22 July 2020

Director General,

Central Environmental Authority,

104, Denzil Kobbekaduwa Mawatha,


Dear Sir,


Centre for Environmental Justice is a public interest environmental organization based in Sri Lanka established in 2004. We herewith send our comments to the above EIA under the request for public comments as per the National Environment Act, No 47 of 1980.

  • To meet rising electricity demand, growing at around 6 per cent annually and expected to reach almost 17 TWh by 2020, the CEB is aiming to increase overall power capacity from 4 GW currently to almost 7 GW by 2025. Currently Sri Lanka has installed hydropower capacity 1,720 MW (2017) Hydropower generation 2,785 GWh (2017).
  • Seethawaka Ganga Hydropower Project (SGHP)(24 MW) was one of the potential projects on the horizon along with Thalpitigala (15 MW), Moragolla (30 MW), Gin Ganga (20 MW). Project components include 112 m long and about 32 m high Power station, Surge tank, Headrace Tunnel, Penstock, Tailrace channel, Switch yard, and a Transmission line estimated at USD 79 Million. This is a run of river type project with an impounding area 40 ha and reservoir capacity of 3.51 MCM.
  • Seethawaka River project was identified in the Master Plan produced by CEB in 1989 as Sita014. The project was on the Seethawaka Ganga which is an upper tributary of the Kelani River and was initially identified as a 30MW capacity producing 123 GWh per year. However, due to Social and Environmental considerations, the project is scaled down to a lower capacity 2x 12W with 54 GWh hydro power plant. (CEB).  Yet the Max. Height of main dam from foundation will be  36 m and the Length of main dam will be  112 m.
  • We are concern about this project since the project is located in a high biodiversity area, landslide prawn mountains. The previous project was rejected due to the high negative impacts.
  • The project EIA shows the reasons why it should be considered as a biological hot spot. We are highly concern about the calculation of the environmental flow and inadequacy of the eco-flow suggested by the EIA. Please find more detailed comments below.


  • According to the floral and fauna survey conducted in the area following findings  were identified.
  • Seven (7) aquatic species in five (5) families including no endemics and threatened species, Eight (8) semi aquatic species in four (4) families including four (4) endemic, with two (2) threatened in the expected inundation area and downstream.
  • Twenty seven (27) freshwater fish species in 12 families have been recorded from the effecting river stretch with 13 are endemics and 8 eight in the endangered (Sri Lanka Day’s Killifish, Sri Lanka Giant Snakehead, Sri Lanka Cuming’s Barb, Sri Lanka Black Ruby Barb, Sri Lanka Redfined Barb, Sri Lanka Kamalica’s Barb, Sri Lanka Black-Lined Barb, Sri Lanka Tiger Loach)
  • Also, One hundred and ninety-four (194) plant species in seventy-two (72) families have been recorded in of the dam upstream area which will be inundated. This includes fourteen (14) endemic species and fourteen (14) threatened species. One hundred and twenty five (125) faunal species in fifty-eight (58) families have been recorded including twenty-two (22) endemics and eighteen (18) threatened species.
  • Bio diversity in the downstream area up to 1.9 km, especially the riparian zone is important as the area is directly affected due to the shortage of water. One hundred and twenty three (123) floral species in fifty-five (55) families have been recorded in the riparian zone of the downstream area during the survey. This includes twelve (12) endemic species and fifteen (15) threatened species including ten (10) Vulnerable, two (02) Endangered, and three (03) Critically Endangered species. Cryptocoryne alba, Calophyllum cunefolium( Keena), Cyathea hookeri(Heen Ginihota)  are the three (03) Critically Endangered species identified.
  • Ninety one (91) faunal species in fifty-one (51) families have been recorded in the riparian zone of the downstream area, including eighteen (18) endemics The endemic species includes six (06) endangered species including four (04) globally endangered species and seven (07) vulnerable species (Table 3.35). Pseudophilautus popularis* (Common shrub frog) and Adenomus kelaartii* (Kelaart’s dwarf toad) are the two (02) globally endangered frog species found in the downstream area while Macaca sinica (Sri Lanka toque macaque) and Loris tardigradus* (Sri Lanka red slender Loris) are the two (02) globally endangered mammal species recorded in the riparian zone of the downstream area.
  • According to the survey following observations has been made in Spoil areas and built up areas. Eighty six (86) floral species in thirty three (33) families with five (05) endemics and three (03) threatened species including two (02) Vulnerable, and one (01) Endangered species and One hundred and four (104) faunal species in fifty-two (52) families have been recorded in the sites selected for spoil areas and built up areas. This includes nineteen (19) endemics with eight (08) threatened species. Globally threatened Adenomus kelaartii (Kelaart’s dwarf toad) was found in the riparian site selected for construction waste dumping. Further, five species of freshwater fish were recorded from the stream bordering on of the spoil sites and built up areas (i.e. playground). Of the five species of fish recorded two are endemic.


  • Environmental flow calculation of the project has been calculated using the multiple criteria based scoring system for the determination of ecological demand of a river/ stream introduced by Central Environmental Authority. However data has been inserted incorrectly. For example Number of Critical species present has been inserted as 1, which is incorrect. Also, Number of Threatened aquatic or aquatic associated species present been inserted as 6. However fish species alone consist of 08 eight in the endangered.
  • (Sri Lanka Day’s Killifish, Sri Lanka Giant Snakehead, Sri Lanka Cuming’s Barb, Sri Lanka Black Ruby Barb, Sri Lanka Redfined Barb, Sri Lanka Kamalica’s Barb, Sri Lanka Black-Lined Barb, Sri Lanka Tiger Loach). Number of Endemic aquatic or aquatic associated species present that are not listed as threatened species is inserted as 2. However fish species alone consists 05 five in the endemic and not threatened category. Therefore, 3.78 cumecs as the calculated e flow should be a higher figure. Among all, justifying 1 cumecs e flow as required e flow on the basis that the river survived for 28 days in February 1989 and 26 days in March 1989 with an average discharge of 0.3 cumecs and 18 days in April 1989 with average discharge of 0.2 cumecs is not very scientific.
  • According to the figure 3.25 the above recommended e flow will be available to almost 5 months of the year. Therefore we think E Flow calculation is not in line with the E-Flow guidebook published by the Central Environmental Authority.


  • Storage capacity of hydropower reservoirs is lost due to sediment deposition. The problem is severe in projects located on rivers with high sediment concentration during the flood season. Removing the sediment deposition hydraulically by drawdown flushing is one of the most effective methods for restoring the storage capacity. EIA report mention that Silt removal will be through the bottom outlet of 3 m x 3.5 m size during high rainfall events, and if required through mechanical dredging during dry seasons. However it does not provide any details on silt generation rates of the river/ along the reservoir profile. Mechanical dredging involves cost and it should be included in the cost benefit analysis.


  • Further we would like to comment on section 9.2 of the EIA report on ecological aspects. An independent monitoring to estimate the abundance, density and distribution of two Anguilla species in downstream section of the river and impacts in comparison to an established initial baseline data set in order to mitigate the adverse impacts of fish migration. In addition to the downstream area, as a control group, an ecologically similar tributary of Kelani Ganga with known presence of Anguilla species (such as Gurugoda oya) is proposed to be sampled in equal measure. We would like to see the above study reports made available to the public.
  • EIA report highlight the absence of Strategic Environmental Assessment conducted in the area to further assess the environmental conditions or overall impacts of the river system and surrounding habitats in the area, except the studies carried out for the SGHP. Therefore we believe decisions must be made based on all the available data in hand and otherwise it would be too late to conserve a rich eco system with unique aquatic fauna.


  • Upstream of this project has at least 13 mini hydro projects and one rafting location. There is no cumulative impacts analysis in this EIA. Therefore one cannot understand the collective impacts to the biological diversity, hydrology and social impacts etc.


Finally, we request you to arrange an ORAL PUBLIC HEARING for us to make a submission on these matters, 


Absence on a Strategic Environmental Assessment (SEIA), no study on the accumulated impacts, leads to inadequacy of baseline information to make hard to come up with a final opinion. We hope you remember in our court case SC FR 57/2017 we have come to an agreement  on the importance of the SEIA however it had an unfortunate ending due to the U turn taken by the Sustainable Energy Authority due to political reasons and the pressure by the mini-hydro developers. It would have provide adequate baseline and consensus on the remaining capacity of the Sithawaka Ganga for mini-hydro power and some of the doubts would not have aroused. Absence of such a study we remain doubtful about the carrying capacity of the Sithawaka Ganga and the true impacts.      

However, We strictly urge you to consider above matters and the proposed environment management plan to make sure no serious negative environmental impacts and maintain best safety practices during the project implementation.

Thank you

Yours sincerely

Hemantha Withanage

Centre for Environmental Justice

Indika Rajapaksha

Environmental Officer

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