Landslides and debris flowing into Tehri Reservoir. 2012. Matu Jan Sangathan
Landslides and debris flowing into Tehri Reservoir. 2012. Matu Jan Sangathan
  • People affected by the Tehri dam have still not been rehabilitated, the dam has also not been delivering the peaking power it could, as noted by Central Electricity Regulatory Authority. The dam is also silting up much faster than envisaged, reducing its water holding and power generation capacity.

In fact, CWC has failed in its flood forecasting as we made it clear earlier. Both CWC and THDC need to put their house in order rather making unfounded claims.

Himanshu Thakkar (ht.sandrp@gmail.com, 09968242798)

South Asia Network on Dams, Rivers & People  (https://sandrp.in/)

For SANDRP blogs on Uttarakhand flood disaster, see:

1. https://sandrp.wordpress.com/2013/06/21/uttarakhand-deluge-how-human-actions-and-neglect-converted-a-natural-phenomenon-into-a-massive-disaster/

2. https://sandrp.wordpress.com/2013/06/23/uttarakhand-floods-disaster-lessons-for-himalayan-states/

3. https://sandrp.wordpress.com/2013/06/25/uttarakhand-and-climate-change-how-long-can-we-ignore-this-in-himalayas/

4. https://sandrp.wordpress.com/2013/06/25/central-water-commissions-flood-forecasting-pathetic-performance-in-uttarkhand-disaster/