Chalakudy · Dam floods · Kerala

Reservoir Operations Fail People in Chalakudy River Basin in Kerala in 2020

Guest Article by S P Ravi

Kerala continues to witness unusual monsoon rainfall patterns for the third straight year in 2020. Kerala had witnessed its worst flood in almost a century in 2018. The 2019 flood was probably second only to the 2018 floods over the last 50 years, with many places experiencing larger floods than that in 2018. While the state did not face huge floods this year, tragedy struck in the form of the Pettimudi landslide near Munnar in Idukki district. It buried alive 70 members of plantation labourer families, making it the worst ever landslide in Kerala in terms of human causality. Kerala has also witnessed its wettest monsoon in September in this millennium with a rainfall of 601 mm, surpassing the previous highest of 526 mm recorded in 2007. The S-W monsoon period is now over and the state received 2227 mm rainfall, which is 9 percent above long term average.

Continue reading “Reservoir Operations Fail People in Chalakudy River Basin in Kerala in 2020”
CWC - Central Water Commission · Dam Induced Flood Disaster · Kerala

ROLE OF DAMS IN 2018 KERALA FLOODS: Rejoinder of J Harsha to the response by Sudheer et al

Rejoinder Article by: J.Harsha

An article titled “Role of dams on the floods of August 2018 in Periyar River Basin” was published by Sudheer et al. (2019) in Current Science. A rebuttal was prepared and thanks to South Asia Network of Dams, Rivers and People (SANDRP), the same was published by SANDRP on 25th August 2020 (https://sandrp.in/2020/08/25/role-of-dams-in-kerala-floods-distortion-of-science/) for which Sudheer et al. (2019) has now furnished a response (https://sandrp.in/2020/09/19/response-of-sudheer-et-al-to-the-comments-by-mr-j-harsha-on-the-article-role-of-dams-on-the-floods-of-aug-2018-in-periyar-river-basin-kerala/).

In the rebuttal published by SANDRP, I had questioned the very basis of fitting HEC-HMS model for Periyar River Basin (PRB) by Sudheer et al. (2019), and also challenged the assumptions made by them, the methodology followed and the consequent voluminous inferences such as catchment response at Neeleshwaram (L2), virgin simulations, bank full discharges and particularly inferences that indicted nature for the flood calamity but exonerating the role of dams for the floods of Kerala in 2018. 

Continue reading “ROLE OF DAMS IN 2018 KERALA FLOODS: Rejoinder of J Harsha to the response by Sudheer et al”
Dam Induced Flood Disaster · Kerala

Response of Sudheer et al to the Comments by Mr. J. Harsha on the article, “Role of dams in the floods of Aug 2018 in Periyar River Basin, Kerala”

Sudheer, K P1,2,*, S. Murty Bhallamudi1,3, Balaji Narasimhan1,3, Jobin Thomas1, Bindhu, V M1, Vamsikrishna Vema1,4, Cicily Kurian1,
1Department of civil Engineering, Indian Institute of Technology Madras, Chennai – 600036,
2Department of Agricultural and Biological Engineering, Purdue University, West Lafayette, IN, USA.
3Indo German Centre for Sustainability, Indian Institute of Technology Madras, Chennai – 600036
*Corresponding Author: sudheer@iitm.ac.in

The authors of Sudheer et al. (2019) – hereinafter referred to as ‘authors’ – appreciate Mr. J. Harsha (hereinafter referred to as ‘commenter’) for his judgmental assessment (in his blog appeared on SANDRP website- “https://sandrp.in” on August 25, 2020, see: https://sandrp.in/2020/08/25/role-of-dams-in-kerala-floods-distortion-of-science/) of the authors’ work “Role of dams on the floods of August 2018 in Periyar River Basin, Kerala” (published in the Current Science in 2019: [DOI: 10.18520/cs/v116/i5/780-794]). As mentioned in Sudheer et al. (2019), the primary objective of the article was to examine whether the early release of the water stored in the reservoirs would have attenuated the flood peaks, and if so, what would have been the extent of the attenuation, in the context of debates and discussions in the social, political, as well as scientific domains based on non-sequitur speculations. Accordingly, the authors designed a scientific exercise using a widely used hydrological model (HEC-HMS) to understand the role of the dams in the Periyar River Basin (PRB) in the 2018 flooding situation.

Continue reading “Response of Sudheer et al to the Comments by Mr. J. Harsha on the article, “Role of dams in the floods of Aug 2018 in Periyar River Basin, Kerala””
Dam Induced Flood Disaster · Kerala

Role of dams in Kerala floods: Distortion of Science

Guest Article by: J.Harsha

Introduction: In August, 2018, devastated floods occurred in the southern Indian state of Kerala that led to widespread death and destruction to livelihoods. One of the worst affected basins was Periyar River Basin (PRB). While investigating the role of dams in the devastating floods, an article titled, “Role of dams on the floods of August 2018 in Periyar River Basin, Kerala” by Sudheer et al., (2019) was first published in the Current Science1 Journal brought out by Indian Academy of Sciences, Bengaluru, India on 10th March 2019. The journal article by Sudheer et al., (2019) adopts hydrological model to investigate the role of dams in the occurrence of floods in PRB and concludes that dams had less or little role in the occurrence of floods in comparison to the natural reasons. However, when the article was reviewed, it was found that the authors Sudheer et al., (2019) had made fallacious assumptions, errors in their methodology, adopted poor data quality and they have arrived at erroneous inferences and conclusions such as exonerating the role of dams in Kerala floods but indicting the nature as the cause of floods. This review article therefore, using RS & GIS (Remote Sensing and Geographical Information System) techniques challenges their inferences that is based on fallacious assumptions, accumulated errors in their methodology and the poor data quality fed into the hydrological model.

Continue reading “Role of dams in Kerala floods: Distortion of Science”
Dam floods · Kerala

Open Letter to Kerala Chief Secretary about Monsoon preparedness and disaster risk reduction

On May 7, 2020, a number of groups in Kerala wrote this letter to Kerala Chief Secretary on the important issue of Monsoon preparedness and Disaster Risk Reduction, with particular focus on Reservoir operations during Monsoon. This is an excellent initiative worth emulating by a lot of us in different states and at national level. Hence we are happy to Share this here with permission from the authors.

Sir,

The South-West monsoon is scheduled to arrive at Kerala by around June 1st. Early predictions on the monsoon by different agencies including the Indian Meteorological Department (IMD) suggest normal to above normal rainfall in India. The South-Western coast and adjoining regions are expected to get very good rainfall this year. It may be recalled that the state had to face extremely high-intensity rainfall incidents and consequent disasters in the last two years. Hence, the state needs to be well prepared to face any eventuality during the coming monsoon. The following concerns may be addressed and suggestions may be considered. Continue reading “Open Letter to Kerala Chief Secretary about Monsoon preparedness and disaster risk reduction”

Kerala · Rivers

Ozhukanam Puzhakal: UNTO HER WE SHALL RETURN…

Guest Blog by Dr Manju Vasudevan

Two artists are engrossed in some meaningful graffiti work at a public bus stand, on an otherwise laid back, colourless Sunday morning. A closer look and their strokes in fact seem to be urging the passerby to pay attention to rivers and water resources. There seems to be a message to all the drawings.  It is not often that one comes across a sight like this in small town Chalakudy in Kerala. The artists have teamed up with the Chalakudy River Protection Forum under the umbrella of a State-wide campaign titled ‘Ozhukanam Puzhakal’ or ‘The Rivers Must Flow’. Continue reading “Ozhukanam Puzhakal: UNTO HER WE SHALL RETURN…”

Kerala · Rivers

Ithikkara River in Kerala: Tampering with Nature – a recipe for negative NPV

Guest Blog by Jacob Chandy Varghese (jacob.c.varghese@gmail.com)

An Old Story: I read an account about Netherlands in the journal, Annals of Botany (2010)[i] . This story dates from the 11th century. Many centuries ago, the coastal plain of the Netherlands consisted of a dynamic landscape of meandering river channels, extensive floodplains and large complexes of fens and bogs. Sediment deposition and peat formation kept pace with the gradually rising sea level, so that the level of the land remained well above the water for most of the time. Since 11th century, inhabitants of the low-countries started to modify the hydrology of their surroundings to create protection from flooding for their dwellings and agricultural fields. They built dikes and started to manipulate the water level. Continue reading “Ithikkara River in Kerala: Tampering with Nature – a recipe for negative NPV”

Dam Induced Flood Disaster · Kerala

Role of dams in Kerala’s 2018 floods

ABSTRACT: Many independent observers have argued that dams have played a role in increasing the proportions of Kerala flood disaster during July-Aug 2018. This article shows that Kerala dams violated many basic norms and if operated prudently, could have helped. It shows how post dam floods are different than pre dam floods. It lists the steps that would help in future disasters involving dams. The lessons are useful for all large dams of India.

In theory, every dam can help moderate floods in the downstream areas, as long as and as much as the dam has space to store water. In fact, every action that helps to store, hold, recharge (to groundwater aquifer), delay flow of rainwater from the catchment to the river would help moderate flow and hence flood in the river. Our catchments are fast losing that capacity, with continued destruction of natural forests, wetlands, local water bodies and also soil’s capacity to hold water. Continue reading “Role of dams in Kerala’s 2018 floods”

Bhagirath Prayas Samman · Dams · Kerala · Western Ghats

Remembering Latha

It took some time to write. Latha chechi and me talked just 4 days before she passed away on Nov 16, 2017. As usual, it was about when we will meet next and go to Athirappilly Falls and travel to the river together. Her voice was light, it had a surreal gentleness. We agreed on everything, which was rare. After just a few minutes, Unni gently took the phone from her and told me she needed to sleep. It just didn’t feel right.

We first met virtually about 10 years back, discussing rivers and forests and then, through her initiative, came together to organize the first civil society workshop on Environmental Flows in January 2009 with SANDRP.  Since then, Latha Chechi has been a bubbling, enthusiastic and wise constant. We worked on several submissions together, discussed strategies and ideas, eating each other’s heads about what worked and what can work and always, I was always taken aback by her unmatched way of linking issues.

She told me, “You need one particular river. Work on all the rivers of world, but have that one river to go back to.” Continue reading “Remembering Latha”